SAINT MARTIN’S UNIVERSITY

The Effect of Organic and Inorganic Fertilizers on the Growth and Developmentof Carica papaya L.

Rosary FaleonoMay 4, 2007

Senior Seminar IIFinal Draft

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Table of Contents

Abstract…………………………………………………………………………..pg. 2

Introduction………………………………………………………………………pg. 2 - 6

Materials and Methods…………………………………………………………...pg. 6 - 8

Seed Management………………………………………………………...pg. 6 - 7

Application of Organic and Inorganic Fertilizer………………………….pg. 8

Measurements and Data Analysis……………………………………… pg. 9

Results….…………………………………………………………………………pg. 9 - 14

Discussion…………………………………………………………………………pg. 14 -16

Acknowledgments……………………………………….………………………..pg. 16 - 17

Literature Cited………………………………………….………………………..pg. 18

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ABSTRACT

The frequent use of fertilizers is important for the production of agriculture around the

world today. Carica papaya L. is a tropical fruit plant, a widely consumed agricultural product

for its production of papaya fruit. I hypothesized that organic fertilizer applied on a weekly basis

would generate a faster growth rate in Brazilian Sunshine papaya plants compared to inorganic

fertilizer. I used Miracle-Gro® Water Soluble All Purpose Plant Food as the inorganic fertilizer

and Alaska Fish Emulsion as the organic fertilizer. The control group was treated with tap water.

The growth rates were measured after germination for a total of four weeks. When all data had

been collected, I used Analysis of Variance tests to compare the growth rates and development of

leaf width, leaf length, and stem height among the inorganic, organic, and water treatments. My

results did not show significant differences among the growth and development of papaya plants

treated with water, organic fertilizer, or inorganic fertilizer. Also, there were no differences in

the growth and development of the papaya plants between the use of either fertilizer or water.

All the papaya plants steadily increased in size.

INTRODUCTION

Carica papaya L., commonly known as papaya in the United States is a large, woody,

fruit-bearing plant believed to have originated either from Central America or southern Mexico.

Papayas are only found in places where the weather is warm, approximately 22°C to 26°C, and

are located in every tropical and subtropical region around the world. Papayas are famous for

their fruit, also called papaya, that are pear-shaped and taste somewhat like cantaloupe. There

are many types of papaya. Homestead Selection papaya, Solo Line 8 papaya, and Brazilian

Sunshine papaya are just a few members of the papaya family (Dedolph, 1962; Aiyelaagbe et al.,

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1985). There was no particular reason why I decided to use Brazilian Sunshine papaya other

than the fact that it germinates in a matter of a few weeks under proper care.

The frequent use of fertilizers is an important part of agricultural production around the

world (Chand et al., 2006). For several years, major crop producers have preferred the use of

inorganic fertilizers due to its high yield in crop productivity. However, long-term applications

of inorganic fertilizers have caused a noticeable decrease in crop productivity and an increase in

pollution around its surrounding environment (Chand et al., 2006). Recently, many agricultural

companies have shifted from using inorganic fertilizers to organic fertilizers (Luo et al., 2006).

A study was conducted to determine the yield responses and leaf nutrient concentrations

broiler chicken manure had on lima bean production (Luo et al., 2006). Two fertilizers were

tested: organic broiler manure (BM) and inorganic ammonium nitrate (AN). During the first

year, both fertilizers were applied all at once with no further applications of fertilizers for that

year. On the second year, BM treatments were applied only once and AN treatments were split

into three separate, but equal applications. Along with the fertilizers, water was also applied to

the lima beans by the use of an overhead sprinkler. After the 2-year period, the crops were

harvested and lima bean yield was determined. Results from the study showed variance in leaf

nutrient concentrations, but fresh pod yields were an equal amount or higher with BM treatment

than AN treatment (Luo et al., 2006). These results were similar to those from previous studies

with the same fertilizers on sweet corn, cabbage, and forages, which are crops grown to feed

livestock.

Due to the low yield production of agriculture with the use of organic manures, the

application of organic fertilizers with little or no fossil fuel-based inorganic fertilizers is rapidly

gaining favor (Anwar et al., 2005). In 2005, Anwar et al. studied the effect of a combination of

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organic manures and inorganic fertilizers on the growth and quality of essential oil of European

and Reunion basil crops. There were six treatments (T) used to grow the basil crops. T1 was the

control consisting of only water; T2 was the farm yard manure (FYM); T3 was the

vermicompost, an organic fertilizer consisting of a mixture of partially decomposed organic

waste, bedding, and worm castings; T4 was the inorganic fertilizer, a standard mixture of

nitrogen, phosphorous, and potassium (NPK); T5 was a combination of FYM and NPK fertilizer;

and T6 was a combination of vermicompost and NPK fertilizer. The setup was a randomized

block design (RBD) with four replications of each plant. The treatments consisting of FYM,

vermicompost, and NPK fertilizer alone were applied to the soil before planting. The two

combination treatments were applied twice, once at the time of planting and an equal amount

was applied a month after planting. After a period of 3 months, the crops were harvested. The

essential oil from each plant was extracted, and fresh weights were recorded in each plot.

Results showed that the application of T2 thru T6 showed a significant increase in fresh

weight, dry matter, and oil yield in the basil crop over the control (T1). The application of FYM

alone showed the lowest increase over the control and the application of a combination of

vermicompost with NPK fertilizer showed the highest increase over the control followed by the

combination treatment of FYM and NPK fertilizer. Mean herb yield of the plants grown with

NPK fertilizer alone was significantly higher than the treatments consisting of either of the

organic manures applied alone. However, each of the combination treatments resulted in greater

fresh weight yield and dry matter yield than the organic or inorganic fertilizers alone. Previous

studies conducted by Patra et al. (2000) and Chand et al. (2001) also reported similar results in

menthol mint crops. At the end of the study, Anwar et al. (2005) concluded that the application

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of organic manure, combined with a minimum dose of inorganic fertilizer, was better than

inorganic fertilizer or organic manure alone for yield, nutrient uptake, and quality of basil.

A similar field experiment was conducted by Chand et al. (2006) on mint and mustard

crops in subtropical India. The setup was also similar, consisting of a RBD with 8 combination

treatments composed of different ratios of FYM and inorganic fertilizer and replicated three

times. T1 was the control, T2 was FYM alone, and T3 to T8 were inorganic fertilizers with

different NPK (nitrogen-phosphorous-potassium) ratios mixed with various amounts of FYM.

All treatments were applied continuously to the crops for 7 years.

First, the mint seeds were planted, immediately followed by irrigation. Irrigation was

then applied every 10 – 15 days (Chand et al., 2006). Half of each treatment was applied at the

time of planting, and the remaining half was applied 48 days after planting. At maturity, the crop

was harvested and weighed. Dhaincha, a weed commonly grown in India to restore nitrogen to

depleted soils, was sown and plowed down after 45 days to allow for its decomposition. Next,

mustard seeds were sown and a full supply of NPK fertilizer was applied. The crop was

harvested 4 months later and weighed. Results from the experiment showed that the highest

increase in dry matter was in T4, which was NPK 133:40:40 fertilizer mixed with an equal

amount of FYM as in T3, with an increase of 92.8% over the control (T1). Chand et al. (2006)

concluded that a combination of organic manure and inorganic fertilizer increased the yield and

dry matter of mint and mustard crops.

The purpose of my research study was to measure the effects of organic and inorganic

fertilizers on the growth and development of Carica papaya L. The plants were grown in a

controlled environment under warm, moderate temperatures with three different treatments of

fish manure, inorganic fertilizer, and water to promote plant growth. This experiment examined

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the rates at which the fertilizers increased the growth of papaya plants. I hypothesized that the

use of 100 ml of organic fertilizer on Brazilian Sunshine papaya plants on a weekly basis would

generate faster growth compared to the application of 100 ml of inorganic fertilizer or water,

because previous studies had concluded that organic manures mixed with little inorganic

fertilizer increases the growth of agricultural products.

MATERIALS AND METHODS

Seed Acquirement and Management

Papaya plants are fast growing, woody, tropical plants that produce flowers and fruits.

Papaya plants are easy to grow from seeds, producing mature fruit within 9 - 12 months after

sowing (Gonsalves, 1998). However, papaya fruit are sensitive to changes in climate. Fruit

production can be affected by climatic factors such as drought and extremely cold or warm

temperatures (Aiyelaagbe et al., 1986). The plant itself is susceptible to changes in climate and

can also be affected by drought or extreme temperature changes.

The papaya seeds used for this study were Carica papaya Brazilian Sunshine, ordered

from Trade Winds Fruit (www.tradeswindsfruit.com/order.htm). Three greenhouses were

constructed to house the papaya seeds, and 2 trays were placed in each greenhouse to hold the

runoff water. Each greenhouse contained two 40 watt fluorescent bulbs as a source of light and

heat for the plants. The lights were placed 12 inches above the plants so as not to cause

excessive heat that might burn the seeds or plants. There were 60 replicates using thirty 32-

ounce transparent plastic cups per experimental group. Transparent cups were used to allow

observation of root growth of the papaya plants. Using small scissors, the bottom of each cup

was punctured with five small holes about 0.7 mm in diameter for water drainage from the soil.

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Each cup was ¾ filled with a soil made with a mixture of 1 part vermiculite and 1 part

Greensmix® potting soil (Waupaca Northwoods LLC, Waupaca, WI). Vermiculite was used in

order to help the papaya plants increase their absorption of moisture and nutrients when applying

the fertilizers or water. The seeds were divided into three sampling units, with 60 seeds per

group: 1) inorganic fertilizer, 2) organic fertilizer, and 3) control group of water. The soil was

warmed overnight to raise the temperature of the soil to between 18°C-38°C, because this was

the optimal range for successful papaya growth (Alarcon et al., 2002). The next day, the

temperatures were checked with a digital thermometer. Noting that the soil in each cup had

reached the desired temperature range, two seeds were planted in each cup, approximately one

inch into the soil, allowing room for root growth. I placed 10 transparent cups per experimental

group, 5 cups per tray, in each greenhouse as shown in Figure 1.

Inorganic

Organic

Water (Control)

Figure 1. The positioning of the experimental groups in each greenhouse. This was the order in which all the plants were set up in each greenhouse.

The greenhouses were covered with large transparent garbage bags to trap the heat from

the light fixtures inside the greenhouses. I also turned the thermostat up in the lab to warm the

room to the minimum/maximum temperatures of 23.7/26.4°C, the optimal temperature range for

papaya growth. Light from the light fixtures were left for 24 hours per day. I recorded the

temperature of each greenhouse before applying the fertilizers and water to make sure the

greenhouse temperatures were within the optimum range for papaya growth.

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Application of Organic and Inorganic Fertilizer

The inorganic fertilizer solution was made with ¼ teaspoon of Miracle-Gro® Water

Soluble All Purpose Plant Food (Scotts Miracle-Gro, Marysville, OH) containing 15 parts

nitrogen to 30 parts phosphorous to 15 parts potassium, or an NPK of 15-30-15, in 1L of water.

The organic fertilizer solution was made with 1 teaspoon of Alaska Fish Emulsion (Lilly Miller

Brands, Walnut Creek, CA) with an NPK of 5-1-1 in 1L of water. The solutions were made in

compliance with the manufacturer’s instructions. At the time of planting, 100 ml inorganic

fertilizer solution was applied to each pot in the inorganic fertilizer experimental group, 100 ml

organic solution was applied to each pot in the organic fertilizer experimental group, and 100 ml

tap water was applied to each pot in the control group. For the inorganic and control groups,

treatments were applied weekly, unlike the organic group with treatment occurring every two

weeks according to the manufacturer’s instructions. Water was applied to the organic group

every other week when organic fertilizer was not applied. The amount of water applied to the

control group was based on a study that measured the required average values of water needed

for growth of the papaya plant (Aiyelaagbe et al., 1985).

Measurements and Data

At the end of each week, for a total of 4 weeks, measurements were taken from each

plant with a centimeter ruler. Measurements for leaf length started from where the bottom of the

leaf and the stem touched to the tip of the leaf, leaf width was measured from the widest part of

the leaf, and stem height was measured from the bottom of the stem just above the dirt to the

closest branch of sprouting leaves from the bottom. Twelve Analysis of Variance (ANOVA)

tests were run to compare the mean growth of leaf length, leaf width, and stem height among the

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inorganic fertilizer, organic fertilizer, and control per week. The ANOVA tests determined

whether there were statistical significant differences in growth among the 3 treatments per week.

If there were any significant differences in growth of leaf length, leaf width, or stem height for

the experimental groups, then I used Tukeys multiple comparisons tests for further analysis of

the data using MiniTab (Version 15.0, January 2007, Minitab Inc., State College, PA).

RESULTS

The rate of growth and development for the inorganic group, organic group, and control

group were determined by averaging the measurements of leaf width, leaf length, and stem

height of all the plants on a weekly basis.

Table 1 shows the mean growth for plants grown under inorganic fertilizer, organic

fertilizer, and water treatments. Measurements of leaf width, leaf length, and stem height were

taken after seed germination and each week prior before fertilizing or watering the plants. At the

first week, 14 inorganic plants, 7 organic plants, and 13 control plants were measured. At week

two, 14 inorganic plants, 7 organic plants, and 10 control plants were measured. At week three,

15 inorganic plants, 9 organic plants, and 14 control plants were measured. At week four, 17

inorganic plants, 10 organic plants, and 17 control plants were measured. Twelve one-way

ANOVA tests were run to compare the growth of leaf width, leaf length, and stem height among

the inorganic, organic, and water treatments per week. Tukeys multiple comparison tests were

used to further analysis my data.

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Table 1. Means of leaf width, leaf length, and stem height of Carica papaya ‘Brazilian Sunshine’ treated with inorganic and organic fertilizers, and water. Values were determined based on growth per week and not over time. Data in this table is the same for the following figures.

Leaf WidthWeek 1 Week 2 Week 3 Week 4

Inorganic 1.4 2.1 2.9 3.3Organic 1.3 1.9 2.8 3.3Control 1.5 2.3 3.1 3.2

Leaf LengthWeek 1 Week 2 Week 3 Week 4

Inorganic 1.9 2.9 3.8 4.0Organic 1.7 2.6 3.7 4.1Control 2.0 3.1 3.7 3.7

Stem HeightWeek 1 Week 2 Week 3 Week 4

Inorganic 3.5 4.0 4.2 4.3Organic 3.5 4.0 3.9 4.0Control 3.9 4.4 4.0 4.0

Figure 2 shows the mean size and standard deviation at the first week of measurements.

Each bar represents the growth of each experimental group for the three parameters that were

measured. Growth obtained from the inorganic fertilizer group, organic fertilizer group, and

control group using a Tukeys multiple comparisons test showed no significant differences for

leaf width (F = 0.57; d.f. = 2; P = 0.570), leaf length (F = 0.99; d.f. = 2; P = 0.374), and stem

height (F = 2.12; d.f. = 2; P = 0.138).

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Week 1

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Leaf Width Leaf Length Stem Height

Plan

t gro

wth

(cm

) f

Inorganic

Organic

Control

Figure 2. The measurements of papaya leaf width, leaf length, and stem height obtained from inorganic, organic, and water treatments. Each bar represents the average growth of leaf width, leaf length, and stem height for the first week of measurements. There were 14 plants measured in the inorganic group, 7 plants in the organic group, and 13 plants in the control group. Each error bar represents one standard deviation from the mean.

Figure 3 shows the mean size and standard deviation during the second week of

measurements. The graph shows that leaf width, leaf length, and stem height increased from the

first week. Growth obtained from the inorganic fertilizer group, organic fertilizer group, and

control group using a Tukeys multiple comparisons test showed no significant differences for

leaf width (F = 1.79; d.f. = 2; P = 0.170), leaf length (F = 1.24; d.f. = 2; P = 0.292), and stem

height (F = 1.10; d.f. = 2; P = 0.346).

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Week 2

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Leaf Width Leaf Length Stem Height

Plan

t gro

wth

(cm

) d

Inorganic

Organic

Control

Figure 3. The measurements of papaya leaf width, leaf length, and stem height obtained from inorganic, organic, and water treatments. Each bar represents the average growth of leaf width, leaf length, and stem height for the second week of measurements. There were 14 plants measured in the inorganic group, 7 plants in the organic group, and 10 plants in the control group. Each error bar represents one standard deviation from the mean.

Figure 4 shows the mean size and standard deviation during the third week of

measurements. The graph shows that while leaf width and leaf length have continued to increase

in growth, there is a slight decrease in growth for stem height. Growth obtained from the

inorganic fertilizer group, organic fertilizer group, and control group using a Tukeys multiple

comparisons test showed no significant differences for leaf width (F = 0.42; d.f. = 2; P = 0.656),

leaf length (F = 0.11; d.f. = 2; P = 0.897), and stem height (F = 0.34; d.f. = 2; P = 0.712).

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Week 3

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Leaf Width Leaf Length Stem Height

Plan

t gro

wth

(cm

) f

Inorganic

Organic

Control

Figure 4. The measurements of papaya leaf width, leaf length, and stem height obtained from inorganic, organic, and water treatments. Each bar represents the average growth of leaf width, leaf length, and stem height for the third week of measurements. There were 15 plants measured in the inorganic group, 9 plants in the organic group, and 14 plants in the control group. Each error bar represents one standard deviation from the mean.

Figure 5 shows the mean size and standard deviation during the fourth week of

measurements. The graph shows that leaf length and stem height are in the same measurements

with each other showing the same mean growth during this last week. However, growth

obtained from the inorganic fertilizer group, organic fertilizer group, and control group using a

Tukeys multiple comparisons test showed no significant differences for leaf width (F = 0.14; d.f.

= 2; P = 0.868), leaf length (F = 0.62; d.f. = 2; P = 0.540), and stem height (F = 0.61; d.f. = 2; P

= 0.546).

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Week 4

00.5

11.5

22.5

33.5

44.5

5

Leaf Width Leaf Length Stem Height

Plan

t gro

wth

(cm

)

i

InorganicOrganicControl

Figure 5. The measurements of papaya leaf width, leaf length, and stem height obtained from inorganic, organic, and water treatments. Each bar represents the average growth of leaf width, leaf length, and stem height for the fourth week of measurements. There were 17 plants measured in the inorganic group, 10 plants in the organic group, and 17 plants in the control group. Each error bar represents one standard deviation from the mean.

DISCUSSION

My hypothesis was that the use of organic fertilizer will contribute to faster growth and

development of papaya plants than the use of inorganic fertilizer or water, because it does not

contain harmful chemicals and is healthy for the plants. However, the results of my research did

not show any significant differences among the growth and development of plants treated with

water, organic fertilizer, or inorganic fertilizer. Also, there were no differences in the growth of

the papaya plants between the use of either fertilizer and the use of water. Since p-values for

each week was greater than 0.05, I rejected my null hypothesis.

There was a noticeable trend in my data that all papaya plants steadily increased in

growth. An important factor to consider was the successful germination of papaya seeds,

because of the frequent failures of papaya seed germination in greenhouse and laboratory

experiments (Lange, 1961). Sawant (1958) studied low temperatures, approximately 4.4°C and

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below, are lethal to papaya species. The weather conditions here in Lacey, Washington during

the time of the experiment were not favorable for papaya growth. Although the plants were

grown indoors, the temperature of the lab was maintained at the optimal temperature range

between 18-38°C for the survival of the plants.

The most obvious reason why my hypothesis was rejected is that there is no difference

between the use of organic and inorganic fertilizers or that organic fertilizer is not better than

inorganic fertilizer for faster growth of papaya plants. So, for future experiments, I recommend

testing different types of organic and inorganic fertilizers. Organic manures like broiler manure,

farmyard manure, wood ash, and bone-meal could be used for organic fertilizer to test which one

is best for papaya growth. Inorganic fertilizers with different NPK ratios could also be used to

test growth of papaya plants to see which one works best for faster growth. I also recommend

testing different varieties of papaya to test which one grows faster. I also recommend expanding

the time of the experiment between 6 to 9 months, instead of a short period of 8 weeks. The data

might show different results in papaya growth. Also, the productivity of fruit could play a major

role in determining which treatments yield the highest dry weight of papaya fruit. Instead of

starting measurements when the first leaves had developed, germination of the seeds should be

measured first to keep track of the first plants that sprouted. I recommend measuring the leaf

width and leaf length on each plant as I did in the later part of my experiment rather than in

earlier measurements when I measured the leaf length of all the leaves first, then went back to

measure leaf width.

There are several ways to maintain the productivity of agriculture. The use of fertilizers,

inorganic and organic alike, play a major role in the production of agriculture worldwide (Chand

et al., 2006). However, the use of inorganic fertilizer on crops over a period of several years

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may cause long-term damage to the agriculture and the surrounding economy (Chand et al.,

2006). Organic fertilizer is rapidly growing in favor, because it provides and recycles

supplemental nutrients to crops and its non-chemical components greatly reduces waste products

(Luo et al., 2006).

The incorrect fertilizer on papaya plants could lead to failure of germination or growth in

laboratory and greenhouse experiments, or might not increase growth in the plants. This is the

case for all plants, but the ability of Carica papaya L. plants to grow up to 12 feet tall in one year

compliments its uniqueness. These exotic, tropical plants are fast growing producing fruit within

9-12 months after the seeds are planted (Gonsalves, 1998). Not many plants are known to

produce fruit or produce fruit in a matter of months. Therefore, researching or testing the best

fertilizer for faster growth of papaya plants may get you papaya fruits sooner than later.

ACKNOWLEDGEMENTS

I would like to give special thanks to the following individuals for there continued

support and guidance during my senior research project. I would like to thank Dr. Mary Jo

Hartman for helping me with my literature reviews, editing my papers, analyzing my results, and

also helping to put together my results for my final presentation. I would also like to thank Dr.

Margaret Olney for helping me with questions concerning the maintenance of my plants, editing

my papers, giving much needed constructive criticism, and always keeping a good attitude

throughout the year. Much appreciation goes out to lab technician Cheryl Guglielmo for her

helpful tips on soil and fertilizers to use for my project and also for helping to order the lab

equipment and papaya seeds for my experiment. I also thank my friends, Si’i Vulangi and Agnes

Uti for escorting me to lab during the late night hours and for lending a helping hand towards

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treating my plants. Last, but definitely not least, I would like to thank these special individuals,

Pelenita Tu’upo, Krystle Antolin, Sothear Sam, and Sonya Ramos for their much needed

constructive criticism and guidance throughout the entire research process. I am grateful for

these individuals and appreciate all their help with much gratitude.

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LITERATURE CITED

Aiyelaagbe, I.O.O., Fawusi, M.O.A., Babaloa, O. 1985. Growth, development and yield of pawpaw (Carica papaya L.) ‘Homestead selection’ in response to soil moisture stress. Plant and Soil. 93: 427-435.

Alarcon, A., Davies, F.T.D. Jr., Egilla, J.N., Fox, T.C., Estrada-Luna, A.A., Ferrera-Cerrato, R. 2002. Short term effects of Glomus claroideum and Azospirillum brasilense on growth and root acid phosphatase activity of Carica papaya L. under phosphorous stress. Revista Latinoamericana de Microbiologia. 44: 31-37.

Anwar, M., Patra, D.D., Chand, S., Alpesh, K., Naqvi, A.A., Khanuja, S.P.S. 2005. Effect of organic manures and inorganic fertilizer on growth, herb and oil yield, nutrient accumulation, and oil quality of French basil. Communications in Soil Science and Plant Analysis. 36: 1737-1746.

Chand, S., Anwar, M., Patra, D.D. 2006. Influence of long-term application of organic and inorganic fertilizer to build up soil fertility and nutrient uptake in mint-mustard cropping sequence. Communications in Soil Science and Plant Analysis. 37: 63-76.

Dedolph, R.R. 1962. Effect of benzothiazole-2-oxyacetate on flowering and fruiting of papaya. Botanical Gazette. 124: 775-78.

Gonsalves, D. 1998. Control of papaya ringspot virus in papaya: a case study. Annu. Rev. Phytopathol. 36: 415-437.

Lange, A.H. 1961. Effect of the sarcotesta on germination of Carica papaya. Botanical Gazette. 122: 305-311.

Luo, Y.G., Muchovej, R.M., Hanlon, E.A. 2006. Response of lima bean to inorganic nitrogen and broiler manure sources and rates. Communications of Soil Science and Plant Analysis. 37: 587-603

Minitab ® Release 14.20.2005. Minitab Inc.O’hara, B.P., Hemmings, A.M., Buttle, D.J., Pearl, L.H. 1995. Crystal structure of glycyl

endopeptidase from Carica papaya: a cysteine endopeptidase of unusual substrate specificity. Biochemistry. 34: 13190-13195.

Sawant, A.C. 1958. Crossing relationships in the Genus carica. Evolution. 12: 263-266.

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