Sugarcane Issue - LSU AgCenter/media/system/4/a/8/3/4a83c3029ef5… · Research Station and St. Gabriel Research Station, St. Gabriel, La. S OVERVIEW Photo by John Wozniak Photo by

Louisiana Agriculture, Fall 2001 1

Fall 2001Vol. 44, No. 4

Sugarcane Issue

2 Louisiana Agriculture, Fall 2001

EDITORIAL BOARD:David J. Boethel (Chairman)Linda Foster BenedictPat BollichJames ChambersBarbara Groves CornsCaye DrapchoJane HoneycuttT. Eugene ReaganDavid Sanson

Published quarterly by the LouisianaAgricultural Experiment Station,Louisiana State University AgriculturalCenter, Baton Rouge, Louisiana.Subscriptions are free. Send requestsand any comments or questions to:

Linda Foster Benedict, EditorLouisiana AgricultureP.O. Box 25100Baton Rouge, LA 70894-5100

phone (225) 578-2263fax (225) [email protected].

www.lsuagcenter.com

EDITOR: Linda Foster Benedict

DESIGNER: Barbara Groves Corns

PHOTO EDITOR: John Wozniak

CONTRIBUTOR: Jane Honeycutt

The mention of a pesticide or use of a tradename for any product is intended only as areport of research and does not constitute anendorsement or recommendation by the Loui-siana Agricultural Experiment Station, nor doesit imply that a mentioned product is superior toother products of a similar nature not men-tioned. Uses of pesticides discussed here havenot necessarily been approved by governmentalregulatory agencies. Information on approveduses normally appears on the manufacturer’slabel.

Material herein may be used by the press, radioand other media provided the meaning is notchanged. Please give credit to the author and tothe publication for any material used.

Louisiana State University AgriculturalCenter, William B. Richardson, Chancellor

Louisiana Agricultural ExperimentStation, William H. Brown, Director

The Louisiana Agricultural Experiment Stationprovides equal opportunitiesin programs and employment.

Photo by Mark Claesgens

Each year, Cameco of Thibodeaux donates a used, refurbished combine harvester to beused in the research effort at the LSU AgCenter’s Sugar Research Station. This photowas taken at the 2001 annual sugarcane field day. Two of the presenters were BenLegendre, sugarcane specialist, left, and Mark Tassin, Iberville Parish county agent.

ON THE COVER: Kenneth Gravois is resident director of the Sugar ResearchStation at St. Gabriel, La., where the sugarcane breeding research is conducted.

Partners in ResearchThe comprehensive research program in sugarcane at the LSU AgCenter

results from cooperative relationships with many organizations and institutions.Two prominent cooperators in Louisiana are the American Sugar Cane League,headquartered in Thibodaux, and the U.S. Department of Agriculture’s Agricul-tural Research Service’s Sugarcane Research Unit in Houma. A stellar example ofthe power of this three-way partnership is the development of LCP 85-384.

“The LSU AgCenter helps our farmers be better growers and businesspeople,” said Charles J. Melancon, president and general manager of the AmericanSugar Cane League. “Agriculture in any state cannot do without the land-grantcolleges that support the industry. We work together for our mutual benefit.”

The American Sugar Cane League’s mission is to support research andlegislation for the betterment of the domestic sugar industry. The league includesnearly 100 percent participation among Louisiana’s sugarcane growers andprocessors.

The mission of the USDA’s Sugarcane Research Unit is to conduct basic andapplied research to increase sugarcane production efficiency while minimizing theimpact of the crop’s culture on the environment and other ecosystems in the highrainfall, mineral soil and subtropical climate of the lower Mississippi Delta withgeneral applicability to other mainland sugarcane-producing areas.

“Working together, the research programs of the LSU AgCenter and theUSDA, with the help and support of the American Sugar Cane League, providesthe Louisiana sugarcane industry with the varieties and management strategiesnecessary to insure the industry’s profitability despite frequent threats fromweather-related disasters and attacks from disease, insect and weed pests,” saidEdward P. Richard Jr., research leader at the Houma Sugarcane Research Unit. “Asa result of these research efforts, which also extend into the processing aspects,sugarcane continues to be a major contributor to the state’s economy.” Linda Foster Benedict


Volume 44, Number 4, Fall 2001

Page 11

Page 21

SCIENCE NOTES

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CONTENTS

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4 Louisiana’s Sugarcane IndustryKenneth Gravois

6 Sugarcane: An Important Industry Facing Many ChallengesFreddie A. Martin and Jeffrey W. Hoy

7 Planting Sugarcane: Whole Stalks Versus BilletsJeffrey W. Hoy

10 Controlling DiseaseJeffrey W. Hoy

12 Weed Control: Essential to Sugarcane ProductionJames L. Griffin, Blaine J. Viator, Patrick A. Clay, Jeffrey M. Ellis, Donnie K. Miller, Stacey A. Bruff,Andrew J. Lanie and Reed J. Lencse

16 Integrated Pest Management in SugarcaneT. Eugene “Gene” Reagan

19 New Sugarcane Varieties Pay Big DividendsKenneth Gravois and Keith Bischoff

24 Economic Analyses Help Sugarcane Growers’ Bottom LineMichael E. Salassi

26 Audubon Sugar Institute Addressing Processing Research NeedsPeter Rein

29 Fertility Research Helps Optimize Sugarcane ProfitsWilliam Hallmark, Greg Williams, Lester Brown and Gert Hawkins

32 Sugarcane Producers and Best Management Practices: Attitudesand InfluencesSteven A. Henning and Hugo Cardona

36 Prescribed Burns Help the Sugarcane Industry and ReduceSmoke and Ash ProblemsBenjamin L. Legendre

15 Fallow Period Cropping to Soybeans Can Provide BenefitsHoward P. “Sonny” Viator and James L. Griffin

17 Mexican Rice Borer ThreatT. Eugene “Gene” Reagan and M.O. Way

18 Value of Nontarget OrganismsT. Eugene “Gene” Reagan

28 Audubon Sugar Institute: Poised to Continue Its Proud TraditionPeter Rein

28 Sugar Product May Substitute for Antibiotic in Animal FeedDonal Day

34 Herbicide Losses in Surface RunoffRichard Bengtson and Magdi Selim

38 Resistance of Louisiana Sugarcane to Deteriorationfrom Freezing TemperaturesBenjamin L. Legendre

39 Scientists Use Precision Farming to Monitor Sugarcane YieldsCaryn E. Benjamin, Michael P. Mailander and Randy R. Price



ugarcane has been an integral partof the South Louisiana economy andculture for more than 200 years. Whenthe Jesuit priests first brought sugarcaneto Louisiana in 1751, little did theyknow that they were laying the founda-tion for an industry that now contributes$2 billion to the Louisiana economy. Inthe last century, research advances inboth production and processing havekept Louisiana’s sugar industry com-petitive. In these recent times ofstagnant and decreasing sugar prices,increased production efficiencies andnew processing technologies havehelped the Louisiana sugar industryremain profitable. The focus of LSUAgCenter sugarcane research is to helpmaintain a competitive and viable sugarindustry in Louisiana.

Sugarcane is a tropical crop tryingto survive in Louisiana’s temperateclimate. The ability to grow sugarcanein Louisiana and increase sugar yields tolevels attained in the tropics has largelybeen the result of sugarcane breedingefforts. These efforts began in Louisianain the early 1920s. The LSU AgCenter’s

most recent variety release, LCP 85-384in 1993, was a cooperative effortinvolving the U.S. Department ofAgriculture’s Agricultural ResearchService in Houma, La., and the Ameri-can Sugar Cane League. LCP 85-384 has revolutionized Louisiana’ssugar industry not only with yieldsup to 25 percent higher than othervarieties but also with the ability toprovide additional annual cuttingsof stalks, termed stubble crops(because the new crop of stalksdevelops from the stubble remain-ing after harvest). The typicalrotation for Louisiana sugarcanehas been to harvest a plantcanecrop and two stubble crops from asingle planting of sugarcane. WithLCP 85-384, farmers can obtainthree to four stubble crops with asingle planting. Because of theheavy tonnage, the new variety hasa tendency to fall down or lodge.Because of this, a new combineharvesting system was introducedin Louisiana in the mid 1990s.Combine harvesting systems arebetter suited to varieties such asLCP 85-384 and have improvedharvest efficiency in Louisiana.

In 2000, LCP 85-384 occupied71 percent of the state’s acreage.Indications for the 2001 crop are

for this variety to account for more than80 percent of the state’s acreage. Novariety in the history of the Louisianasugar industry has had such an impact.

Kenneth Gravois, Resident Director, SugarResearch Station and St. Gabriel Research Station,St. Gabriel, La.

S

OVERVIEW

Phot

o by

John

Woz

niak

Photo by Mark Claesgens

The harvested cane is loaded into trailers and taken to mills, such as this one in St. James. There are 17 mills in Louisiana.

No one variety has had such an impact on theLouisiana sugar industry as LCP 85-384. BehindKenneth Gravois is the variety.

Louisiana’s Sugarcane IndustryKenneth Gravois

Louisiana’s Sugarcane Industry


Sugarcane PestsSugarcane diseases have long

plagued the sugar industry in Louisianaand nearly caused its demise in the1920s. Jeffrey W. Hoy, LSU AgCentersugarcane pathologist, has worked tokeep new sugarcane diseases at bay.Since the late 1970s, four sugarcanediseases have moved into South Louisi-ana. First was rust. Its control has beenmainly through disease-resistantvarieties. Then sugarcane smut wasintroduced in the early 1980s, and one ofLouisiana’s most promising varieties ofthe time, CP 73-351, had to be removedfrom cultivation. In the early 1990s, leafscald disease was detected, and morerecently, yellow leaf syndrome wasfound in sugarcane fields in Louisiana.Varietal resistance has been the primarymeans of sugarcane disease control, andthe sugarcane pathology program worksclosely with the breeding program tominimize the disease impact.

Ratoon stunting disease (RSD),however, cannot be controlled throughresistant varieties. To help control thisdisease, Hoy established the SugarcaneDisease Detection Laboratory in 1997.Because of this lab, farmers can rely onobtaining healthy seedcane, which is theprimary means of RSD control. Asindicated in this issue of LouisianaAgriculture, the AgCenter, along withCertis USA, provider of Kleentekseedcane, and the Louisiana Departmentof Agriculture and Forestry, has helpedturn the tide against a disease that hascaused significant losses in sugarcanefor many years.

Hoy also led the AgCenter’sresearch efforts with billet planting.Billets are the cut pieces of stalkproduced by a combine harvester.Sugarcane in Louisiana has traditionallybeen planted using whole stalks, whichhelped control stalk rot diseases. Withcombine harvesters, farmers have thecapability of planting billets instead ofwhole stalks. However, Louisiana’scold, wet winters and stalk rot diseasesmake the success of billet planting moretenuous. Hoy’s work has outlined stepsthat help ensure success with billetplanting, such as using longer billetlengths and proper combine harvestersettings.

Louisiana’s most common sugar-cane insect pest is the sugarcane borer.Insecticides have long offered the maincontrol for this pest. In the early 1990s,however, environmental problemsbecame apparent with the availableinsecticides. Eugene T. “Gene” Reagan,

LSU AgCenter entomologist, beganlooking for safer alternative insecticidesand other means of sugarcane borercontrol. After screening several experi-mental insecticides, Confirm waslabeled for use in controlling sugarcaneborers. The new insecticide is specific,controlling only the sugarcane borerwithout destroying beneficial predatorinsects. Confirm also is safe for theenvironment, eliminating off-targetproblems. Through a system of inte-grated pest management safe for theenvironment, sugarcane borers arenow effectively controlled.

Weed ControlBecause successive crops of

sugarcane are grown from a singleplanting, weed control is a majorconcern. Until recently, the introductionof new herbicides for sugarcane wasrare. James L. Griffin leads the LSUAgCenter’s efforts in evaluating newherbicides and control measures forweeds encountered by Louisiana’ssugarcane producers. Several newherbicides are being evaluated to givefarmers more weed control options.Griffin’s work also includes getting themost out of currently labeled herbicides,such as fine-tuning conditions forjohnsongrass control with asulam. Inaddition to this work, sugarcane variet-ies are tested for tolerance to all herbi-cides so that yield potential is notdecreased at the expense of weedcontrol. To realize the maximumpotential of sugarcane, careful weedcontrol is a must.

Other LSU AgCenter sugarcaneproduction research includes soilfertility, rotational crops, cold tolerance,engineering and economic studies. Withfertilizer prices increasing because ofrising natural gas prices, efficient useof fertilizers is of utmost importance.William B. Hallmark and Charles W.Kennedy address research issues tomake the most out of fertilizer inputsand other soil amendments. BothHoward “Sonny” Viator and Griffinhave looked at some of the positiveaspects of growing soybeans in thefallow year of the sugarcane crop cycle.Opportunities for increased weedcontrol and supplementary income fit inwell with sugarcane farming practices.Benjamin L. Legendre, extensionsugarcane specialist, conducts coldtolerance studies. Sugarcane harvest inLouisiana can often occur after a killingfreeze. Legendre’s work providesinformation regarding how well differ-

ent sugarcane varieties can withstandfreezing temperatures. Michael P.Mailander is partnering with CamecoIndustries, Inc., to develop a yieldmonitor for sugarcane combine harvest-ers. The ability to map sugarcane yieldswill help farmers accurately determinefield yields and identify low yieldproduction areas within a field. MichaelSalassi leads the AgCenter’s efforts onthe economics of sugarcane production.Economic analyses, such as optimizingcrop cycle length, the feasibility ofprecision land leveling and annualsugarcane budgets, are just a few ofhis projects. With falling sugar prices,careful attention to production costs is amust if sugar producers and processorsare to survive.

Producing sugarcane with minimaladverse environmental effects isreceiving increased research attentionwithin the LSU AgCenter. Magdi Selimand Richard Bengtson have conductedstudies on the fate of pesticides andsediment in runoff water during sugar-cane cultivation. Their efforts nowinclude studies to determine the waterquality effects of maintaining the trashresidue after combine harvesting withand without burning. These studies areimportant in developing Best Manage-ment Practices (BMPs) for Louisiana’ssugarcane farmers. BMPs are voluntarypractices farmers use to improve waterquality in the surrounding environment.An AgCenter survey showed that manyof Louisiana’s sugarcane farmers areusing BMPs in their operations. TheAgCenter has also helped sugarcanefarmers learn to burn cane to minimizeenvironmental problems. Most of thesugarcane farmers in the state haveattended training workshops conductedby the AgCenter on controlled agricul-tural burning.

The Audubon Sugar Instituteconducts sugar processing researchwith the mission “to foster a center ofexcellence for applied and original sugarresearch, which exceeds the expecta-tions of our stakeholders in Louisianaand the international sugar industry,through innovative research, technologytransfer and education.” Peter Rein leadsthe research effort at the institute.Research goals include milling effi-ciency and a more diversified sugarprocessing industry.

Sugarcane production and process-ing are complicated businesses. TheLSU AgCenter is committed to conduct-ing research to meet the needs of thisvital South Louisiana industry.


PERSPECTIVE

he Louisiana sugar industry, withits long history and rich tradition, is avital component of the unique culture ofSouth Louisiana. The industry, whichcelebrated its bicentennial in 1995, ismade up of nearly 700 family farms thatproduced more than 1.5 million tons ofsugar from 460,000 acres of sugarcanein 2000. The economic activity resultingfrom the production of sugarcane and itsprocessing into sugar in Louisiana isestimated to be more than $2 billion peryear. To achieve this level of success,the sugarcane industry has relied onresearch to overcome many obstacles.Research will continue to play a vitalrole in the industry’s future success.

The climate of Louisiana hasalways challenged sugarcane producers.Louisiana lies at the northern limit ofthe sugarcane cultivation range. A shortgrowing season that can include droughtor hurricanes, a short harvest season thatcan be too wet, and a cold and wetdormant season challenge the vitalityof this tropical plant and create manyproblems affecting both production ofsugarcane and processing of the cane toproduce sugar. Because the risk of aplant-killing freeze increases in Decem-ber, the harvest must begin before thesugarcane reaches maximum sugarcontent. Old World varieties andvarieties produced for other regionsof the world do not grow well inLouisiana’s climate. Nevertheless,researchers building on the foundationslaid by their predecessors have bred,selected and released varieties uniquelysuited to Louisiana.

Changing economics and SouthLouisiana’s growing population aremaking the economic future of sugar-cane and sugar production uncertain.The industry faces stagnant or decreas-ing prices for the product, while thecosts of production and processingcontinue to increase. In addition, thepopulation continues to grow andencroach on production areas andmills, creating new problems related topesticide applications, burning of caneat harvest and transportation to themills.

Change is necessary for survival,and the sugarcane industry is responsiveto change fueled by research. Mostchange is prompted by problems, andresearch addressing the needs of theindustry has been continuous. Notewor-thy research accomplishments havealready occurred in the areas of newvariety development, photoperiodcontrol of flowering, cultural andfertility practices, integrated pestmanagement, weed control methodol-ogy, and development of diseasemonitoring and healthy seedcaneprograms. In recent years, the rate ofchange has accelerated dramatically.This is due in part to the release of ahigh-yielding variety, LCP 85-384, andthe adoption of a combine harvestingsystem. Higher yields are keeping theindustry in business, but the relatedshifts in methods for planting, cultiva-tion, harvest and processing havecreated many new questions thatresearch must address.

The LSU AgCenter sugarcaneresearch program has changed as itcontinues to address the current andfuture needs of the industry effectively.The breeding program has been consoli-dated at the St. Gabriel facility, and thestation has been re-named the SugarResearch Station. Significant financialresources were dedicated to obtaining a

combine harvesting system for thestation. The Audubon Sugar Institutehas reorganized and is undertaking bothresearch and teaching missions relatedto sugar processing. Research hasincreased on environmentally relatedprojects. The Sugarcane DiseaseDetection Laboratory was created toprovide disease monitoring for researchprograms and healthy plant material forcommercial seedcane production.Finally, programs addressing all of theother areas related to sugarcane produc-tion are being maintained.

In summary, the continued well-being of Louisiana’s important sugarindustry depends on research, and theLSU AgCenter sugarcane researchprogram is dedicated to making sure theLouisiana industry remains competitiveand continues to produce sugar foranother 200 years.

Freddie A. Martin, Head, Department ofAgronomy, and Jeffrey W. Hoy, Professor,Department of Plant Pathology and CropPhysiology, LSU AgCenter, Baton Rouge, La.

Freddie A. Martin

Jeffrey W. Hoy

Photos by John Wozniak

T

An Important IndustryFacing Many Challenges

Sugarcane:

Freddie A. Martin and Jeffrey W. Hoy



echanization of the harvest was a major turning pointin the history of sugarcane production in Louisiana. Harvest-ers were developed that would cut whole stalks of sugarcaneand drop them across rows on the ground to be picked up andplaced in transport wagons. This system was used for manyyears.

Within the last five years, however, another major changehas occurred in the sugarcane harvesting system used inLouisiana. Sugarcane is now harvested with what are knownas “chopper” or “combine” harvesters that cut cane stalks intosections or “billets” as they pass through the machine. Thebillets are carried up an elevator and then dropped into awagon traveling alongside.

This type of harvesting system offers several advantages.Sugarcane can be cut without burning, and it never touchesthe ground. Burning and contact with the ground both canaccelerate deterioration and sugar losses in cane stalks. In

Jeffrey W. Hoy, Professor, Department of Plant Pathology, LSU AgCenter,Baton Rouge, La.

M

Planting Sugarcane:

Photo by John Wozniak


In the 1940s, this was the latest in technology—a mechanical wayto harvest green cane. From the LSU AgCenter archive.

This is green cane being harvested as billets.

Whole Stalks Versus BilletsJeffrey W. Hoy


addition, and of even greater significance to farmers, this typeof harvester can more effectively pick up sugarcane that has“lodged” or fallen down. This then makes it possible to growhigh tonnage sugarcane varieties that typically lodge by theend of the season. Because the old, whole-stalk harvesterscould not handle high tonnage, lodged cane, varieties of thistype could not be developed by the sugarcane breedingprogram. As mentioned in other articles in this issue, theability to grow new, heavy tonnage varieties is increasing theyields obtained by Louisiana sugarcane farmers and keepingthem in business.

Climate Affects Planting MethodCombine harvesters have been used in most other places

around the world for many years, but they were evaluatedseveral times in the past in Louisiana and deemed a failure.The problem was the climate. Sugarcane is grown at thenorthern limit of its cultivation range in Louisiana, so thegrowing season is short. The crop must be harvested before akilling freeze occurs. As a result, the harvest must take placeduring a short period of time and must proceed even in wetweather.

Because early versions of combine harvesters boggeddown in the muddy fields, the Louisiana industry kept usingwhole stalk harvesters. In addition, whole stalks were neededfor planting to help control a disease called stalk rot (Figure 1)

rot will progress through the entire stalk than with the shorterbillets. In addition, a higher planting rate (more stalks planted)is used than in other regions of the world to be able to sustainlosses to stalk rot and still be able to establish an adequatespring shoot population. This expensive planting system wasadopted to ensure that adequate plant cane stands are estab-lished each year.

Billets are planted in other places around the world, butplanting billets also has been evaluated in the past in Louisi-ana and deemed to be too risky because of the greater poten-tial for stand failures. Yet, with the increasing use of combineharvesters, there has been intense, renewed interest within theindustry in finding methods that would allow successful billetplanting. It is expensive to maintain two harvesting systemsjust to be able to cut whole stalks for planting. In addition,there are advantages associated with billet planting. Laborrequirements are reduced with mechanical planting, and thecurrent mechanical planters plant billets more effectively thanwhole stalks. Planting billets goes rapidly, and the amount oftime and labor required for planting is reduced.

Switching to BilletsConsidering the failures of the past, is there any reason to

think that billet planting would be more successful this time?One difference is in the varieties being grown. Many of thenew sugarcane varieties have come from what is known asbasic breeding, in which agronomically desirable sugarcanevarieties are crossed to wild relatives with plants consistingof large numbers of grassy, small-diameter shoots. The basicbreeding program has been conducted by the USDA Sugar-cane Research Unit in Houma, La., for more than 30 years.The material generated by this program is used in the Louisi-ana Sugarcane Breeding Program, which is a cooperativeeffort among the LSU AgCenter, USDA’s AgriculturalResearch Service and the American Sugar Cane League. Thehigher shoot populations and increased vigor of some of thenew varieties could affect billet planting performance. Inaddition, new fungicides and other types of biological andchemical treatments are available that might reduce stalk rotseverity.

A research project evaluating factors affecting billetplanting has been conducted cooperatively by the LSUAgCenter, the American Sugar Cane League and sugarcanefarmers for the last six years. The early field experimentsdemonstrated that varieties vary in tolerance of billet planting,and this offers some hope for breeding and selecting forvarieties that can be successfully planted as billets. Unfortu-nately, no chemical or biological treatment has been identifiedthat will control stalk rot and improve billet planting perfor-mance. Instead, a series of cultural practices that indirectlyreduce disease severity and promote vigorous plant growthhas been identified that will maximize the chances of successin billet planting.

Planting BilletsBillets are more sensitive than whole stalks to stress

conditions. This is because stalk rot severity is increased bystressful conditions such as drought or water-logging. As aresult, good planting practices are essential for billets. Theseinclude proper soil preparation and depth of cover, establish-ment of good drainage and careful weed control. Addingfertilizer at planting has been beneficial in most experimentsand continues to be evaluated.

Figure 1. These stalks have been dug up and split open exposingstalk rot.

that rots planted sugarcane and can severely reduce springshoot populations and yield. Stalks of sugarcane are planted inthe late summer, and bud germination and shoot elongationbegin in the fall. The occurrence of frosts and freezes duringwinter then kills the above-ground growth, and the plantedstalks and young shoots must sit in the cold, wet ground forseveral months. Severe stalk rot can result in a stand failureand necessitate replanting.

The failure to establish a plantcane (first year) crop is theworst loss a farmer can sustain. When the previous crop isplowed out, the land does not produce a crop during thatseason. Then, the stalks used for planting represent a loss,since that cane would have been harvested and sent to the millfor sugar extraction. With whole stalks, it is less likely that the

Photos by R. Judice


Other important factors affecting billet planting perfor-mance are related to the type and amount of billets used forplanting. Normal billets cut during harvest for the mill areabout 10 inches long. The harvester must be modified to cutbillets 20-24 inches for planting. In addition, it is important tominimize physical damage to the billets, because the patho-gens that cause stalk rot gain entry to the internal stalk tissuesthrough wounds. Planting a longer billet with minimal damagewill reduce the severity of stalk rot. Research is identifyingharvester modifications that will reduce damage and producethe highest quality billet possible.

Finally, the rate of planting affects billet planting (Figure2). Cutting and planting more seedcane is expensive, buthigher rates of planting are needed with billet planting. Billetplantings must be able to sustain stalkrot damage and still produce anadequate stand.

The research results have shownthat whole-stalk planting will producethe maximum yield over multiplecrops and years with the least risk.Thus, it will continue to be a recom-mended practice. However, severestand problems have not been encoun-tered with billet planting when usingthe practices described above. Inaddition, the new high-yieldingvariety, LCP 85-384, has shown sometolerance of billet planting. As aresult, billet planting will now berecommended as an alternative towhole-stalk planting. Billet plantingmay offer some advantages overwhole-stalk planting that would beattractive to some farmers, but perhapsthe greatest factor leading to arecommendation for billet planting isthat severe lodging before the planting

Figure 2. Higher rates of planting are needed with billet planting. Billet plantings must be able to sustain stalk rot damage and stillproduce an adequate stand.

season is common with high tonnage varieties, such as LCP85-384. Whole-stalk harvesters cause extensive damage tobadly lodged cane, so the best option in this case will be to cutand plant billets.

Farmers would prefer to plant billets, but many keep awhole-stalk harvester in working condition to cut seedcane ifthe stalks are standing. Caution is still in order. However, ifmethods for successful billet planting are proven, the Louisi-ana sugarcane industry will rapidly switch to billet planting.Planting billets under Louisiana growing conditions is achallenge. The LSU AgCenter conducts research to meet thatchallenge.

This field has been planted in billets.


A sugarcane variety begins as a single seedling. Stalksfrom that initial plant are then cut and planted, and the budsalong the stalks germinate and grow to produce new plants.This increase through cutting and planting of stalks, or“seedcane,” continues until the variety may be grown in manyfields across the state. In each field, all plants are identical tothe first. This increase process known as “vegetative propaga-tion” creates the potential for disease problems, because somediseases can be spread to new fields and increased during theplanting process.

Certain types of plant pathogens become distributedthroughout infected plants. When this occurs, any infectedstalk cut and planted will produce multiple new diseasedplants. To control this systemic disease, farmers need to beable to obtain and plant healthy seedcane. Extensive, long-term research has been directed toward developing methodsthat will allow growers to control systemic diseases on theirfarms with a healthy seedcane program. In recent years, asuccessful disease control program has been developedthrough a partnership between the public and private sectors.

Ratoon Stunting DiseaseA healthy seedcane program is needed to manage ratoon

stunting disease (RSD), the most important disease affectingsugarcane in Louisiana. The term ratoon refers to the crop ofstalks that re-grows from the base of plants left in the soilafter harvest. In Louisiana, farmers typically obtain fourannual cuttings of stalks from one planting—the plantcane(first year) crop and three sequential ratoon crops. Thepathogen that causes RSD is distributed throughout the plantin the water-conducting vessels (Figure 1). Under adversegrowing conditions, particularly drought, the growth ofinfected stalks is stunted and yield is reduced. The stuntingand losses become progressively more severe in the ratooncrops. Because there are no visible symptoms of the disease,only reduced growth, farmers do not know when they haveRSD or when they are spreading it.

One factor contributing to RSD persistence was the lackof a reliable detection method that would allow diseasemonitoring. However, since 1997, a detection method for RSDmonitoring has been available through the Sugarcane DiseaseDetection Lab, which is operated under the auspices of theLSU AgCenter with financial support from the AmericanSugar Cane League and the company producing Kleentekseedcane. The detection method used is a tissue-blot immu-noassay in which cross-sections of stalks are blotted onto amembrane, and antibodies produced against the RSDpathogen are used to determine whether a stalk has RSDor not (Figure 2).

Control Requires Healthy SeedcaneMany sugarcane diseases have been controlled through

the development of resistant varieties, but this has not beenthe case for RSD. This disease can be controlled only withhealthy seedcane programs. The first program developed usedheat treatment on stalks to be used for planting. Dipping stalksin water at 122 degrees F for two hours can eliminate most butnot all RSD infection without causing extensive damage to thestalks. Heat treatment must be performed carefully. Lowertemperatures will not control the disease effectively, andhigher temperatures will damage stalks. The logistics oftreatment (time, personnel and unit capacities) limit seedcaneoutput, and multiple field increases are needed to provideenough seedcane to meet planting needs. These factors, alongwith occasional stand problems, resulted in limited use of heattreatment in Louisiana and persistence of RSD.

Tissue CultureThe development of a technique to mass propagate plants

in the laboratory known as “tissue culture” provided anotheroption for producing healthy seedcane for sugarcane farmers.The potential use of seedcane produced through tissue culturebegan to be examined in 1984 with the introduction of acommercially produced seedcane using the product nameKleentek. Experiments comparing agronomic performancebetween Kleentek and traditional sources demonstratedKleentek yields were similar or superior to the original.

Concerns about quality assurance for a commerciallyproduced seedcane were addressed with the development ofcertification standards to be regulated by the LouisianaDepartment of Agriculture and Forestry (LDAF). Input fromKleentek, the American Sugar Cane League, the LSUAgCenter, the U.S. Department of Agriculture and LDAF wasused to formulate regulations covering accession of sourcematerial for tissue culture, limitations for stand eligibility andlimits for tissue culture variants, insect damage, weeds andcertain diseases.

Even though RSD control was the primary objective, itwas not included in the certification standards because of thelack of reliable symptoms. However, since 1997, an indepen-dent assessment of the RSD status of Kleentek seedcane has

Jeffrey W. Hoy, Professor, Department of Plant Pathology, LSU AgCenter,Baton Rouge, La.

ControllingDisease

Jeffrey W. Hoy

Figure 1. At left is a close-up of the RSD pathogen as seen throughan electron microscope. In the center is a cross-section of avascular bundle in a sugarcane stalk. The two largest holesvertically in the center are water vessels where the RSD pathogensoccur. At right is a view of the RSD pathogens on the interior wallof a water vessel, which may become plugged.


Photos by K.E. Damann Jr.

been performed by the Sugarcane Disease Detection Lab.After several changes in the parent company for Kleentek,local representatives negotiated a partnership with the LSUAgCenter in which the tissue culture lab became an LSUfacility operated by Kleentek. Seedcane production anddistribution remained the responsibility of Kleentek. A “localquarantine” operated by the Sugarcane Disease Detection Labnow provides healthy plant material of experimental varietiesfrom the Louisiana Sugarcane Breeding Program for tissueculture.

LCP 85-384’s EffectA final component of the research effort to control RSD

was the determination that varieties vary in rates of spread andincrease of RSD. Experiments demonstrated that the high-yielding sugarcane variety, LCP 85-384, has some resistanceto the spread of RSD. This type of disease resistance has had apositive impact on RSD control. The RSD testing done by theSugarcane Disease Detection Lab over the last four years hasdocumented that RSD levels in the industry have fallen. Thefactors associated with reductions in RSD are increasedplanting of LCP 85-384 and use of Kleentek seedcane.

A large-scale RSD survey conducted statewide during2000 on more than 120 farms detected RSD in 14 percent of535 fields tested, and the average stalk infection level withinfields was 2 percent. This is in contrast to a survey in 1986

Figure 2. Testing for bacteria that cause RSD involves cuttingsamples from a core removed from a sugarcane stalk (left). Thesesamples are then fitted into a special tray and pressed onto a

that showed that 59 percent of the fields were infected withinfection levels in the fields averaging 22 percent. Althoughthe 2000 survey results indicate significant progress in RSDcontrol, RSD was detected in at least one field on 35 percentof the farms tested. This means RSD is still present in the in-dustry, and active control measures still need to be continued.

Several additional systemic diseases can be spread duringsugarcane planting, including leaf scald, mosaic and yellowleaf. Mosaic has been a problem for many years. Leaf scaldfirst appeared in 1992. Yellow leaf has been observed onlywithin the last few years. These diseases have other means ofspreading besides planting. Leaf scald can be spread in wind-blown rain, and mosaic and yellow leaf are spread by insects.Having a source of seedcane containing little or no disease canreduce the impact of these diseases as well as RSD.

In Louisiana, on-farm healthy seedcane programs usingcommercial seedcane produced through tissue culture and thegrowth of varieties with lower rates of spread of RSD havebrought about a high degree of control of what has historicallybeen the most damaging disease of sugarcane. This has beenaccomplished through a partnership among farmers, the LSUAgCenter, a state regulatory agency (LDAF) and a commer-cial seedcane company. In addition, a joint approach ofbreeding for disease-resistant varieties, together with a healthyseedcane program based on tissue culture, is providing controlof the other important sugarcane diseases in Louisiana.


blotting paper (the three sheets at right). Antibodies producedagainst the pathogen will be used to determine whether or not thebacteria are present. All together the test takes about two days.


Preparing to ReplantAfter several years, weeds, diseases

and insects take their toll on sugarcanestands, and it is no longer economical tokeep stubble for another year. Thestubble is destroyed, and the fieldprepared for replanting. This summerfallow period from May to September iscostly to the farmer because there willbe no crop to harvest until the followingyear, but inputs (tillage and herbicide)are necessary to prepare the land forreplanting. Additionally, seedcane usedto replant fallowed fields reduces theamount of sugarcane that wouldnormally go to the mill for processing.

The summer fallow period isprobably the most important phase ofthe sugarcane production systembecause this is when the grower has theopportunity to reduce weed infestationssignificantly. The most problematicweeds in sugarcane are the perennials,johnsongrass and bermudagrass, whichsurvive from year to year by producingan underground network of fleshy stems,known as rhizomes. Since the soil on therow top where the sugarcane grows canremain virtually undisturbed for up tofive years, these perennials can becomewell established and almost impossibleto control without causing significant

James L. Griffin,Blaine J. Viator,Patrick A. Clay,Jeffrey M. Ellis,

Donnie K. Miller,Stacey A. Bruff,Andrew J. Lanie

and Reed J. Lencse

eeds are a major factorlimiting production of sugarcanein Louisiana. The battle for water,light, nutrients and space betweenweeds and the crop can reducesugarcane stalk population andyield. Sugarcane differs from othercrops in that at least three harvests,and in some cases four to fiveharvests, are made from a singleplanting. Because the soil on therow top where the sugarcane growsis not appreciably disturbed duringthe multi-year crop cycle, weedscan become well established anddifficult to control.

Although the herbicideslabeled for use in sugarcane havenot changed much in the past 12years, LSU AgCenter research onherbicide use in combination withcultural practices and tillage hasproduced new recommendationsfor farmers. Several new herbicideswith novel modes of action arebeing evaluated and should beavailable to producers within thenext few years.

crop injury. Additionally, over time,annual weeds produce abundant seedthat assures their continued presence.

The fallow period allows the groweropportunity to reduce weed seed andrhizomes in the soil to help get thenewly planted crop off to a good start.Programs that can be used during thefallow period include frequent tillage(opening and closing of beds) to destroyemerged seedlings, use of soil-appliedherbicides to prevent weed reinfestationand use of glyphosate products(Roundup Ultra, Roundup Ultra Max,Roundup Original, Glyfos, Glyfos-Xtra,Glyphomax Plus, Gly-Flo, GlyphosateOriginal, Touchdown and others). Allcan be effective, but in most caseswhere johnsongrass and bermudagrassare problems, glyphosate is necessary.Under limited rainfall conditions,frequent tillage can deplete moisture inthe seedbed, resulting in delayedemergence and establishment of plantcane.

Another option during the summerfallow period is to plant early-maturing,glyphosate-resistant (Roundup Ready)soybeans on sugarcane beds and useglyphosate for weed control. Anotherarticle in this issue addresses thebenefits of this alternative program.

Summer

Following the last cultivation at layby in May, herbicide is broad-casted and directed underneath the sugarcane canopy. Applicationof herbicide at this time, combined with shading from the cropcanopy, can reduce emergence and establishment of weeds.

Spartan, a new soil-applied herbicide, is effective on morningglories(tie-vines) when applied at layby and has eliminated the need forlate-season 2,4-D applications.

W

Photos by James L. Griffin

Weed Control:Weed Control:


James L. Griffin, Professor, and Blaine J. Viator,Patrick A. Clay, Jeffrey M. Ellis, Donnie K.Miller, Stacey A. Bruff, Andrew J. Lanie and ReedJ. Lencse, all former graduate students, Depart-ment of Plant Pathology and Crop Physiology,LSU AgCenter, Baton Rouge, La.

Grass ThreatWhen johnsongrass, itchgrass and

annual grasses are not controlled withthe soil-applied spring treatments,growers can make a postemergenceapplication of Asulox/Asulam. Theseherbicides can be applied broadcast,banded or as a spot treatment over thetop of sugarcane. Johnsongrass controlwith these herbicides can be erraticsince environmental conditions greatlyimpact herbicide uptake into the plant.A characteristic yellow discolorationand stunting occur with johnsongrass.Weed control is slow, often requiringas long as six weeks, before weeddeath occurs.

For best results, actively growingjohnsongrass should be 12 to 18 inchestall and other grasses no more than 8inches tall. With some variation causedby weather conditions, johnsongrasswill be at the recommended treatmentsize in most years during April.Johnsongrass control can be reducedif the root system is disturbed bycultivation or fertilization seven daysbefore or seven days after Asulox/Asulam application. A 20-hour, rain-free period following herbicideapplication may be needed to maxi-mize johnsongrass control.

A second application tojohnsongrass regrowth, usually abouteight weeks after the first application,can enhance control but may notincrease yields more than a singleapplication. The variety LCP 85-384has shown sensitivity to Asulox/Asulam (yellowing and stunting)when temperatures are high and whenapplications are made after May 15.

Watch WeedsIn winter, when sugarcane is

dormant, weeds in some fields caninclude the winter annuals, Italianryegrass, timothy, rescue grass, annualbluegrass and an assortment ofbroadleafs including Carolina geranium,sowthistle, marsh parsley and others.Left uncontrolled, they will remain inthe sugarcane crop until May or laterwhen they mature and set seed. Winterweeds can interfere with early growth ofsugarcane as it emerges from thedormant period. Broadleaf weeds areeasily controlled with 2,4-D (sold undervarious trade names) or Weedmaster/Brash (2,4-D + dicamba mixtures).Control of winter grasses and certainbroadleafs can be obtained withparaquat formulations such asGramoxone Extra/Gramoxone Max/Boa.Advantages to removing winter weedsinclude earlier emergence and morerapid growth of sugarcane, increaseddrying of fields, more efficient tillageoperations, and greater use of fertilizerby the crop. The Gramoxone Extra/Gramoxone Max labels allow for useon emerged cane up to the 4-leaf stage.Sugarcane injury with this treatment can

be significant but is short-termand not detrimental to yield.

In March and April, thegrower will use a soil residualherbicide to reduce competi-tion of summer weeds. Weedsemerging with the crop inspring can reduce tillering ofcane and hinder growth, oftenresulting in reduced yields atharvest. In most cases herbi-cides are applied to a narrowband on the top of the row,rather than broadcast, to reducecost per acre. Various herbi-cides including trifluralinproducts that require incorpo-ration along with Sencor,Prowl, Pendimax, Sinbar,Aatrex/Atrazine, Karmex/Direx and Sempra are labeledfor use. Some growers maychoose to combine paraquat or2,4-D with the soil-appliedtreatments to eliminate a tripover the field.

Planting Period CriticalFollowing the summer fallow,

sugarcane is planted in August andSeptember using whole stalks or cutstalks (billets). This phase is criticalbecause uncontrolled weeds haveenough time before the first killing frostto reestablish and produce rhizomes orseed. If this occurs, efforts to reduceweed populations during the fallowperiod are nullified. Typically, soil-applied herbicides are used afterplanting but before cane emerges.Trifluralin products (Treflan, Trifluralin,Trilin, Tri-4 and Trific) require incorpo-ration or mixing with soil covering thesugarcane seed to prevent herbicide loss.Other herbicides (Sencor, Prowl,Pendimax, Sinbar, Velpar plus Karmex/Direx, Aatrex/Atrazine or Karmex/Direx) can be applied to the soil surfaceand do not require mechanical incorpo-ration. The combination of Commandplus Karmex/Direx recently received alabel for bermudagrass control whenapplied after planting and beforebermudagrass is reestablished. Withmany of these herbicides, depending onthe time of application and rate, controlof some winter weeds can be expected.

Fall Winter and Spring Early Summer

Bermudagrass reinfesting row middles followingplanting or after early cane harvest can be controlledin mid-October with glyphosate products appliedunderneath a hooded or shielded sprayer thatprevents spray contact with sugarcane foliage.

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Essential to Sugarcane ProductionEssential to Sugarcane Production


Planning HerbicidePrograms

Knowledge of specific weedproblems and cultural practices iscritical to planning cost-effectiveweed control programs. Theregistration status of herbicides israpidly changing. Weed controlrecommendations in sugarcane arepublished annually in the LSUAgCenter publication titled“Louisiana Suggested ChemicalWeed Control Guide” and are basedon research conducted by weedscientists in the LSU AgCenter andwith USDA. This publication isavailable online at the LSUAgCenter’s Web site and fromany parish extension office.

Fall TreatmentIn sugarcane planted in August and

September and in sugarcane harvestedfor seed or harvested in September forearly delivery to the mill, bermudagrasscan reestablish before the winterdormant period. One excellent option isto apply Roundup or other glyphosateproducts to the row middles using ahooded or shielded sprayer in mid-October. This treatment has signifi-cantly reduced bermudagrass infestationthe following year. Growers should usecaution, though, because severe sugar-cane injury can occur if glyphosatecomes in contact with green canefoliage.

Asulox/Asulam may be appliedaround mid-October to early plantedor early harvested sugarcane to controlemerged johnsongrass. This has been aneffective treatment even when herbiciderates are reduced compared with thoseused in April and May. Significantreductions in johnsongrass have beenobserved the next spring.

The reason for the effectiveness ofglyphosate products and Asulox/Asulamis that in the fall, when days becomeshorter and nights cooler, perennialplants like bermudagrass andjohnsongrass begin to move foodreserves to the rhizomes for wintersurvival. Herbicide applied at this timemoves readily within the plant alongwith the food reserves to the rhizomeswhere it inhibits growth.

Late-season TreatmentsWeeds that escape the layby

treatment may, in some cases, requirecontrol measures for efficient harvest ofthe crop. Late-season herbicide applica-tions are most often made by air in lateJune through August and involve use of2,4-D products. 2,4-D is effective onmorningglories, if the rate is matched tothe weed size. Even though a pint peracre is effective on 2- to 3-leaf plants,1.5 quarts per acre is needed if vines areclimbing sugarcane plants. Encroach-ment of residential areas and legalrestrictions in some parishes prohibituse of 2,4-D for late-season control.

Use caution when applying 2,4-Dto sugarcane for seed. For some of theolder sugarcane varieties, 2,4-D appliedwithin four weeks of cane harvest forseed resulted in significant reductions inplanted stands both in the fall and thenext spring. LSU AgCenter researchersare investigating the effect of 2,4-Dapplication timing on LCP 85-384planted using both whole stalks andbillets.

To control bemudagrass reinfestingrow middles, Gramoxone Extra/Gramoxone Max/Boa can be applied as

a directed spray in late Juneand early July. To avoidsignificant injury to youngcane, herbicide should beapplied with a high clearancesprayer with spray solutiondirected to the stalk bases tocover weeds. This desiccatesbermudagrass and, combinedwith shading from the cropcanopy, can prevent or reducebermudagrass reinfestation andtransport in sugarcane used forplanting.

Last Run-through: LaybyLayby is the term generally used to

describe the farmer’s last crop run-through. At layby in late April and May,sugarcane is cultivated for the last time,and a soil-applied herbicide is used tokeep fields weed-free until harvest.Various trifluralin products that requireincorporation and Sencor, Prowl,Pendimax, Sinbar, Aatrex/Atrazine,Karmex/Direx and Sempra are labeled.Herbicides are applied broadcast anddirected underneath the crop canopy toavoid contact with the young leaves inthe top of the plant. Weeds that escapethe layby herbicide treatment generallyare not yield-limiting but can reestablishand set seed, causing problems thefollowing year.

The morningglory group of weeds,referred to as tie-vines by growers, canbe a particular problem after layby,especially red morningglory. Theseweeds, capable of climbing and forminga dense mat over the crop canopy, createdifficulty during harvest, especially forcombine harvesters. Red morninglorycan be controlled preemergence at laybywith Spartan, a new herbicide recentlyapproved.

AcknowledgmentThe American Sugar CaneLeague provided partial fundsto support this research, whichover a 12-year period contrib-uted to thesis projects forseveral graduate studentsworking in cooperation withEd Richard, U.S. Departmentof Agriculture, Houma, La.

Layby Late Season Fall

The morningglory group of weeds, which farmerscall tie-vines, can be a particular problem afterlayby, especially red morningglory. These weeds,capable of climbing and forming a dense mat overthe crop canopy, create difficulty during harvest,especially for combine harvesters.

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Only a small percentage of the more than 75,000 acres of sugarcanefallow land in Louisiana is planted annually to rotational crops. Mostsugarcane growers traditionally have used the fallow period for threepurposes: to control troublesome weeds like johnsongrass, itchgrass andbermudagrass; to reform the land to facilitate drainage; and to rejuvenate thesoil. Grower interest in rotational crops, however, has surfaced with theavailability of glyphosate-resistant (Roundup Ready), early-maturing GroupIV soybean varieties that can be grown on fallow land either as a cover cropor a cash crop.

Studies conducted at the LSU AgCenter’s St. Gabriel Research Stationindicate that johnsongrass control in fallowed sugarcane fields planted toglyphosate-resistant soybeans grown as a cash crop compared favorably withthat of a non-crop, conventional tillage herbicide program. Subsequent yieldsof sugarcane for the fallow-period management treatments were equivalent.Preliminary results on the evaluation of itchgrass and bermudagrass controlin glyphosate-resistant soybeans look promising.

Researchers at the LSU AgCenter’s Iberia Research Station conducteda series of experiments designed to estimate the nitrogen fertilizer value ofgreen manure soybeans (cover crop) for exploitation by succeeding sugar-cane crops. They found that little fertilizer credit could be assigned to thegreen manure. It is postulated that the excessive length of time betweensoybean plow-down in late summer or early fall and the resumption ofsugarcane growth the following spring diminishes the availability of organicnitrogen from soybean residue.

Researchers found no difference in sugar yield between the conventionalfallow and soybean green manure treatments. The absence of fertilizer valuefor green manure soybeans should not condemn the practice of plantingsoybeans during the fallow period. The current focus on the protection ofsoil and water resources provides an additional incentive for the use of acover or cash soybean crop as a Best Management Practice (BMP) for erosioncontrol. Additional benefits include maintenance of soil organic matter andopportunity for cash flow from harvested soybeans. Also, economic analysesindicate the costs associated with producing a soybean crop could besubstituted for standard fallow activity and seedbed preparation costs. Ofcourse, this substitution is predicated on the ability of growers to controlweeds and adequately prepare a seedbed for late summer sugarcane planting.

Growers must be aware of problems that may be encountered withsoybeans grown in rotation with sugarcane. Most often, poor sugarcanestands following green manure soybeans are attributable to obvious causeslike stalk rot, cut worms, persistent weeds and possibly nematodes. Weakstands also may result from planting sugarcane too quickly after incorporatinggreen manure. Another significant concern is delayed maturity of soybeansgrown as a cash crop. Physiologically distressed soybean plants, which remaingreen beyond normal maturity date, delay timely harvesting and subsequentplanting of sugarcane.

Recently confronted with sugar prices at or below the cost of produc-tion, sugarcane growers need to consider diversification as a means ofincreasing the cost effectiveness of their farming operations. The productionof soybeans in the fallow period offers an economically sound option forconserving topsoil, controlling weeds and generating income.

Fallow period cropping to soybeans can provide benefits

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The fallow field at right was planted in soybeans.

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The sugarcane at right, which is thicker andgreener, was planted following Roundup Readysoybeans. Research, however, shows no long-term residual nitrogen value.

Sugarcane farmers typically plant two rows(drills) of soybeans per sugarcane row.

Growers may choose varieties of differingmaturity for timely sugarcane planting. Thefield on the right is early maturing and will beharvested sooner.

Howard P. “Sonny” Viator, Resident Director, Iberia Research Station, Jeanerette, La., andJames L. Griffin, Professor, Department of Plant Pathology, LSU AgCenter, Baton Rouge, La.

Fallow period cropping to soybeans can provide benefits


ntegrated pest management (IPM)has two distinctive components—economic protection from pest damageand a more favorable environmentaloutcome than would occur in the absenceof IPM. Integrated pest management is adynamic process and involves balanceamong biological, cultural and chemicalmeasures deemed most appropriate to aparticular situation after careful study ofall factors involved.

The U.S. Environmental ProtectionAgency (EPA) has encouraged selectionof Best Management Practices (BMPs)for major field crops. The BMP-devel-oped practices for sugarcane entomologyare to:

Use economic threshold levels ofpest insects to determine the needfor control.Monitor insects periodicallythrough scouting to determinewhen threshold numbers areexceeded.Use only appropriately labeledrates of chemical insecticides andat a time when the weather condi-tions most likely will help toachieve the best control withoutenvironmental harm.Plant insect-resistant varieties andtake other appropriate manage-ment actions to further reduceinsecticide usage, particularly inenvironmentally sensitive areas.Develop and implement manage-ment systems with narrow-range,minimum-risk insecticidechemistry.

I

16 Louisiana Agriculture, Fall 200116 Louisiana Agriculture, Fall 2001

T. Eugene “Gene” Reagan, Professor, Departmentof Entomology, LSU AgCenter, Baton Rouge, La.

A goal of LSU AgCenter entomol-ogy research is to improve IPM in theLouisiana sugarcane industry. Althoughseveral insects threaten sugarcane, thelarval stage of the sugarcane borer mothcauses the greatest amount of injury. Itis responsible for 90 percent of croplosses by insects. Because of adoption ofpest management practices, the averageannual number of insecticide applica-tions for control of the sugarcane borerhas decreased dramatically. For ex-ample, in 1960, the average number ofannual insecticide applications was 12;now it is slightly less than one.

Insecticide ManagementDuring the last 30 years, borer

resistance and environmental concernswith fish and bird kills caused thereview and termination of manyeffective insecticides in the sugarcane

Testing for varietal resistance to the sugarcaneborer involves counting the entrance and exitholes made by the pest. The smaller holes aremade by entering larvae; the larger, oval-shapedholes are created by the prepupa for theemerging moth.


T. Eugene “Gene” Reagan

Integrated Pest Managementin Sugarcane

Integrated Pest Managementin Sugarcane


immediately from insecticide-treatedfield plots. Only one material(tebufenozide) did not kill the parasites.

Scouting ChangesTo successfully implement this new

environmentally friendly technologyinto the sugarcane industry, laboratoryfeeding studies were conducted. Thiswork determined a sensitivity baselineand was used to show consultants thatthey could not rely on the traditionalapproach of making live and dead insectcounts three days after application. Withthis new chemistry, the borer quitsfeeding but may not die for several moredays.

LSU AgCenter research has shownthat the MAC chemistry provides thefirst effective insecticide for control ofthe sugarcane borer with compatibilityfor parasite releases in classical biologi-cal control programs. Experimental fielddata indicate an enhanced length-of-control period in succeeding applica-tions, because of both a less detrimentalinsecticide impact on beneficialarthropods and increased effects onother life stages of the borer. In 1998,the EPA presented its Presidential GreenChemistry Challenge Award to theinvention and commercialization of thisnew chemical family of insecticides,represented by Confirm.

industry. In 1993, LSU AgCenterresearchers began a study of a new classof insecticides called the MACs, or“molting accelerator compounds.”These insecticides affect larval growth.The first phase of the assessmentinvolved a five-replication, 2-acre,summer study on the St. GabrielResearch Station, where fire ant preda-tors are suppressed to allow for highborer infestations.

A follow-up experiment the nextyear involved a four-replication, 60-acreaerial application trial on a private farmin a heavy borer infestation area. In thistest, the impact on secondary pests (suchas the yellow sugarcane aphid) wasstudied along with length of control andyield loss from the sugarcane borer.Another important part of this study wasan assessment of beneficial insects andother non-target arthropods like cricketsand spiders. Fire ants eat crickets, whichalso help to sustain high numbers ofarthropod predators, including spiders.

From among many insecticidesevaluated in 1994 and 1995 (manycausing a significant two- to three-foldreduction of beneficial insects), the onlychemical not suppressing crickets andspiders was tebufenozide, which wassoon labeled as Confirm. In classicalbiological control studies, borer para-sites were exposed to leaves taken

The Mexican rice borer was introduced in 1980 fromMexico into the Lower Rio Grande Valley of Texas, where itsoon became a serious pest of sugarcane. In 1987, the Mexicanrice borer was detected in Jackson and Victoria counties of theTexas Rice Belt. In 2000, LSU AgCenter and Texas A&Mscientists cooperated in setting out pheromone traps todetermine the Mexican rice borer spread since 1987. Countyextension agents, farmers and personnel of both the LouisianaDepartment of Agriculture and Forestry and the TexasDepartment of Agriculture participated in monitoring thetraps. The pheromone traps used were baited with a syntheticpheromone to attract Mexican rice borer male moths.

Results of the 2000 trapping program in western Louisi-ana sugarcane and in East Texas show that the Mexican riceborer has moved into five new counties of the Texas RiceBelt—Wharton, Brazoria, Colorado, Waller and Ft. Bend.Two newly infested counties (Harris and Austin) were addedin the spring of 2001, placing the Mexican rice borer within 50miles of East Texas sugarcane, which has been transported formilling into Louisiana.

Mexican Rice Borer Threat

The narrow range of activity oftebufenozide is both an asset and aproblem because it does not controlsecondary pests in sugarcane. Otherinsecticides must be used for otherinsect pests and potentially for resis-tance management of the sugarcaneborer. As insecticide selection pressureincreases in an area, the need to alter-nate insecticide classes also increases.Several other insecticides are necessaryto control other sugarcane insect pests.Recently completed research on borerinfestation sampling will also assist withchanges in scouting procedures.

Soil InsectsPest management for soil insects in

sugarcane has not achieved the environ-mentally friendly nature of sugarcaneborer control. Economic thresholds havebeen established for wireworms. Butwhen chemical insecticides are needed,their impact has the potential forsubstantially enhancing sugarcane borerinfestations. Recent experimentsindicate that the usual rate of a com-monly used soil insecticide applied atfall planting can cause at least a 50percent reduction of crickets and a 30percent suppression of fire ants. Asshown in Table 1, even with approxi-mately two additional applications ofinsecticide for borer control, bored

T. Eugene “Gene” Reagan, Professor, Department of Entomology, LSUAgCenter, Baton Rouge, La., and M.O. Way, Associate Professor,Texas A&M University-Beaumont.

Sugarcane farmers in southeast Texas and southwestLouisiana are concerned about the possible introduction ofthe Mexican rice borer. In the Lower Rio Grande Valley ofTexas, the Mexican rice borer is still the No. 1 pest ofsugarcane. In fact, some fields are not harvested because ofheavy damage. Even though trapping data show that theapproximately 1,000 acres of sugarcane grown in Texas eastof Houston have remained free of the Mexican rice borer,farmers in both states are concerned about this pest. Datafrom the Lower Rio Grande Valley show that drought-stressed sugarcane is far more susceptible to the Mexican riceborer than healthy sugarcane. Most Louisiana farmers have nofacility to irrigate. Cooperative Mexican rice borer studies invariety plots show some potential for resistance with Louisi-ana varieties, but insecticide work has been less promising.


internodes averaged 17.8 percentcompared to less than 3 percent whensoil pesticide was not used. For mostvarieties, 0.75 percent bored internodeinjury is comparable to a 1 percent lossin sugar yield.

Varietal ResistanceIn addition to hot, dry weather

conditions, resistant varieties have thegreatest potential for reducing areawidepopulations of the sugarcane borer. Thepest management impact of varietiesevaluated in the LSU AgCenter’ssugarcane variety development programinvolves assessment five to seven yearsbefore release to the farmer. To predictthe impact of moth populations, both the

AcknowledgmentAppreciation is expressed to Dale Pollet,LSU AgCenter entomologist, and Bill White,entomologist with the U.S. Department ofAgriculture, Houma, La., for assistance andcooperation in this research.

Valueof NontargetOrganisms

Studying the impact on nontar-get organisms, especially insects thatare not pests of sugarcane, is animportant part of insecticide evalua-tion. This includes the effects onother insects from sprays to controlthe sugarcane borer and soil insecti-cides for wireworm control. The im-ported fire ant is so helpful to thesugarcane farmer that the predationit provides is equal to two insecticideapplications properly timed to con-trol the sugarcane borer. Thoughcrickets are neutral insects in sugar-cane fields (neither pest nor benefi-cial), they are important as food forpredatory fire ants. The tremendousbeneficial effects of these other in-sects living in the sugarcane ecosys-tem make it essential to developinsecticide programs with minimalharm on nontarget organisms. Fireants are thought of as a good first lineof defense against the invasion ofother sugarcane pests such as theseverely damaging Mexican RiceBorer, which may move intoLouisiana’s sugarcane from Texas.During late May, fire ants are alsothought to help protect sugarcanefields from the establishment ofFormosan subterranean termites fol-lowing adult mating flights. The ter-mite reproductives must first searchfor a nesting site. Fire ants can stopthem in their tracks.

Insecticides are applied to sugarcane fields via airplane. Photo by Gene Reagan

percentage of bored internodes (damageand yield loss), and the number ofdistinctive moth emergence holes arecounted. Adult (moth) production on anareawide basis is compared by countingemergence holes from each variety plot.Even though the high-yielding varietyLCP 85-384 is susceptible to thesugarcane borer, implementation of thenew tebufenozide chemistry in borermanagement has made the production ofthis susceptible variety more feasible.

Two New InsectsDuring the last five years, two new

insect pests have invaded the industry.One of these, the “white” sugarcaneaphid, is the most damaging aphid on

sugarcane world-wide. It is alsocapable of spread-ing yellow leafvirus, a diseasenew to sugarcanein Louisiana.Thus, IPM insugarcane willneed to continue toevolve andbecome more teaminterdisciplinary toaddress the newchallengespresented by theever-changingsituations con-fronted by farmersin Louisiana.

T. Eugene “Gene” Reagan, Professor,Department of Entomology, LSUAgCenter, Baton Rouge, La.

Table 1. A comparison of wireworm control versusno wireworm control on management of thesugarcane borer (SCB). Though soil pesticides aresometimes needed, there is always a chance that theimpact on non-target organisms will exacerbateproblems with the sugarcane borer.

Paired FieldsWireworm Control Non-Wireworm Control% Bored SCB Control % Bored SCB Control

Parish Field Pair Internodes Applications Internodes Applications

Lafayette 1 20.6 3 2 1Lafayette 2 6.1 3 1.6 0Lafayette 3 10.5 3 1.5 1Iberia 4 44.1* 0* 5 0Iberia 5 15.9 3 1.3 1Vermilion 6 9.5 2 3.9 1

Averages 17.8 2.33 2.6 0.67*Field not under consulting contract; additionally, there is some question thatthe grower may have used a rate slightly higher than recommended but stillwithin the label.


ew sugarcane varieties are thelifeblood of the Louisiana sugar indus-try. In fact, the high and the low pointsof the Louisiana sugar industry closelyparallel those of sugarcane varietydevelopment. The first sugarcanevarieties grown in Louisiana were offoreign origin. Introduced varieties weretypically renamed and included “Cre-ole,” from which Etienne De Bore firstgranulated sugar, “Otaheite,” and later“Louisiana Striped” and “LouisianaPurple.”

Later, sugarcane varieties wereimproved by producing sugarcaneseedlings through crossing. Crossinginvolves taking pollen from one varietyto fertilize seeds of another variety tocreate a new plant with desired charac-teristics from both parents. The fertilityof the sugarcane flower was firstestablished in 1858 at the HighlandsPlantation in Barbados. Not until 1889in Barbados (and soon thereafter inJava) were the first seedlings success-fully produced through crossing. In1890, seedcane from these first seed-lings developed in Barbados were grownin Louisiana at a research facility in

Audubon Park in New Orleans. Theterm seedcane refers to the fact thatsugarcane is planted as stalks rather thanseed.

In the 1920s, sugarcane diseasesdecimated the Louisiana sugar industry.The only way to overcome the diseaseproblem was to introduce new varieties.Through the U.S. Department ofAgriculture (USDA), new foreignsugarcane varieties, primarily the POJvarieties from Java, and seedlings wereimported and quarantined. In 1922, theLouisiana Agricultural ExperimentStation (LAES) received seed from theUSDA Sugarcane Station at Canal Point,Fla. After the USDA established aSugarcane Research Unit at Houma, La.,seed from Canal Point were sent there.Evaluation of varieties from bothforeign introductions and seedlingsources was initiated in 1924, throughthe cooperative efforts of the LAES, theUSDA and the American Sugar CaneLeague.

Developing New VarietiesNew sugarcane varieties begin with

the creation of new genetic combina-

tions through crossing. Because sugar-cane is a tropical plant, it rarely flowersunder natural conditions in Louisiana.From 1950 to 1953, LAES scientistsattempted to cross sugarcane at one ofLouisiana’s southernmost points, GrandIsle. After discovering that sugarcaneflowers according to a photoperiod (daylength) response, sugarcane crossingwas begun in Baton Rouge in 1954, withthe aid of photoperiod inductionfacilities on the LSU campus. In 1982,photoperiod, crossing and seedlingfacilities were constructed at the LSUAgCenter’s St. Gabriel ResearchStation, where sugarcane breedingcontinues today. The American SugarCane League was helpful in establishingthese new facilities. The AgCenter’ssugarcane breeding program is the onlyone in the world that relies solely oncontrolled photoperiod induction toproduce flowers for crossing.

Kenneth Gravois, Resident Director, SugarResearch Station and St. Gabriel Research Station,and Keith Bischoff, Assistant Professor, SugarResearch Station, St. Gabriel, La.

Kenneth Gravois and Keith Bischoff

N

Photo by John Wozniak At left is the crossing house and at right is the photoperiod inductionfacility at the LSU AgCenter’s Sugar Research Station at St. Gabriel, La.

New Sugarcane VarietiesNew Sugarcane Varieties

Pay Big Dividends


A

D


A All together there are 324 containers holding 150 different varieties of sugarcaneunder investigation at the Sugar Research Station. Photo by Mark Claesgens

B The breeding canes are rolled into the photoperiod houses and induced to flower.Photo by Mark Claesgens

C New varieties are allowed to flower naturally in the crossing houses to get initialinformation on their photoperiod response. Photo by Mark Claesgens

D Inside the crossing house. Photo by Mark Claesgens

E The plants are protected from each other with panes of clear plastic on three sides.Photo by John Wozniak

F After crossing, the sugarcane seed, called “fuzz,” is bagged to be dried and latergerminated for seedling production. Chris LaBorde is the research associate in chargeof crossing. Photo by John Wozniak


B C

E

F



The development of a new sugar-cane variety takes many years (Table 1).Crossing in the LSU AgCenter breedingprogram is done each fall. Seed pro-duced in the crossing program isgerminated the following January in thegreenhouse. Seedlings are potted intoindividual cells in a tray system inFebruary. In mid-April, the seedlings aretransplanted into the field with 16-inchspacing. The plantcane seedling crop isharvested, and selection is practiced thefollowing year in the first stubbleseedling crop.

First stubble refers to the first cropof stalks that develops from buds on thestubble remaining in the field afterharvest. Stalks of selections from the

single-stool seedling stage are planted inFirst Line Trials (single-row, 6-footplots). The following year, selectionsfrom the First Line Trials are advancedto the Second Line Trials (single-row,16-foot plots). Experimental varietiesselected in the first stubble crop of theSecond Line Trials are assigned perma-nent variety designations.

Variety assignments are planted atthree on-station locations (St. Gabriel,the LSU AgCenter’s Iberia ResearchStation and the USDA’s Ardoyne Farm)as Nursery Trials. The following yearthe variety assignments are replanted atfive off-station locations on cooperatingfarms as either an Infield Trial or aNursery Trial. The next year, these

Year Stage Description 2001 Crossing Seed is produced in the fall

from photoperiod-inducedflowering.

2002 Seedling - Plantcane Crop Seed is germinated in Januaryin the greenhouse. Seedlingsare potted into individual cellsin a tray system in February.In mid-April, seedlings aretransplanted into the fieldwith 16-inch spacing.

2003 Seedling - First Stubble Crop Selections advanced.

2004 First Line Trials Single-row, 6-foot plots.

2005 Second Line Trials - Plantcane Single-row, 16-foot plots.

2006 Second Line Trials - Single-row, 16-foot plots.First Stubble (Assignments)

2007 On-station nurseries Three locations; 2 replica-tions; single-row, 16-foot plots.

2008 Infield and off-station nurseries Five locations; 2 replications;single-row, 20-foot plots(Nursery) or 2-row, 24-footplots (Infield)

2009 Seedcane introduced to Outfield Seedcane increased.Testing; seedcane introduced tofour Primary Increase Stations

2010 Planted in Outfield Variety Trials; 10 locations; 3 replications;seedcane increased on four Primary three-row, 32-foot plotsStations

2011 Outfield Variety Trials - Plantcane 10 locations; 3 replications;harvested; seedcane increased on three-row, 32-foot plotsfour Primary Stations

2012 Outfield Variety Trials - First stubble 10 locations; 3 replications;harvested; seedcane increased on 44 three- row, 32-foot plotsSecondary Stations

2013 Outfield Variety Trials - Second 10 locations; 3 replications;stubble harvested; seedcane three-row, 32-foot plotsincreased on 44 Secondary Stations

2014 Variety Release-Seedcane from 44 Industry-wideSecondary Stations sold to farmers

Table 1. The time line involved in the release of a newsugarcane variety.

varieties are introduced as seedcaneincreases to the Outfield Testinglocations and Primary Seed IncreaseStations. Outfield Testing is conductedcooperatively by the LSU AgCenter, theUSDA’s Sugarcane Research Unit atHouma and the American Sugar CaneLeague. After the initial seedcaneincrease at each Outfield location,varieties are planted in a replicatedvariety trial.

As long as the variety resultsremain promising, the variety staysin the program and is replanted in theOutfield Testing program. After data arecollected on at least one second stubblecrop of Outfield Testing, a new varietymay be released to the industry. Releaseoccurs 13 years after the initial cross.Seedcane increase for a potential varietyrelease to farmers is done on Primaryand Secondary Seed Increase Stationsand is the sole responsibility of theAmerican Sugar Cane League. The yearafter a new variety is released, certifiedseedcane is available from a commercialseedcane company.

LCP 85-384 VarietyA hallmark of the LSU AgCenter’s

sugarcane breeding program was theselection of LCP 85-384 and its releasein 1993. The LCP 85-384 story began inthe mid-1960s with the establishment ofthe basic breeding program at theUSDA’s Houma unit. The objectiveof the basic breeding program is tointroduce new genes from differentspecies that contribute to diseaseresistance, stubbling ability and coldtolerance along with higher yieldpotential.

The prefix “LCP” indicates theorigins of the variety. The cross of LCP85-384 was made at Canal Point, Fla.,thus “CP.” The variety was selected bypersonnel from the AgCenter’s Louisi-ana “L” sugarcane breeding program.The parents of LCP 85-384 are CP 77-



310 and CP 77-407. The male parent,CP 77-407, was developed in the USDAbasic breeding program, which has as itsobjective to broaden the genetic base ofnew sugarcane varieties.

LCP 85-384 has provided a 20percent to 25 percent yield increase overvarieties grown at the time of its release.In addition to its unsurpassed yieldpotential, the variety offers excellentstubbling ability and cold tolerance.These characteristics make it possible togrow more crops from a single planting.

Because of Louisiana’s temperateclimate, the sugarcane crop mustoverwinter for two to three months.Before LCP 85-384, the typical rotationfor sugarcane grown in Louisiana was aplantcane crop and two stubble crops. Inyears with mild winters, some thirdstubble crops could be grown. Thetypical rotation with LCP 85-384 is aplantcane crop plus three to four stubblecrops. With depressed prices for sugar,the increased production from LCP 85-384 and the additional crops grown fromthe initial planting have kept Louisianafarmers in business.

capacity after many years of beingunderused. The annual impact of LCP85-384 has been to infuse at least $100million into the Louisiana economythrough the sugar industry.

Dependency on one variety is risky,however. If LCP 85-384 were to becomesusceptible to a disease, for example,then a high percentage of Louisiana’scane could be affected. To prevent this,Louisiana’s sugarcane breeding programhas been expanded to facilitate newvariety development. Both the LSUAgCenter and the Louisiana sugarindustry through the American SugarCane League have contributed resourcesfor this expansion.

Another advantage of LCP 85-384is that it is a good parent as well asproducer. The AgCenter’s breedingprogram is developing new varietiesderived from crosses involving LCP 85-384 as a parent. The goal is creation ofvarieties with as high or even higheryield potential along with disease andinsect resistance.

New sugarcane varieties have paidand will continue to pay big dividendsfor Louisiana sugarcane farmers andprocessors.

HarvestingHarvesting in Louisiana has been

done with whole stalk harvesters sincethe 1940s. The sugarcane breedingprogram emphasized harvesting charac-teristics such as erectness and non-brittleness in the selection and releaseof new varieties. The varieties CP 52-68and CP 65-357 were developed foradaptability to whole stalk harvestingsystems.

LCP 85-384, on the other hand,helped usher in the age of combineharvesting in Louisiana. Because of thevariety’s high tonnage and lodgingcharacteristics, harvesting LCP 85-384with whole stalk harvesters is difficult.The combine harvesting system worksmore efficiently and has helped farmersrealize the potential of LCP 85-384.

The economic impact of LCP 85-384 has been tremendous. In 2001, itwas grown on 82 percent of Louisiana’ssugarcane acreage. The higher yieldsand larger number of stubble crops havehelped both the farm and the sugarfactory. Increased production has helpedincrease profits on all farming opera-tions. Sugar factories have realized full


Keith Bischoff, LSU AgCenter researcher, has been involved withthe development of LCP 85-384 since the beginning. The first

cross was made in 1978, and it was released in 1993. The newvariety increased sugar yields by 20 percent to 25 percent.


he production of sugarcane inLouisiana is much more complex, froma farm management perspective, thanthe production of other major crops suchas cotton, soybeans or rice. Althoughsome production decisions are similar,others are unique to sugarcane in partbecause of the perennial nature of thecrop. Unlike annual crops such as cottonor soybeans, which are planted fromseed and harvested each year, sugarcaneis planted vegetatively and harvestedover several years. Sugarcane growerspurchase disease-free seedcane forplanting. This seedcane acreage is thenexpanded (harvested and replanted) overa couple of years until it is then plantedin production fields to be harvested asmillable sugarcane. A typical sugarcanefield in Louisiana may be harvested overthree to five or more years before it isreplanted. Growers must decide whensugarcane fields should be plowed outand replanted.

All of these various decisionsdirectly affect the net returns of grow-ers. Economic research on sugarcaneproduction conducted by the LouisianaAgricultural Experiment Station (LAES)analyzes the impact of these variousproduction decisions on the costs ofproducing sugarcane in Louisiana aswell as the market returns received bysugarcane growers. Following are threeexamples of recent economic researchby the LAES that help sugarcanegrowers make sound farm managementdecisions for maximum economicreturn.

Production costsGood management is a crucial

factor in the success of any business,and the business of farming is noexception. For sugarcane farming tobe successful and economically viable,sugarcane growers must know whatimpact specific farm management andproduction decisions will have onproduction costs. To provide informa-tion to sugarcane growers that can aidfarm management and productiondecisions, the LAES annually publishesdetailed estimates of the projected costsand returns of producing sugarcane inLouisiana.

Annual projections of the costsand returns associated with producingsugarcane in Louisiana are estimated fortenant-operators producing sugarcane intwo budget formats. One format is asummary of costs and returns for aparticular phase of sugarcane produc-tion. This format presents costs by broadcategories such has fertilizer, herbicides,insecticides, labor, fuel and repairs. Theother format presents a detailed list ofthe field operations and equipment sizealong with the associated costs fortractors, other machinery and inputmaterials. Specific phases of thesugarcane production cycle for whichproduction costs are estimated includefallow field operations, seedbed prepara-tion, planting cultured and propagatedseedcane, plantcane and stubble cropfield operations, and harvest operations.

Additional information provided inthe annual production costs and returnsreports includes whole-farm income andexpense estimates as well as breakevenprices of raw sugar to cover totalspecified production costs at various

yield levels. Together these budgetprojections provide the detailed infor-mation growers need to adjust thepublished estimated budgets to theirspecific farm operations. In addition,this report contains detailed costestimates for an extensive list ofequipment and operating inputs thatmay be used to modify budgets con-tained in the report or construct newenterprise budgets.

This report, entitled “ProjectedCosts and Returns—Sugarcane,” whichis published each January, is availablethrough parish extension offices or on-line through the LSU AgCenter’sDepartment of Agricultural Economicsand Agribusiness Web site—www.agecon.lsu.edu.

Crop cycle lengthThe widespread adoption of the

high-yielding sugarcane variety LCP 85-384 over the past few years has resultedin two significant changes in theLouisiana sugarcane industry. Plantcharacteristics of this variety make itsuitable for combine harvesting andhelped to promote the conversion fromwholestalk harvesting to combineharvesting. Second, LCP 85-384 is anexcellent stubbling variety, resulting inthe expansion of standard sugarcanecrop cycles beyond harvest of secondstubble. As a result, Louisiana sugarcanegrowers are trying to determine theoptimal number of years to keep asugarcane field in production beforereplanting and starting a new crop cycle.Because of soil type differences andother factors that affect yield andproduction costs, this decision must bemade annually on a field-by-field basis.

Michael E. Salassi, Associate Professor,Department of Agricultural Economics, LSUAgCenter, Baton Rouge, La.

T


This is mechanical planting of whole stalks.

Michael E. Salassi

Economic Analyses HelpSugarcane Growers’ Bottom Line

Economic Analyses HelpSugarcane Growers’ Bottom Line


Research is under way to addressthis issue and provide sugarcanegrowers with information to use todetermine the optimal number of stubblecrops to keep in production. The rule touse in making this determination is:keep a stubble crop in production if theestimated net returns from the harvest ofthat crop increases the average returnper acre over the entire crop cycle.Otherwise plow out the stubble and starta new crop cycle.

Outfield trial yield data over the1996-2000 period for major sugarcanevarieties produced in Louisiana arebeing used to determine the optimalcrop cycle length which would maxi-mize the net present value of producerreturns. Cane yield and sugar per tondata for plantcane through third stubbleare used to estimate the annualized netreturn of sugarcane production throughharvest of second and third stubblecrops and to determine the breakevenlevel of fourth stubble yields that wouldeconomically justify production andharvest.

Analysis of yield and net return datafor the varieties CP 70-321, LCP 85-384and HoCP 85-845 indicated thatminimum yield levels necessary to keepolder stubble in production for harvestdepend directly upon the yields of theprior crop cycle phases and differsignificantly across varieties. Estimatedbreakeven yields for major varieties ofsugarcane produced in Louisiana willprovide growers with benchmarks theycan use in determining whether aspecific field should be kept in produc-tion or plowed out and replanted.

Some farm management decisionsassociated with sugarcane production

are made infrequently, but yet have asignificant impact on farm productioncosts and returns. One such decision isrelated to precision grading of land.Precision grading is an improvementthat increases the value of agriculturalland. The costs of precision gradingrepresent a long-term investment in theproductive capacity and profitability ofcropland.

Grading landThe main purpose of grading land is

to level the field’s surface and grade itto a specific slope that will improvedrainage of water from the field.Improved drainage can reduce thenumber of drainage ditches required.Land used for drainage ditches can bereturned to sugarcane production,thereby increasing sugarcane productionand gross returns per acre.

Before investing in precisiongrading, a couple of key cost consider-ations should be addressed. The firstinvolves whether the producer shouldpurchase the laser-leveling and dirt-moving equipment and do the workhimself or hire the work out to someoneelse on a custom-hired basis. The secondcost consideration is determining howmany years of sugarcane production willbe required to recover the investment inprecision grading costs.

The costs associated with precisiongrading sugarcane fields in Louisianawere estimated for the situation in whichthe producer would purchase the laserleveling equipment and perform thework with on-farm labor. These costestimates were then compared withcustom rate charges for land grading.Costs of precision grading sugarcane

fields on a per acre basis were anestimated $84 per acre for operatingcosts, including fuel, repairs and labor.Fixed costs were an estimated $70 peracre, resulting in an estimate of totalcosts of $154 per acre to move 300cubic yards of dirt.

On a cost per unit of dirt movedbasis, this total cost estimated translatesto a total cost of $0.51 per cubic yard ofdirt moved. Operating costs wereestimated to be $0.28 per cubic yard,and fixed costs to be $0.23 per cubicyard. With custom grading charges inthe range of $0.80 to $0.90 per cubicyard, a sugarcane grower planning toprecision grade large tracts of acreageover a period of several years could savesubstantial costs by performing the workwith on-farm labor. It was estimated thatthe initial investment in precisiongrading costs could be recovered in fourto six years from the increased sugar-cane production per acre.

Determination of whether toprecision grade fields with ownedequipment and on-farm labor or hiredout on a custom basis will depend onthe total acreage to be graded and laboravailability. For smaller land tracts ofjust a few hundred acres, it may be moreeconomical to hire the grading work ona custom basis. However, if severalhundred or more acres are planned toprecision grading over several years,purchasing the grading equipment andperforming the work with on-farm laboris probably the most economicaldecision. Results of this study providedgrowers with evidence that precisiongrading of sugarcane fields can be aneconomical way to increase returnsfrom sugarcane production.

This is what planting of whole stalks looked like in 1947.From the LSU AgCenter archive.


esearch into sugar processing hastaken place at Audubon Sugar Institute(ASI) for more than 100 years, helpingthe Louisiana industry improve itsefficiency and lower its cost of produc-tion. There have been many changes atAudubon Sugar Institute, but in the lastfew years, both the sugar industry andthe research environment have changedsignificantly. It is, therefore, appropriateto look at the role of the institute bothnow and in the future.

Institute’s RoleThe staff and faculty have adopted a

new mission statement and someassociated goals that have been acceptedby the LSU AgCenter and by theLouisiana processors. The mission is to

Peter Rein, Professor and Head, Audubon SugarInstitute, LSU AgCenter, Baton Rouge, La.

Lenn Goudeau, research associate at the Audubon Sugar Institute, is in charge of sugar boiling at the factoryon the LSU campus, which includes pilot plant equipment to simulate all of the operations of a sugar mill.

foster a center of excellence for appliedand original sugar research, whichexceeds the expectations of our stake-holders in Louisiana and the interna-tional sugar industry, through innovativeresearch, technology transfer andeducation. The goals are these:

Enhance the productivity andprofitability of the Louisianasugar and sugar process-relatedindustries.Improve the practice of sugarmanufacture through educationand technology transfer.Conduct research toward a diver-sified sugar process industry.Attract, retain and develop aworld-class staff to serve ourstakeholders.Encourage use of low environ-mental impact technologies insugar processing.

Working with MillsIn general, there is a real desire on

the part of the 17 mills in Louisiana tohave a fruitful association with ASI. Theissues important in creating and main-taining an effective organization havebeen identified, and changes are beingintroduced to ensure that the require-ments of all stakeholders are being met.It is clear that the millers would like tosee more of ASI staff at the mills, moreclosely involved with what is going onin the mills and would like to see ASIpeople involved in practical work ofgreater direct relevance to the mills.With an emphasis on customer orienta-tion, research and extension need to bemore closely combined.

There also seems to be a place forASI to act as a catalyst in encouraginga freer flow of information with and

between mills and byactively seeking topromote technologytransfer. The Web site(www.lsuagcenter.com/audubon) will be usedmore comprehensively todisseminate information.It is envisioned that itwill be used for commu-nicating performanceresults to mills, forexchanging informationof a technical nature, forpromoting technologytransfer to the mills,and as a source ofabstracts and othertechnical information.

It seems likely thatadditional support maybe obtained from theFlorida mills and perhapsfrom other mills orindustries. If sufficientfunding is not availablefrom the sugar industryin Louisiana, it isreasonable to pursue thisroute, which also helps tokeep the institute up todate internationally.

R


Audubon Sugar Institute:Addressing Processing Research Needs

Peter Rein


Core CompetenciesResearch areas in which Audubon

staff are particularly skilled and experi-enced represent core competencies.They are:

ClarificationExtraction by diffusionMicrobiology of sugar processingMembrane separation processesEvaporation, and scaling inparticularBatch pan boilingContinuous pan boilingCrystallization fundamentalsChromatographic separationtechniquesFermentation of sugar-relatedfeedstocks

Faculty members have adjunctappointments in the departments ofbiological engineering, chemicalengineering, food science and microbi-ology. Post-graduate students in thesedepartments are supervised by facultymembers. There is room for morecollaboration with the other LSUdisciplines where relevant.

Advisory Research BoardControl over the way research funds

are spent can be achieved by inviting theresearch funders to sit on an AdvisoryResearch Board to approve an annualresearch program. A steering committee

composed of a representative of each ofthe Louisiana mills has been meeting asthe forerunner of this board. This groupidentified the following areas ofresearch: green cane processing (factoryaspects), cane payment systems, effectof cane wash systems and impurities onprocessing and equipment, reducingfactory losses through better measure-ment and control, evaporator scaling andtube cleaning, color removal, effectiveuse of instrumentation and automation,reducing production costs, evaluation ofequipment and boiler emissions.

These are distillation columns used inresearch at the sugar factory, which housesa wide variety of processing equipment withlaboratories on the second and third floors.

Education and TrainingASI is positioning itself as the

provider of suitable education andtraining for the sugar industry. ASI hasoffered a number of short courses overthe years and continues to do so. A listof options is on the ASI Web site.

The skills levels in Louisiana millsneed to be deepened. Two new coursesin sugar processing technology andsugar factory design have been ap-proved, as well as the option forstudents in the College of Engineeringto minor in sugar engineering. A timeduring the crushing season at a localsugar mill as a period of internship canbe incorporated, if desired. Using thesecourses and a sugar-oriented researchprogram, it also is possible to offer amaster’s program in engineering.

The reinstatement of courses at ASIwill be beneficial for the research effort,because teaching always complementsand stimulates research. Teaching bringsus closer to our target markets so webecome more useful to our clients. Inaddition, more graduate students wouldbe available for projects.

Clear FocusThe Audubon Sugar Institute has

a clear focus, and the mechanism forsetting funding levels and researchpriorities through an Advisory ResearchBoard is being put into place. This willensure that the institute is deliveringvalue for the research investment. ASIwill be giving more attention to the wayit handles its outreach program, and it isre-introducing teaching in undergradu-ate and graduate programs to augmentresearch efforts and keep ASI in touchwith its stakeholders.

ASI has several advantages in theglobal sugar research arena. It has thebacking of a major university and awell-established brand name as a sugarinstitute of renown. It is not tied only toone country’s sugar industry, but has thepotential to operate as an internationalinstitute to the benefit of the LSUAgCenter and the sugar industry. It hasgood pilot plant and laboratory facilitiesand is well placed in Louisiana. Torealize these advantages, the infrastruc-ture and buildings are being upgraded.It should be possible to take Audubonback to the position it previouslyoccupied as the premier internationalsugar institute.

FacilitiesASI had a small sugar mill on

campus that is no longer operational,in part because of the environmentalimplications of running a sugar factoryin the middle of a busy universitycampus. The option of moving it eitherto the research station at St. Gabriel orto a nearby mill is being considered.Relocating it provides the option ofupdating its archaic design and provid-ing a modern facility capable ofhandling billeted cane. It would setASI apart as having a unique facility,enabling it to do work no other institutecan consider. A feasibility study hasbeen started, and the process is underway to secure funding.

Research is under way on removinginorganic impurities and direct productionof white sugar in one step, which will be atremendous economic boost for theLouisiana sugar industry.


In 1887, a group of sugarcane growers known as theLouisiana Planters Association set up a research facility inAudubon Park in New Orleans so they could learn more aboutthe granulation process. This was the beginning of the AudubonSugar Institute. C.W. Stubbs, a professor of agriculture, becamethe first director of the station. A classroom building in the LSUQuadrangle is named in his honor.

In 1890, a mill was started at the Audubon station, and, in1891, the Audubon Sugar School was established and the firstsugar engineering course was offered. The course grew into afive-year program, and a research component was added. In1916, the school’s director, Charles Coates, a professor ofchemistry, published an article titled “A Twenty Five YearExperiment in Chemical Engineering Education: The AudubonSugar School.” Another building in the LSU Quadrangle is namedfor Coates.

In 1925, the school was transferred to the Baton Rougecampus, and a sugar factory was built. This factory had a crushingcapacity of 15 tons of cane per hour, or 360 tons per day, andcrushed cane continuously during the Louisiana sugar season. Inthe early days cane fields bordered the edge of the campuswhere the factory was located. The raw sugar product and thebyproducts, molasses and bagasse, were shipped to commercialcustomers. Generations of sugar technologists trained at thisfacility, and LSU provided the leaders for the sugar industriesaround the world.

After about 40 years of operation, the Audubon factoryceased grinding cane on a continuous basis. The milling tandem

remains, but most of the factory equipment was removed. Theinstitute now houses a wide variety of processing equipment inthe factory building, with research laboratories on the secondand third floors. The ground floor area is extensive, with pilotplant equipment to simulate all of the operations of a sugar millor an alcohol plant.

Succeeding Coates, the respective directors through 1976were Paul M. Horton, Arthur G. Keller and John J. Seip. In 1977,the school, which had been an integral part of the Departmentof Chemical Engineering, became an independent department,with J.A. Polack, professor of chemical engineering, as director.The name was changed to Audubon Sugar Institute. In 1986, theinstitute was transferred to the LSU Agricultural Center. WillemH. Kampen, associate professor, followed F.A. Martin, professorof agronomy, as head of Audubon Sugar Institute. In July 2000,Peter Rein, formerly technical director of Tongaat-Hulett Sugarin South Africa, took over as professor and head.

The Audubon Sugar Institute has a long history and a proudtradition and has educated many sugar technologists and sugarengineers. With the re-introduction of formal courses in sugarprocessing and sugar engineering, the Audubon Sugar Institutewill return to its previous status as a provider of university-approved training. This once more puts the institute in a uniqueposition as a center of excellence for teaching, research andextension. It is ideally located in the Louisiana sugar industry andpoised to regain its former stature.

Audubon Sugar Institute:

Peter Rein, Professor and Head, Audubon Sugar Institute, LSU AgCenter,Baton Rouge, La.

Poised to Continue Its Proud Tradition

A product made from Louisiana sugar that may helpreduce the incidence of poultry-borne food poisoning, as wellas help slow the emergence of drug-resistant pathogens, isunder investigation at the Audubon Sugar Institute.

A branched glucooligosaccharide, prepared by the fer-mentation of sugar, was found to be an efficient “prebiotic” orfunctional food. A prebiotic is a compound that when taken inthe diet favors the establishment of health-maintaining bacteriato the exclusion of harmful bacteria.

Oligosaccharides are already popular functional foodswith numerous applications as food additives in such productsas soft drinks and cookies. Glucooligosaccharides are widelysold as food supplements in Asia to help people with digestivedisorders. But they are not available in this country.

Current technology for the production ofglucooligosaccharides is complicated and costly, making it

Sugar Product May Substitute for Antibiotic in Animal Feedprohibitive to use them in animal feed. However, use of aunique strain of microorganism grown on sugar in the pres-ence of specific inhibitors results in the rapid production of agroup of glucooligosaccharides. The cost would be about onehundredth of what it is now and thus allow their use in animalfeed.

Use of these glucooligosaccarides in poultry feed willfavor the growth of healthy, Salmonella-free birds, withoutusing antibiotics. Less use of antibiotics helps reduce thedevelopment antibiotic-resistant bacteria.

The next step is working in cooperation with the U.S.Department of Agriculture to test this product on chickens.

Donal Day, Professor, Audubon Sugar Institute, LSU AgCenter, BatonRouge, La.


oil fertility and plant nutritionresearch are important components ofthe LSU AgCenter’s sugarcane researchefforts. With tight economic conditionsand increasing concern for the environ-ment, it is important that the nutritionalneeds of sugarcane be met withoutapplying excess nutrients. To meet thischallenge, the LSU AgCenter maintainsa rigorous program for examining thenutritional needs of the recommendedsugarcane varieties on the major soilgroups where sugarcane is grown.

Nitrogen FertilizerThe biggest fertilizer expense for

sugarcane is nitrogen (N). Becausesugarcane is a member of the grassfamily, it requires large amounts ofnitrogen to produce optimal yields.Nitrogen is provided by atmosphericnitrogen, soil nitrogen and the decompo-sition of soil organic matter. The largestsource of plant nitrogen, however, isthat of commercial inorganic nitrogen,which is usually applied to the sides ofsugarcane rows each spring that a cropis grown. Nitrogen can be supplied ineither dry or liquid form and is usuallycovered with soil after application.

The high yields obtained withsugarcane variety LCP 85-384 (20percent to 25 percent more than the nextbest variety) have raised questions aboutwhether this variety should receive thesame amount of nitrogen as otherrecommended sugarcane varieties. Someproducers apply more than the recom-mended N rate to LCP 85-384 because itproduces higher yields; others apply lessin an effort to reduce lodging, which cancause yield losses at harvest.

Yield Response to NitrogenTo answer the question of whether

variety LCP 85-384 should be fertilizedwith the same nitrogen rates as othersugarcane varieties, 11 years of research(five years for plant cane, four for first-stubble and one each for second- andthird-stubble cane) were conducted withLCP 85-384 on heavy-textured soil inthe Teche region of Louisiana. Eco-nomic analyses were based on a sugarprice of $0.19 per pound, nitrogen

Fertility ResearchHelps Optimize Sugarcane ProfitsWilliam Hallmark, Greg Williams, Lester Brown and Gert Hawkins

William Hallmark, Professor; Greg Williams and Lester Brown, Research Associates, Iberia ResearchStation, Jeanerette, La.; and Gert Hawkins, Research Associate, Sugar Research Station, St. Gabriel, La.

Research has shown that adding more than the recommended rate of nitrogen to LCP 85-384 actually reduced sugar yields. Here researchers are determining sugarcane yieldsfrom test plots.

At present, organic fertilizer is available only on a limited basis for commercial use, but aslandfills close because of environmental concerns and high costs, municipalities will needan alternative means of disposing their organic waste in a socially acceptable manner. Inthis sugarcane field we are evaluating the addition of lime-stabilized sewage sludge.

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fertilizer cost of $0.30 per pound of N,fertilizer application cost of $4 per acre,and the producer’s giving half of thecrop to the landlord and sugar mill.Our research shows it is important forsugarcane producers not to apply morethan the recommended N rate to LCP85-384 because doing so can reducesugar yields and net profits.

Results with plant cane show thatapplying 50 to 60 pounds of nitrogen peracre at four test sites resulted in as gooda sugar yield and producer profits aswhere the recommended rate (100 to120 pounds of nitrogen per acre) wasused. Applying more than the recom-mended rate (150 to 180 pounds ofnitrogen per acre) did not result inhigher sugar yields or producer profitsat four test sites, and actually reducedsugar yields by 630 pounds per acre($83 per acre) at one site. Consequently,our results indicate that sugarcaneproducers should avoid overfertilizingwith nitrogen and that they could reducenitrogen rates with plantcane.

Results with first-stubble caneshowed that applying 100 to 120 poundsof nitrogen per acre resulted in as high asugar yield and producer profits at twotest sites as where the recommended rate(140 to 160 pounds per acre) was used.At one site, overfertilizing with nitrogen(180 pounds per acre) resulted in lowersugar yields (420 pounds per acre) andreduced producer profits ($51 per acre).Our research indicates that LCP 85-384first-stubble cane should not be over-fertilized with nitrogen, and it mayrequire less nitrogen than is currentlyrecommended.

Results with second- and-third-stubble cane indicate that the recom-mended rate of 140 to 160 pounds peracre was consistent with optimal sugaryields and producer profits.

put out earlier, since there would be lesspotential for nitrogen loss caused byurea volatilization, nitrate leaching anddenitrification. To provide informationon the above, research was conducted onheavy-textured soil in the Teche regionof Louisiana.

Our work showed that placing dryurea nitrogen (120 pounds per acre eachyear) on row tops (of sugarcane rowswhere cane trash was burned theprevious fall) in early May resulted inequivalent sugar yields across four years(plantcane through third-stubble)compared to where dry urea was appliedto the sides of sugarcane rows (in earlyMay) and covered with soil.

Results further showed that apply-ing liquid nitrogen stabilized urea(containing calcium chloride and ureaseand nitrification inhibitors) in a 1-inchband in the row furrows betweensugarcane rows in late December toearly January resulted in as good a sugaryield across two years (plant and first-stubble cane) as where the same liquidurea N rates (60,100,140 and 180pounds per acre) were applied to thesides of the rows in early May andcovered with soil.

Organic Nitrogen FertilizerWhile inorganic nitrogen is the

overwhelming choice of nitrogenfertilizer applied by sugarcane produc-ers, organic fertilizer can be used on alimited basis to help meet the nutritionalrequirements of sugarcane. Sources oforganic nitrogen fertilizer includecomposted municipal and agriculturalwaste and municipal sewage sludge.Research at the Iberia Research Stationshows that these materials are safe andeffective sources of nutrients forsugarcane production. They are alsogood sources of organic matter, whichhelps improve soil structure and waterinfiltration and storage in soils. Sinceroot diseases of other crops have beenreduced with organic matter application,root disease in sugarcane (whichdepresses yield and can reduce thenumber of stubble crops) has thepotential to be reduced by organicfertilizer as well.

At present, organic fertilizer isavailable only on a limited basis forcommercial use, but as landfills closebecause of environmental concerns andhigh costs, municipalities will need analternative means of disposing theirorganic waste in a socially acceptablemanner. Making these wastes intoorganic fertilizer for use in agricultural

production would be a responsiblemeans of dealing with the solid wasteproblem.

Managing Combine ResidueAbout 85 percent of the sugarcane

acreage in Louisiana is harvested withcombine harvesters. Much of this caneis harvested green chopped, whichresults in a trash (residue) blanket on thesoil surface that can reduce sugar yieldsfrom 500 to 1,000 pounds per acre forthe following crop if it is not removed orburned. However, removing the residueblanket from the row tops and placing itin the furrow can cause cultivationproblems the following spring.

Many producers burn the trashblanket after harvest, resulting in airquality problems. Burning the sugarcaneresidue also results in loss of nitrogenand organic matter that could improve

Nitrogen Placementand Timing

Sugarcane in Louisiana is usuallyfertilized in the sides of the row in Aprilor May each year that a crop is grown.Some producers, however, have ex-pressed interest in applying nitrogenfertilizer on row tops. Also, littleresearch has been done to determinethe effect of using urease (slows the ratethat urea is converted to ammonium)and nitrification (reduces the rate thatammonium is converted to nitrate)inhibitors with urea nitrogen fertilizeron sugarcane yields. It is not knownwhether using urease and nitrificationinhibitors with urea would allow it to be



soil fertility and soil manageability ifthe trash blanket were not destroyed.

The sugarcane combine residueblanket is at present more of a liabilitythan an asset. Research in progress atthe Iberia Research Station seeks todetermine if spraying the combineresidue with nitrogen-stabilized urea(containing a urease and nitrificationinhibitor) can convert the trash blanketinto organic fertilizer, which couldincrease soil fertility and manageability.At this time, research results are toopremature to make a recommendation.

Fall FertilizerFertilizer is usually applied to

sugarcane in the spring for each yearthat the crop is grown. Research at theIberia Research Station, however,showed that applying a limited amountof inorganic fertilizer under cane at

planting (fall fertilizer) resulted inprofitable economic returns for heavy-textured soil. Our work showed that thefall fertilizer rate of 15 pounds ofnitrogen per acre, 60 pounds of phos-phate

per acre and 60 pounds of potas-

sium per acre resulted in increasedsugar yield and profits. Applying morethan 15 pounds of nitrogen per acre asfall fertilizer resulted in less sugar and anet loss in profits.

Potassium FertilizerResearch

Sugarcane requires large quantitiesof potassium. The recommended rate ofpotassium application to sugarcane inLouisiana is based on the crop year(plant or stubble cane), soil type and thelevel of exchangeable soil potassium.Potassium soil fertility research at theIberia Research Station is used to test

the validity of the potassium fertilizerrecommendations.

Potassium is usually applied aspotassium chloride, though some sugar-cane producers prefer to use potassiumsulfate. Our research is comparing theefficacy of the two potassium sourceson sugarcane yields. To date, our resultsindicate that potassium sulfate is notsuperior to potassium chloride ingrowing sugarcane.

Industrial ByproductsSources of byproducts for possible

use in growing sugarcane are byproductlime from sugar refineries, byproductgypsum from fertilizer producers,calcium silicate slag produced by steelprocessors and waste from aquacultureprocessors.

Our research shows that byproductlime and gypsum are very fine in textureand react quickly with soil to obtaintheir desired effect. Often these materi-als can be obtained for little more thanthe cost of shipping and are wisely usedby some sugarcane producers.

Calcium silicate slag is an effectiveliming material for reducing soil acidity.It provides silicon, an essential elementfor sugarcane growth and reproduction.Research at the Iberia Research Stationis evaluating the effects of calciumsilicate slag and fish emulsion insugarcane production.

Fertility Research SummaryLCP 85-384 plantcane and first-stubble cane should not beoverfertilized with nitrogen.Applying dry urea nitrogen fertil-izer in a band on row tops can bean effective way to fertilizesugarcane (where cane trash hadpreviously been burned).Liquid urea nitrogen (stabilized toprevent nitrogen loss) applied torow furrows in a narrow 1-inchband in the winter produced asgood a sugar yield as where Nwas applied to the sides of rowsin the spring.Applying a limited amount of fallfertilizer under cane at plantingcan increase sugar yields andproducer profits.Municipal and agricultural wastecan be safe and effective sourcesof organic matter and nutrientsfor producing sugarcane.Industrial byproducts offer acheap source of nutrients andliming materials.

Research under way at the LSU AgCenter’s Iberia Research Station seeks to determine ifspraying the combine residue with nitrogen-stabilized urea can convert the trash blanketinto organic fertilizer, which could increase soil fertility and manageability.


ouisiana is following a voluntaryapproach to managing potentialnonpoint-source pollution from agricul-ture. This strategy focuses on educationas the means to increase the adoption ofbest management practices (BMPs),which are those agricultural practicesdesigned to preserve, conserve and evenimprove the natural environment.

To measure the extent of adoptionof BMPs and factors that influence theiradoption, we conducted a survey ofLouisiana sugarcane producers in 1998.Our results are based on responses from223 producers, which is about 25percent of the sugarcane producers inthe state.

Rates of AdoptionThree different types of manage-

ment measures identified by Environ-mental Protection Agency (EPA)guidelines were included in the analysis:1) soil erosion and sediment control, 2)nutrient management and 3) pesticidemanagement. Within each measure,producers were asked about specificBMP alternatives. The managementmeasures and specific practices includedin the study are shown in Table 1. Thepractices range from those consideredeconomically feasible (and a typicalcultural practice) to practices consideredeconomically infeasible without costsharing. The list of practices was limitedto a maximum of four per managementmeasure because of statistical modelingconstraints.

Adoption rates for specifiedpractices were as follows:

Land leveling (S1) as a manage-ment practice was used by 75percent of the respondents.Seventy-two percent maintainedcrop residue (S3).Only 28 percent of the respon-dents used cover crops duringfallow (S2).Eighty-eight percent of therespondents used soil testing (N1)to determine fertilizer applications.Only 13 percent used alternativesources of nutrients (N3).Among the pesticide managementpractices, equipment calibration(P3) was done by 90 percent ofthe respondents.Eighty-five percent basedchemical applications on fieldscouting (P1).

Currently, the EPA considers aproducer compliant if he or she adoptedat least one BMP. The survey resultsindicate that Louisiana sugarcaneproducers would likely be in complianceunder this criterion, with more than 90percent of respondents adopting at leastone of the BMPs in each managementmeasure.

As environmental policy evolves,however, it is likely that higher compli-ance requirements will be imposed inthe future. A requirement of adopting atleast two BMPs per managementmeasure reduces the percentage incompliance slightly for sedimentcontrol and pesticide management, anda significant drop to 69 percent for thenutrient management measure.

Increasing the compliance require-ment to three BMPs per managementmeasure reduces compliance to abouthalf the producers in the sedimentcontrol and pesticide managementmeasures. Only 12 percent of producersadopted all three nutrient managementmeasures in the study.

Institutional VariablesInstitutional factors that may affect

the decision to adopt or not adopt BMPswere evaluated through several differentvariables. Awareness of legislationrelated to improving water quality wasassessed through two questions. Oneasked if the respondent was aware ofthe Coastal Nonpoint Pollution ControlProgram as specified in the CoastalZone Management Act, to which only44 percent responded positively, leavinga significant 56 percent unaware of theexistence of such legislation. Thesecond question aimed to determineawareness of the Clean Water Act; 65percent responded positively.

Respondents were asked if they hadever heard the term Best ManagementPractices; 65 percent indicated yes. Ofthose who had heard about Best Man-agement Practices, 78 percent indicatedthey believed that using Best Manage-ment Practices for sugarcane wouldimprove the quality of water whencompared to conventional productionpractices.

Survey results indicated thatrespondents met with ExtensionService personnel or attended educa-tional programs sponsored by ExtensionService an average of 3.38 times during1998. Respondents also indicated thatthey attended an average of 2.57 growermeetings in the same period.

Participation in cost-sharingprograms was an important institutionalfactor, with 63 percent of the respon-dents indicating they had participated incost-sharing programs for at least one ofthe practices that had offered that optionin the study area. The following prac-tices have had cost-sharing programs inthe past: land smoothing, precisionleveling and/or row arrangement; use ofdrop pipes or other grade stabilizationstructures to reduce erosion; use ofalternative sources of nutrients (manure,

Sugarcane Producersand Best Management Practices:

Steven A. Henning, Associate Professor,Department of Agricultural Economics andAgribusiness, LSU AgCenter, Baton Rouge, La.,and Hugo Cardona, former Graduate Assistantand now Professor, University of San Carlos inGuatemala

L

Attitudes and InfluencesSteven A. Henning and Hugo Cardona


Table 1. Selected Best Management Practices for Sugarcane

Pesticide Management Measures

P1 - Do you base chemical applications(insecticides, herbicides) on economicthresholds as determined by field scouting?

P2 - Do you use a containment facility formixing, loading and storage of farm chemi-cals?

P3 - Do you calibrate spray equipmentbefore each use?

P4 - Do you use any of the following forprecise application of chemicals: computersensing to control flow rates, radar speeddetermination, electrostatic applicators?

Nutrient Management Measures

N1 - Do you determine fertilizer applica-tions based on soil testing and expectedyields?

N2 - Do you use any of the followingfertilization practices: split application ofnutrients, banded application, slow-releasefertilizers?

N3 - Do you utilize alternate sources ofnutrients (manure, cover crops, sludge orany other organic matter)?

Erosion and Sediment ControlManagement Measures

S1 - Do you use any of the followingpractices to control runoff: land smoothing,precision leveling and/or row arrangement?

S2 - Do you occupy the fallow period witheither succession planted sugarcane or acover crop such as wheat, soybeans orothers?

S3 - Do you delay stubble breakout andmaintain crop residue (30% or more)through the winter months?

S4 - Do you use drop pipes or otherstructures to reduce bank erosion?

cover crops, sludge or any other organicmatter); and use of a containmentfacility for mixing, loading and storingfarm chemicals. Use of this variableinvolved aggregation to measure overallparticipation, under the assumption thatcost-sharing participation in at least onepractice may affect the adoption of otherpractices.

One variable in the assessmentmeasured environmental attitudes.Respondents were asked whether theybelieved that agriculture reduces thequality of water coming off farmland.Only 38 percent of the respondentsthought agriculture affects water quality.

Respondent CharacteristicsThe average response for self-

perception of risk was 4.17 on a scaleof 1 to 10, which indicated a tendencytoward risk aversion. Risk attitude, asmeasured by an investment venture,averaged 1.67, where 1 was the level formaximum risk aversion and 4 was thevalue of least risk aversion or more risktaking. About 30 percent of the respon-dents indicated that their firm debt levelwas more than 40 percent of the totalestimated value of farm business.

The average age of respondentswas 48 years. About 95 percent of therespondents were males. When askedwhether they planned to pass the farmoperation on to a member of theirfamily, 68 percent responded yes. Thepercentage of total gross householdincome from farming averaged 85percent.

The tenure status, as measured interms of the ratio of leased acreage overtotal farm size, indicated that 78 percentof the land was leased. Finally, 30percent of the respondents were orga-nized as individual operations, 20percent were organized in partnership,42 percent were family corporations and8 percent were non-family corporations.

Summary of ResultsMore than 90 percent of theresponding producers wereimplementing at least one bestmanagement practice for eachof the management measures.Results indicated that thedecision to adopt BMPs wassignificantly influenced by thenumber of times producers metwith Extension Service personneland the number of grower meet-ings attended in the previousyear.Producers who participated incost sharing were more likely toimplement management practicesfor which cost sharing did notexist.Risk of yield loss was not afactor in the adoption of theBMPs included in the study.Statistical analysis of the dataindicated a correlation within andbetween management measures.This supports the contention thateducation programs designed toincrease BMP adoption shouldconsider the benefits within andacross management measures tomaximize effectiveness.

Policy RecommendationsBased on the outcomes from this

study, the following general recommen-dations are made:

Offer more intensive educationalprograms to inform producers ofthe existence and implications offederal and state laws andregulations affecting productiondecisions.Develop educational programsthat focus on explaining howagriculture affects water qualityand how BMPs can have apositive impact on water quality.Develop educational programsthat explain when it is appropriateto adopt specific BMPs. Empha-size the costs and benefits ofimplementing BMPs.Continue to use the LouisianaCooperative Extension Serviceand grower organizations asprimary sources of educationalinformation.Investigate opportunities to costshare the adoption of BMPs,where feasible.Study the relationship betweencapital investment in BMPs andrate adoption. Focus on thefinancial appropriateness of suchinvestment.Study the relationship betweenleased land and implementationof BMPs—for example, theinfluence landowners can have onBMP adoption on leased land.


treatments, respectively. This was a loss of 7.8 percent, 5.7percent and 5.0 percent, respectively, of the amount of activeingredient applied. Thethree treatments weresignificantly different.Reducing the amount ofatrazine applied andbanding the herbicide onthe top of the cane rowsignificantly reduced theamount lost in the sur-face runoff.

Metribuzin was applied to the plots in March 18, 1994; May2, 1995; and May 8, 1997. The average annual metribuzin losseswere 1.10, 0.46 and 0.14ounces per acre (Table2) for the high, standardand low treatments, re-spectively. This was a lossof 3.5 percent, 2.9 per-cent and 1.2 percent, re-spectively, of the amountof active ingredient ap-plied. The three treat-ments were significantlydifferent. Reducing the amount of metribuzin applied and band-ing on the top of the cane row significantly reduced the amountlost in the surface runoff. The 24-inch band treatment producedsatisfactory weed control.

Major RainfallOn the morning of June 17, 1997, broadcast treatments of

atrazine and metribuzin were applied to designated plots forlayby weed control. Two hours after application, it startedraining. It rained 8.05 inches in 6 hours and 11.40 inches in 24hours. This was an unusual rainfall expected to occur only onceevery 75 years. It caused runoff from the area of more than 10inches. The total metribuzin lost in 44 days from the broadcasttreatment was 16.43 ounces per acre (51 percent of the appliedactive ingredient). The load from June 17 was 16.29 ounces peracre, which accounted for 99 percent of the total loss. Thelargest metribuzin concentration of 431 ppb was detected in thefirst runoff.

The total atrazine lost for the 44-day period was 1.26ounces per acre (4.5 percent of the applied active ingredient).The load from June 17 was 1.14 ounces per acre, whichaccounted for 88 percent of the total loss. The largest atrazineconcentration of 85 ppb was detected 21 days after application.The atrazine concentration detected in the first runoff (30 ppb)was 93 percent less than the metribuzin concentration the sameday. This enormous loss of metribuzin caused concentrations todiminish rapidly in the following events. Metribuzin concentra-tions were reduced to levels below the maximum concentrationlimit (MCL) of 200 ppb within 26 days after application, andatrazine concentrations were detected above its MCL of 3 ppbuntil 44 days after application.

Minimizing the levels of herbicides in surface water andgroundwater is of major concern nationally and within theagricultural community. Little work has been carried out oncorrelating application of herbicides used in sugarcane produc-tion with water quality impairment. Moreover, a LouisianaDepartment of Environmental Quality (DEQ) report from 1990indicated that most water bodies in Louisiana are impaired tosome degree. To address the need for more knowledge onsugarcane production and water quality, researchers at the LSUAgCenter initiated a study in 1992, as part of a DEQ sugarcanedemonstration project. The goal was to compare losses ofapplied herbicides (atrazine and metribuzin) in surface runoffwater on sugarcane fields under different management practices.The study consisted of three treatments over six growingseasons. The site chosen was at the LSU AgCenter’s St. GabrielResearch Station. A sump equipped with an electric pump wasinstalled on the low side of each of six research plots. Runoff wasmeasured with a water meter and sampled with an automaticwater sampler. Sample collection was triggered automaticallywhen runoff was detected.

Atrazine and metribuzin (sold as Sencor to farmers) are twoherbicides used in sugarcane production. Atrazine has been usedextensively for more than 40 years and is perhaps one of themost widely applied herbicides in the world. The lifetime healthadvisory for atrazine in drinking water is 3 parts per billion (ppb).Metribuzin is a commonly used herbicide with a lifetime healthadvisory level in drinking water of 200 ppb.

Three TreatmentsTo optimize the benefit from this work, the amounts of

herbicides applied to the plots were above and below thoserecommended for use as the accepted cultural practice forsugarcane in Louisiana. The high management treatment con-sisted of herbicides applied full broadcast at a rate 1.8 pounds peracre for atrazine and 2.0 pounds per acre for metribuzin. Thestandard management treatment consisted of herbicides appliedin a 36-inch band over the row at a rate 0.9 pound per acre foratrazine and 1.0 pound per acre for metribuzin. This is thecultural practice used by the Louisiana sugarcane industry. Thelow management treatment consisted of herbicides applied in a24-inch band over the row at a rate 0.6 pound per acre foratrazine and 0.7 pound for acre for metribuzin. For laybytreatments, herbicides were applied full broadcast at a rate 1.8pounds per acre for atrazine and 2.0 pounds per acre formetribuzin.

Average RainfallFrom 1994 to 1999, the average annual rainfall was 57.07

inches, which was close to the normal of 56.87 inches. Theannual rainfall ranged from a high of 70.48 inches in 1997, to a lowof 46.98 in 1999. The average annual surface runoff was 22.08,21.98 and 20.47 inches for the high, standard and low treat-ments, respectively.

Atrazine was applied to the plots on Jan. 6, 1994, and Dec.20, 1994. The average annual atrazine losses were 2.24, 0.82 and0.48 ounces per acre (Table 1) for the high, standard and low

Herbicide Losses in Surface Runoff

Table 2. Annual MetribuzinLoss (oz./acre)Year Treatment

High Standard Low

1994 0.09 0.05 0.031995 2.15 1.24 0.331996 1.05 0.10 0.07

Avg. 1.10 0.46 0.14

Table 1. Annual Atrazine Loss(oz./acre)Year Treatment

High Standard Low

1994 3.56 1.32 0.761995 0.92 0.33 0.20

Avg. 2.24 0.82 0.48



The 75-year return period storm that occurred withinhours after pesticide application had the timing and high runoffvolumes for major surface runoff. Since both atrazine andmetribuzin are poorly bound to soils, their potential loss insurface runoff is high.

SummaryThe atrazine losses were significantly different among treat-

ments. The atrazine losses from the broadcast method used inthe high treatment were 273 percent higher than for the 36-inchband used in the standard treatment. The herbicide fallingbetween the rows from the broadcast method washed off withthe surface runoff. Applying atrazine in 24-inch bands (lowmanagement treatment) reduced atrazine losses by 58 percentcompared to the 36-inch bands (standard managementpractice).

The metribuzin losses were significantly different amongtreatments. The metribuzin losses from the broadcast method(high management treatment) were 239 percent higher than forthe 36-inch bands (standard management treatment). The 24-inch bands used in the low management treatment reducedmetribuzin losses by 30 percent from the 36-inch bands.

Atrazine is less vulnerable than metribuzin to losses in highvolume runoff that occurs shortly after application. Althoughatrazine concentrations (30 ppb) in the 75-year return periodstorm were high, its low water solubility kept levels far below the431 ppb for metribuzin. The atrazine loss from the broadcastlayby treatment was 92 percent less than for metribuzin.

ConclusionsSugarcane growers have adopted the management practice

of spraying herbicide in 36-inch bands, which reduces herbicideloss by 87 percent from the broadcast method. Growers havealso started using metribuzin instead of atrazine. The concentra-tions of metribuzin in runoff water averaged 40 ppb, which was80 percent less than the 200 ppb MCL. Use of metribuzincontrols weeds and keeps the herbicide loss in runoff waterwithin U.S. Environmental Protection Agency (EPA) standards.

Richard Bengtson, Professor, Department of Biological and AgriculturalEngineering, LSU AgCenter, Baton Rouge, La., and Magdi Selim,Professor, Department of Agronomy, LSU AgCenter, Baton Rouge, La.

Louisiana SugarcaneProduction Areas

Sugarcane sweetens the Louisiana economy with about

a $2 billion contribution each year. That’s the result

of the efforts of about 750 producers in 23 parishes

(in blue) growing sugarcane on more than 450,000

acres. There are 17 sugar mills in Louisiana and two

refineries—one in Gramercy and the other in Chalmette.

Louisiana produces about 16 percent of the total sugar grown

in the United States (includes both beet and sugarcane sugar).


he ability of farmers to burnsugarcane is a significant economicfactor for the state’s sugarcane industry.Burning of sugarcane before harvesteliminates from 30 percent to 50 percentof the leafy trash (residue), whichconstitutes from 20 percent to 25percent of the total weight of the plant.For example, for a yield of 50 tons ofsugarcane per acre, 10 to 15 tons ofresidue must be removed before milling.Controlled agricultural burning allowsmore efficient sugarcane harvesting inthe field and improves sugar quality andrecovery in the factory. The residuecontributes nothing to the productionof sugar and has little or no economicvalue. The remainder of the plant con-sists of stalks from which the sugar iscrystallized from the extracted juice inprocessing. Harvesting burned sugar-cane results in less soil being broughtto the factory, reduces fuel consumptionbecause less material is transported tothe factory and uses less water in wash-ing the crop before milling. Reducingtransport within the field lessens soilcompaction. Currently, there is no pro-fitable or effective way to deal with thislarge volume of residue by mechanicalmeans either in the field or at thefactory.

Louisiana is not the only state, noris sugar production the only industry,facing the challenges posed by burningas an agricultural management tool.Every industry that uses burningrecognizes that a cost-effective mecha-nism for reducing or eliminating openfield burning is a high priority researchtopic. Further, because of current lowdomestic sugar prices, the farmer wouldbe hard-pressed to survive withoutburning to reduce production costs andimprove quality of the product deliveredto the factory.

Benjamin L. Legendre, Extension SugarcaneSpecialist, LSU AgCenter, Baton Rouge, La.

Prescribed Burns

T Recently, agricultural burningpolicy recommendations were preparedby the U.S. Department of Agriculture(USDA) Agricultural Air Quality TaskForce that would help farmers imple-ment provisions of the Clean Air Actwhile retaining the valid use of fire as amanagement tool. Task force membersincluded representation from agricul-tural producers, air quality researchers,agricultural industry representatives,medical researchers and state air qualityand USDA staff.

The policy addresses two goals:(1) to allow the use of fire as an accept-

ed management practice, consistentwith good science, to maintainagricultural production on agricul-tural land, and

(2) to protect public health and welfareby mitigating the effects of airpollution emissions on air qualityand visibility.In 2000, the Environmental Protec-

tion Agency (EPA) conducted threepublic meetings including one in NewIberia, La. The EPA has also solicitedwritten comments to help in the devel-opment of policies to address the airquality effects of agricultural burningand the use of USDA’s incentive-basedprograms in meeting ReasonablyAvailable Control Measures (RACM)and Best Available Control Measures(BACM) requirements.

Until proven technology allowseconomically efficient harvestingwithout burning, it is critical for canegrowers and processors to do the bestjob possible of managing smoke andash. Smoke and ash management can bedefined as conducting a prescribed burnunder recommended weather conditionsusing burning techniques that lessen theimpact on the environment and publichealth and welfare.

The Louisiana sugarcane industryhas been proactive in its efforts to helpthis situation by developing the Certi-fied Prescribed Burn Manager Program,which is administered by the Louisiana

Department of Agriculture and Forestry(LDAF). The LDAF, the AmericanSugar Cane League (ASCL) and theLSU AgCenter developed a trainingcurriculum titled, “Louisiana SmokeManagement Guidelines for SugarcaneHarvesting.” Although this training wasvoluntary, 1,382 cane farmers and theiremployees attended the sessions, whichwere held at various locations in thesugarcane-growing region during thesummer of 2000, with a makeup sessionin August of 2001. It seems that theCertified Prescribed Burn ManagerProgram worked exceptionally wellbecause there were significantly fewercomplaints received by the LDAF andthe ASCL during the 2000-2001 harvestthan in previous years.

The LSU AgCenter, in cooperationwith the USDA’s Agricultural ResearchService, has taken a proactive attitudetoward eliminating the need for orminimizing the effect of cane burningby initiating research on viable, eco-nomically feasible alternatives toagricultural burning to include value-added products from the cane crop’sresidue. Even though not specificallyrelated to air quality, an effective trashmanagement program that uses theresidue over the winter and spring toreduce runoff while minimizing theimpact of the residue on the yield of thesubsequent year’s crop would eliminatethe need to burn.

Demonstrating the potentialbenefits of effectively managing theresidue on the crop and the environmentalso may result in a higher percentage ofthe crop being harvested green by thecane combine. Other research initiativeshave shown that the residue left on thefield following green cane harvestingmay help suppress weeds and offer somefreeze protection during the winter.However, results also indicate a signifi-cant loss of sugarcane yield in thesubsequent stubble (ratoon) crop,especially following cold, wet winters.

Prescribed BurnsHelp the Sugarcane Industry

and Reduce Smoke and Ash ProblemsBenjamin L. Legendre


Additional studies haveindicated that leaving thisresidue on the field can resultin a higher population ofoverwintering sugarcaneborers, the No. 1 insect pest ofLouisiana sugarcane, as well asincrease the chances of damagefrom the sugarcane beetle,further increasing the probabil-ity of loss of yield in thesubsequent ratoon crop.Burning is the most cost-effective way of removing thisresidue following green caneharvesting. However, researchis under way to determine waysto speed up the decompositionof the residue using biologicalagents and sugar solutions,including molasses, whichcould reduce the need to burnthe residue.

Long-range plans are todevelop new sugarcanevarieties that shed their leavesbefore harvest. However, thisdoes little to eliminate theproblems associated with theresidue following green caneharvesting. In recent years,manufacturers of sugarcaneharvesters have devotedconsiderable resources in thedevelopment of a moreefficient green cane combinesystem for the domestic sugarindustry. However, this againdoes not answer the questionof what to do with the residueafter harvesting.

In summary, the goal ofresearch is to provide soundscientific basis for decision-making in keeping with therecommendations of theAgricultural Air Quality TaskForce. The goal of reducing airpollution emissions has theultimate objective of protectingpublic health and the environ-ment. However, to meet thisgoal, the contribution fromagriculture, specifically theimpact of burning practices onair quality, must be accuratelyassessed. But, until we have thenecessary research data tomake these decisions, it isnecessary for sugarcanefarmers to continue burningin keeping with the CertifiedPrescribed Burn ManagerProgram.

Burning of sugarcane beforeharvest eliminates from 30percent to 50 percent of theleafy trash (residue), whichconstitutes from 20 percent to25 percent of the total weightof the plant.


Carrie Borel, research associate, (top left) helped teach farmershow to do prescribed burns during the series of training sessionsin 2000. This session was at the St. Gabriel Research Station.

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Exposure of sugarcane to damaging frosts occurs in abouta fourth of the sugarcane-producing countries but is mostfrequent in the United States, particularly in Louisiana. Here,winter freezes have forced the industry to adapt to a shortgrowing season (about nine months) and a short milling season(about three months), although in recent years the milling seasonhas been extended to about four months. Growers and proces-sors must work together to ensure that most of the harvest iscompleted before January, usually the coldest month. Withrecord crops harvested during the past three years, manygrowers and processors have had to extend the harvest untilmid January, thus increasing the chances of freeze damage.

The effects of low temperatures have been extensivelyreported. Temperatures between 32 degrees F and 25 degreesF do little more than kill terminal buds and cause leaves to brown.Although no stalk tissue is usually damaged and no souring(deterioration) takes place, dead leaves cannot produce sugar,and the stalk sucrose content remains stable until new leaves areproduced or a more severe freeze occurs. In some cases,sucrose content of the juice following freezing conditions of thismagnitude actually increases slightly one to two weeks after thefreeze, in part, because of dehydration of the stalk. Tempera-tures between 25 degrees F and 22 degrees F may kill leaves andboth terminal and lateral buds; varying amounts of internal stalktissue may be damaged. Temperatures below 22 degrees F kill allabove-ground parts of commercial varieties.

Following freeze injury, dead and dying cells are vulnerableto invasion by the bacterium, Leuconostoc mesenteroides.Thisbacterium, which is found everywhere in cane fields, consumessucrose and produces dextran as a byproduct. The bacteriumgains entry into the storage tissue through dead lateral buds andfreeze cracks. When the frozen tissue thaws, cane juice may leakout at these points. It has been found that the concentration ofdextran in the juice is one of the more sensitive criteria indetermining the resistance of varieties to deterioration follow-ing a freeze.

Historically, five criteria besides dextran concentration ofjuice are sometimes used to measure the deterioration ofvarieties following freezing temperatures. They involve changesin the sucrose content of the juice, purity (relationship of thesucrose content to total soluble solids), sugar yield, pH and theacidity of the juice. The processor routinely measures sucrosecontent, purity and yield to determine cane quality of a grower’sconsignment for use in cane payment. Measuring the concentra-tion of dextran in the juice requires special training and is muchmore time consuming. Generally, the measurement of pH,acidity and dextran concentration are not conducted untildeterioration is suspected after a killing freeze. In recent years,it has been suggested that the concentrations of oligosaccha-rides or mannitol in the juice are more sensitive and betterindicators of deterioration than even dextran concentration.

In many cases, varietal differences in the amount of frozentissue are a factor in determining the rate of deteriorationfollowing a freeze. Cutting off cane tops with the harvester

Resistance of Louisiana SugarcaneTo Deterioration from Freezing Temperatures

removes the frozen tissue and consequently improves qualitybecause high acidity and dextran are generally not found in theundamaged part of the stalk. Further studies suggest that theresistance of tissue to freezing is not the sole mechanisminvolved since strong varietal differences are apparent in com-pletely frozen cane. It appears that when all the tissue of allvarieties is completely frozen by subfreezing temperatures,there may be varietal differences in keeping quality for as long astwo or more weeks after the freeze. Accordingly, this suggeststwo mechanisms at work—susceptibility of tissue to freezingand susceptibility to deterioration once the tissue is frozen.

Field experiments consisting of three row plots (18 feet by45 feet) are routinely planted at the U.S. Department ofAgriculture’s Ardoyne Farm at Houma, La., for estimating stalkcold tolerance. For the 2000-2001 crop-year study, two com-mercial varieties, CP 70-321 and CP 79-318, with knownreaction to freezing temperatures were planted as controls. CP70-321 is known for excellent cold tolerance; whereas, CP 79-318 has little resistance to deterioration following freezingconditions. Other commercial varieties included LHo 83-153,LCP 85-384, HoCP 85-845 and HoCP 91-555.

The first freeze of consequence occurred on Dec. 20, 2000,when the minimum temperature recorded in the field at the farmwas 24 degrees F. Freezing temperatures occurred again on Dec.21, Dec. 30 through Jan. 5, 2001, and Jan. 9 and 10, 2001. Thelowest temperature of 22 degrees F was recorded on Jan. 4.Freezing conditions prevailed for 8 to 15 hours during eachfreeze. After the Jan. 4 freeze, no sound tissue was observed inany cane, and freeze cracks were abundant in all varieties. Canetops began to droop within days, and the overall condition of thecane deteriorated to the extent that the stalks lost all integrityand fell over onto the ground.

Little or no deterioration was evident for all six varietiesthrough 14 days after the initial freeze of Dec. 20. Samples taken22 days after the initial freeze (eight days after the freeze of Jan.4) showed significant harmful changes in juice quality for all sixcriteria (sucrose content, purity, sugar yield, pH, acidity anddextran concentration) investigated. By the 30th day all varietieshad deteriorated to the point where they were unacceptable forprocessing into sugar. Overall, the ranking of varieties for stalkcold tolerance, from best to worse, when considering all criteriastudied was as follows: CP 70-321, LHo 83-153, LCP 85-384,HoCP 85-845, HoCP 91-555 and CP 79-318. Accordingly, theclassification of resistance to deterioration for these varietiesfollowing the freezes that occurred during the 2000-2001harvest is as follows: Very Good – CP 70-321; Good - LHo 83-153; Good to Moderate – LCP 85-384; Moderate – HoCP 85-845; Moderate to Poor – HoCP 91-555; and Poor – CP 79-318.These results compare favorably with data obtained fromprevious years in which freezing conditions occurred.

Benjamin L. Legendre, Extension Sugarcane Specialist, LSU AgCenter,Baton Rouge, La.


Resistance of Louisiana SugarcaneTo Deterioration from Freezing Temperatures


Raw sugar is stored in warehouses before being transported to refineries. This is the St.James Sugar Cooperative in St. James, La., one of 17 mills in the state. Louisiana has two

refineries—one in Gramercy and another in Chalmette. Photo by John Wozniak

Experiments were conducted with different levels ofcane maturity, harvest speed and row length. Tests weredone with two different varieties. For each test, the scalereadings were summed and compared to the weigh wagon.The results showed the scale predicted the weigh wagon with89 percent accuracy.

Farmers who use the chopper harvester will be able tomeasure their sugarcane crop yields with this system. An-other benefit of using this system is that the farmer can almosteliminate the problem of overloading the tractor-trailerswith cane.

Caryn E. Benjamin, Graduate Student; Michael P. Mailander,Associate Professor; and Randy R. Price, Assistant Professor,Department of Biological and Agricultural Engineering, LSUAgCenter, Baton Rouge, La.

One important application of precision farming is yieldmapping. Yield maps provide site-specific information that canaid in managing fertilizer and pesticide rates. Yield maps consistof two variables, the crop spot yield (pounds) and the position(longitude, latitude) of that yield in the field.

LSU AgCenter scientists undertook a project involvingthe design and testing of a sugarcane yield monitoring systemmounted on a chopper harvester. The sugarcane yield moni-toring system was comprised of a yield sensor (scale), a dataacquisition system and a differential global positioning system(DGPS). A scale mounted in the floor of the elevator tookinstantaneous measurements of the cane yield (weight) di-rectly. A dump wagon equipped with a weighing system (weighwagon) was used for each test.

SCIENTISTS USE PRECISION FARMINGTo Monitor Sugarcane Yields


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Louisiana Agricultural Experiment StationLouisiana State University Agricultural CenterP.O. Box 25100Baton Rouge, LA 70894-5100

Inside:

When the Jesuit priests firstbrought sugarcane to Louisiana in1751, little did they know they werelaying the foundation for a $2 billionindustry. Page 4

Many sugarcane diseases havebeen controlled through developmentof resistant varieties, but this has notbeen the case for RSD. Page 10

Sugarcane farmers in southeastTexas and southwest Louisiana areconcerned about the possibleintroduction of the Mexican rice borer.

Page 17

This is the sugar mill at St. James, one of 17 in the state.According to the LSU AgCenter’s Agricultural Summary for 2000,sugarcane was grown on 491,994 acres, which was a new recordfor the Louisiana sugar industry. An estimated 457,554 acreswere harvested for sugar, with a total production of 1,549,198tons of sugar. Sugar produced per harvested acre was 6,772

pounds, and sugar produced per total acre (including acres used forseed) was 6,298 pounds or about 5 percent lower than the yieldreported in 1999. The gross farm value of $362,701,238, asreported in the crop production statistics, is 61 percent of the totalvalue of the sugar and molasses produced, with the remaining 39percent going to processing and marketing. Photo by John Wozniak

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Sugarcane Issue - LSU AgCenter/media/system/4/a/8/3/4a83c3029ef5… · Research Station and St. Gabriel Research Station, St. Gabriel, La. S OVERVIEW Photo by John Wozniak Photo by