Shank and Drip applied Soil Fumigants as Shank and Drip applied Soil Fumigants as Potential Alternative to Methyl Bromide Potential Alternative to Methyl Bromide

in Californiain California--grown Cut Flowersgrown Cut Flowers

Husein AjwaUniversity of California-Davis

Shank and Drip applied Soil Fumigants as Shank and Drip applied Soil Fumigants as Potential Alternative to Methyl Bromide Potential Alternative to Methyl Bromide

in Californiain California--grown Cut Flowersgrown Cut Flowers

Susanne Klose, H.A. Ajwa, S. Shem-Tov, S.A. Fennimore,K.V. Subbarao, J.D. Mac Donald, H. Ferris, F. Martin,

J. Gerik, M.A. Mellano and I. Greene

University of California-Davis,USDA-ARS Salinas and Parlier,

Mellano & Co. Carlsbad,Golden State Bulb Growers,

Moss Landing

Soil Fumigation for Soil Fumigation for Calla Lily Calla Lily and and RanunculusRanunculusProductionProduction

Key Diseases in selected Ornamentals Key Diseases in selected Ornamentals controlled by MB/Piccontrolled by MB/Pic

From MB CUE Nominations for Ornamentals, 2008 From MB CUE Nominations for Ornamentals, 2008

Crop Key Pest

Calla lily Erwinia soft rot (Erwinia carotovora)Pythium root rot (Pythium spp.)

Gladiolus Fusarium wilt (Fusarium oxysporum fsp. gladioli)Stromatinia neck rot (Stromatinia gladioli)

Ranunculus Pythium root rot (Pythium spp.)Xanthomonas leaf spot (Xanthomonascampestris)

Root rot (“Water mold”)

Key pests in Calla liliesKey pests in Calla lilies

Key Weeds and Nematodes in Ornamentals Key Weeds and Nematodes in Ornamentals controlled by MB/Piccontrolled by MB/Pic

From MB CUE Nominations for Ornamentals, 2008 From MB CUE Nominations for Ornamentals, 2008

Weeds

Bulbs, tubers, cormlets from previous crop

Yellow nutsedge, little mallow, common sow thistle, clover, others (?)

Most soil nematodes (Meloidogyne spp.)

Yellow Nutsedge

Field Trials

Comparison of pre-plant (1) shank and (2) drip-appliedalternative fumigants under two mulch types (standard HDPE and VIF) in two model crops in California: Calla lily (Moss Landing) and Ranunculus (Carlsbad)

Pre-plant shank rates (HDPE and VIF):

350 lbs/acre MB/Pic (67/33)

300 lbs/acre Midas (50/50)

Untreated Control

Field Trial 1 – Shank applied fumigants & VIF and standard (HDPE) mulch

Field Trial 2 – Drip applied alternative fumigants & VIF and standard (HDPE) mulch

1) All fumigants were applied under HDPE and VIF mulch. 2) Sequential metam-K or metam-Na application of 37.5 or 50 gal/A to ½ of the

plots of all treatments.

Treatment Rate (lbs/acre)1,2)

Untreated Check 0

MB/Pic (67/33) 200

Pic 200

InLine 300

Midas (33/67) 200

TestsWeed control efficacy

Survival of six common weed seeds and of volunteers (bulbs and/or seeds) (sachet test)Numbers of native weeds and major weed species Weeding times

Plant pathogen and nematode control efficacySurvival of five soil-borne pathogens and citrus nematode (sachet test)Presence of general soil fungi and Pythium spp. in soil

Tests - continued

Plant growth and yield parameters Stand densityDisease incidents Flower counts (Calla lily)Flower stem yield (Ranunculus)Bulb yield and quality (circumference, disease incidents)

Weed control by MB alternative fumigants

Seed viability (%)Seed viability (%)TreatmentTreatment Rate Rate

lbs/aclbs/acPlastic Plastic typetype ChickweedChickweed KnotweedKnotweed Mallow Mallow PurslanePurslane

HDPEHDPE

VIFVIF

HDPEHDPE

VIFVIF

nonenone

00 00 3737 00 00

00 00 2626 00 00

00 00 3939 00 00

00 00 2929 00 11

ControlControl 00 7171 9797 5050 7373 4242

Midas Midas (50/50)(50/50) 300300

MB/Pic MB/Pic (67/33)(67/33) 350350

NutsedgeNutsedge

Weed seed survival in shank-fumigated soils

Midas provided similar control of flower bulbs (Calla, Gladiolus, Ranunculus) and seeds (Ranunculus) as the standard MB/Pic mix

Native weed populations in shank-fumigated soils (Ranunculus system)

Weed density (No./acre)Weed density (No./acre)TreatmentTreatment Rate Rate

lbs/aclbs/acPlastic Plastic typetype MalvaMalva CloverClover Fescue Fescue Swine Swine

cresscress

HDPEHDPE 4,901 a4,901 a 170,701170,701 00 00 1818 4,5254,525

VIFVIF 6,534a6,534a 130,727130,727 4,9014,901 00 1515 2,5812,581

HDPEHDPE 817b817b 164,984164,984 00 00 1010 5,0185,018

VIFVIF 0b0b 151,916151,916 00 00 1313 3,7343,734

ControlControl 00 nonenone 817b817b 178,052178,052 00 1,6341,634 1313 4,5154,515

Midas Midas (50/50)(50/50) 300300

MB/Pic MB/Pic (67/33)(67/33) 350350

Cover Cover %%

Weed Weed biomass biomass g/acreg/acre

Weed control with drip applied alternatives Weed control with drip applied alternatives (standard HDPE mulch)(standard HDPE mulch)

Fumigant Vapam Yellow Nutsedge Chickweed Knotweed Mallow Purslane Calla lilyC. esculentus S. media P. arenastrum M. parviflora P. oleracea Zantedeschiaspp.

Untreated - 60 62 98 70 86 53+ 39 32 49 54 48 44

MB/Pic - 10 0 8 53 1 13+ 0 0 5 46 0 25

Midas - 1 0 17 44 0 13+ 6 0 11 45 12 6

InLine - 26 0 31 53 10 31 + 21 0 22 44 0 28

CP - 33 0 43 50 1 16+ 23 0 25 45 3 19

Viability of weed seeds and flower bulbs (%)

Similar weak control of bulbs of Gladiolus and Iris by all drip applied fumigants; control of volunteer bulbs by Midas and MB/Pic under VIF

Burial, fumigation and retrieval of nylon bags with soil-borne pathogens and nematodes

Pathogen control by MB alternative fumigants

0

20

40

60

80

100

120

140

160

VIF Std VIF Std VIF Std VIF Std VIF Std

Untreated MB/CP Midas Telone C35 CP

Fumigant Treatment/Plastic

Vert

icill

ium

dah

liae

(mic

rocl

erot

ia g

-1)

Verticillium dahliae survival in shank-fumigated soils (Error bars represent standard errors)

MB/Pic shank standard

Verticillium dahliae survival in drip-fumigated soils (Error bars represent standard errors)

020406080

100120140160180

VIF

HD

PE VIF

HD

PE VIF

HD

PE VIF

HD

PE VIF

HD

PE VIF

HD

PE VIF

HD

PE VIF

HD

PE VIF

HD

PE VIF

HD

PE

Untreated Untreated+ Kpam

MB/Pic MB/Pic +Kpam

Pic Pic +Kpam

InLine InLine +Kpam

Midas Midas +Kpam

Fumigant Treatment/Plastic

Vert

icill

ium

dah

liae

(mic

rocl

erot

ia g

-1)

MB/Pic shank standard

Fusarium oxysporum survival in shank-fumigated soils (Error bars represent standard errors)

0

100,000

200,000

300,000

400,000

500,000

VIF HDPE VIF HDPE VIF HDPE VIF HDPE VIF HDPE

Untreated MB/CP Midas Telone C35 CP

Fumigant Treatment/Plastic

Fusa

rium

oxy

spor

um (C

FU g-1

)

0

20

40

60

80

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

Untreated+ Kpam

MB/Pic MB/Pic +Kpam

Pic Pic +Kpam

InLine InLine +Kpam

Midas Midas +Kpam

Fumigant Treatment/Plastic

Fusa

rium

oxy

spor

um (

CU

F g-1

)

Untreated VIF = 443,333 CUF g-1

HDPE = 557,500 CUF g-1

100% control in MB/Pic shank standard

Fusarium oxysporum survival in drip-fumigated soils (Error bars represent standard errors)

Pathogen survival in shank fumigated soils

0

5

10

15

20

25

30

VIF HDPE VIF HDPE VIF HDPE VIF HDPE

MB/CP Midas Telone C35 CP

Fumigant Treatment/Plastic

Path

ogen

sur

viva

l (%

)re

l. to

unt

reat

ed s

oil

Pythium Verticillium

Complete control of Fusarium, Phytophthora and nematodes

Pathogen survival in drip fumigated soils

0

20

40

60

80

100

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

VIF

HD

PE

MB/Pic MB/Pic +Kpam

Pic Pic +Kpam

InLine InLine +Kpam

Midas Midas +Kpam

Fumigant Treatment/Plastic

Path

ogen

sur

viva

l (%

)re

lativ

e to

unt

reat

ed s

oil

RhizoctoniaVerticillium

Complete control of Fusarium, Phytophthora, Pythium spp. and nematodes

Yield data1. Flower stems

Calla lily stem harvest

Ranuncula bulb harvest

Yield data2. Flower bulbs

Flower Stem yield in shank-fumigated soils(relative to MB/Pic standard mix)(relative to MB/Pic standard mix)

0

20

40

60

80

100

120

140

none VIF HDPE VIF HDPE

Untreated MB/CP 350 Midas 300

Fumigant Treatment/Plastic

Ran

uncu

lus

stem

yie

ld (

% to

MB

/Pic

HD

PE)

MB/Pic standard

Flower bulb yield in shank-fumigated soils((RanunculusRanunculus system)system)

Treatment Plastic No kg No kg No kg

UTC none 36,777 151 44,802 134 305,168 537MB/Pic HDPE 51,966 245 37,542 119 198,484 503

VIF 39,548 178 42,548 107 201,293 442Midas HDPE 46,865 220 35,727 92 182,245 436

VIF 44,133 205 36,109 90 210,731 409

n.s. n.s. n.s. n.s. n.s. n.s.ANOVA

TotalBulb yield per size (per acre)

8+ 7-8

No significant differences in all other bulb sizes

Flower Stem yield in drip-fumigated soils(relative to MB/Pic standard mix)(relative to MB/Pic standard mix)

0

20

40

60

80

100

120

140

- + - + - + - + - +

UTC MB/Pic Pic Midas InLine

Treatment/Sequential Kpam (+/-)VIF mulch

Ran

uncu

lus

stem

yie

ld(%

to M

B/P

ic s

hank

)

MB/Pic standard

Flower bulb yield in drip-fumigated soils((RanunculusRanunculus system)system)

No significant differences in all other bulb sizes

Fumigant Vapam

No kg No kg No kg

UTC - 8,981 a 32 a 17,209 a 30 a 97,365 a 135 a+ 14,574 a 54 a 25,652 a 46 a 107,125 a 164 a

MB/Pic - 26,486 b 105 b 29,901 ab 70 b 132,025 b 256 b+ 25,679 b 105 b 31,594 b 70 b 141,893 b 269 b

Pic - 37,510 bc 118 b 27,666 ab 76 b 142,619 b 285 b+ 27,642 b 116 b 35,843 b 81 b 140,495 b 280 b

Inline - 27,992 b 121 b 33,047 b 76 b 142,135 b 288 b+ 33,746 bc 143 c 29,040 ab 73 b 143,829 b 301 b

Midas - 36,193 bc 132 bc 44,609 c 100 c 194,918 c 352 c+ 36,515 bc 142 c 36,784 b 78 b 161,898 bc 309 b

0.000 0.000 0.005 0.003 0.032 0.000

Bulb yield per size (per acre)8+ 7-8

ANOVA (P -value)

Total

Conclusions – Ranunculus production

Shank-applied Midas (once registered in CA) at 300 lbs/acre was equally effective in providing weed and pathogen control.

Drip-applied alternatives at 200 lbs/ acre were not consistently effective as the MB/Pic shank standard at 350 lbs/acre

Bulb quality seemed to be better under drip fumigation than shank injection

Conclusions – Calla lily production

Drip fumigation resulted in better pest control and bulb yield and quality than shank fumigationDrip-applied Midas at 200 lbs/ acre and InLine at 300 lbs/acre are currently the best alternative treatments for multi-pest complex control in the absence of MB/PicAdvantage of VIF over HDPE mulch and of sequential application of Kpam or Vapam to improve fumigant efficacy in floricultural production could not consistently proven in these two systems

Acknowledgements

USDA-CSREESCalifornia Cut Flower Commission USDA-IR4 program

Golden State Bulb Growers (Ian Greene)Mellano & Co. (Mike A. Mellano, Mike Muehe)TriCal (Paul Niday, Mike Stanghellini, Bob Lino, Mark Lauman)Arysta LifeSciencesBruno Rimini Ltd & PolyPak

Cheryl Wilen, UCCE San DiegoJonathan Hunzie, Matthew Linder, Ernie Leyva, Patricia Martinez, Wonsook Ha, Stella Lee