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REPUBLIC OF RWANDA

MINISTRY OF EDUCATION

HIGHER INSTITUTE OF AGRICULTURE AND ANIMAL

HUSBANDRY (ISAE)

FACULTY OF AGRICULTURE AND RURAL

DEVELOPMENT

Presented by:

Donatien NIYIBIGIRA

For the Partial Fulfillment of the

requirement of the award of

Bachelor’s Degree in Horticulture

Research Supervisor:

Mr. NG’ETICH (MSc.)

Academic year: 2011

Effect of Organic and Inorganic Fertilizer on Growth and

Yield of Collards (Brassica oleracea var. acephala).

A case study of Musanze Rwanda.

i

DEDICATION

To:

Almighty God;

My family;

My beloved parents;

My brothers and sisters;

My friends and classmates;

I dedicate this memoir to them.

ii

DECLARATION

I, Donatien NIYIBIGIRA declare that this Memoir is an original research work supervised

by Mr. Onesmus NG’ETICH, and has not been published earlier in any other higher

institution. This memoir has been submitted for the partial fulfillment of the requirement

of the award of Bachelor’s Degree (Ao) In Horticulture at the Higher Institute of

Agriculture and Animal Husbandry (ISAE).

Student name:

Donatien NIYIBIGIRA:………………… Signature:….………………………

Date: …………………

Supervisor:

Mr. Onesmus NG’ETICH:………………. Signature..………………….……..

Date: …………………

iii

ACKNOWLEGDEMENTS

First and foremost, I thank the Almighty God for His abundant blessings, guidance and

protection during my studies in ISAE. I acknowledge the contributions of many scientists

which have been cited in this dissertation for detailed general information, and regret any

inadvertent omission. I deeply acknowledge the Government of Rwanda for offering the

second cycle in ISAE. I am also thankful to ISAE authorities for providing all necessary

facilities during the research work.

I acknowledge all the academic staff, especially the lecturers of the department of Crop

Production for their kind assistance in both theoretical and practical knowledge provided.

I highly feel indebted and full of gratitude to the Higher Institute of Agriculture and

Animal Husbandry especially to the lecturers in the Faculty of Agriculture and Rural

Development for the training they offered to me.

It is great pleasure for me to express my great sense of gratitude to my supervisor, Mr.

Onesmus NG’ETICH, for his valuable suggestions, constructive criticism and painstaking

efforts throughout the period of project work.

From the bottom of my heart, I would like to acknowledge my family and the family of

Mulindabigwi Desire for the moral support, advices, encouragements, love, joy and

sympathy expressed during this research.

I am thankful to my brothers, sisters, friends and classmates for their moral support during

the course of my study.

Finally any other who, near or far, feel have contributed to our intellectual development

and the achievement of this work, here are our heartfelt thanks.

Donatien NIYIBIGIRA

iv

ABSTRACT

Appropriate soil fertility is essential for increased and sustainable crop production.

However mineral fertilizers are expensive. An alternative way of overcoming the

problems of declining soil fertility is to use an integrated fertilization. As a result, an

experiment was carried out to find suitable fertilizer regime which could give an economic

yield of collard (Brassica oleracea var. acephala). This experiment was arranged in a

Randomized Complete Block Design with three replicates. Treatments were as following:

(T1): the control without any fertilizer, (T2): the combination of 150 kg/ha of N: P: K (17-

17-17) and 10 t/ha of Farmyard manure, (T3): 20 t/ha of farmyard manure alone and (T4):

300 kg/ha of N: P: K (17-17-17). These were applied as basal application of fertilizer in

this experiment. The parameters studied were; plant height, stem diameter and leaf area,

fresh yield, dry biomass yield, pH, Nitrogen, Phosphorus, Potassium and organic carbon.

The results of this study revealed that there were significant differences in plant height,

stem diameter and leaf area during the early stage of the growth and later. Higher yields of

223.0 t/ha was obtained from the plants subjected to the combination of both farmyard

manure and N: P: K (17-17-17) whereas the control gave the lowest yield (104.7 t/ha).

From this study, it could be stated that the combination of farmyard manure and N:P:K

(17-17-17) at the rate of 10 t/ha of farmyard manure and 150 kg/ha of N:P:K gives higher

yield (223.0 t/ha) and this combination could possibly reduce the cost of production in the

cultivation of collard. From the results, the leaf area from plants treated with 150 kg/ha of

N: P: K (17-17-17) and farmyard manure (10 t/ha) was significantly higher by 76%

compared to the control. The chemical soil analysis after the experimental period showed

that there was an increased of Nitrogen by 8.6%, Phosphorus by 43.8%, Potassium by

32.0% organic carbon by 7.4%, organic matter by 0.65% while there was a reduction of

pH and C/N ratio by 0.54% and 10.5% respectively for the treatment subjected to 150

kg/ha of N: P: K (17-17-17) and farmyard manure (10 t/ha). Therefore through the highest

yield obtained by use of the combination of both organic and inorganic fertilizer, we

recommend to the farmers the application of mineral fertilizers in combination of

Farmyard manure for maximizing collards production and at the same time improving the

physical, chemical and biological properties of the soil.

RESUME

v

La fertilité du sol appropriée est très importante pour l’augmentation et la production

végétale durable. Cependant, les engrais minéraux sont très chers. Un moyen alternatif de

dépasser les problèmes de baisse de fertilité du sol est d’utiliser la fertilisation intégrée.

C’est pourquoi une expérimentation a été conduite pour identifier lequel convenable

fertilisant qui pourrait donner un rendement économique de chou précoce (Brassica

oleracea var. acephala). Le dispositif expérimental est celui de blocs aléatoires

complètement randomisées avec trois répétitions qui étaient les suivants: (T1) : le témoin,

(T2) : la combinaison de 150 kg/ha de N:P:K (17-17-17) and 10 t/ha de fumure organique,

(T3) :20 t/ha de fumure organique seule et (T4) :300 kg/ha de N:P:K (17-17-17). Ceux-ci

ont été appliqués comme étant des fertilisants de base. Les Paramètres étudiés étaient : la

hauteur de plante, diamètre de la tige, surface de la feuille, le rendement frais des feuilles,

le rendement sec des biomasses, pH du sol, Azote, Phosphore, Potassium, et Carbone

organique. Les résultats de cette étude ont révélé qu’il y’ avait les différences

significatives dans les hauteurs de plantes, diamètre de la tige et surface du feuille durant

la croissance la plus jeune de la plante. Le plus haut rendement de (223.0 t/ha) a été obtenu

des plantes soumises à la combinaison de 150 kg/ha de N:P:K (17-17-17) et 10 t/ha de

fumure organique au moment où le témoin donnait le plus petit rendement (104.7 t/ha). De

cette étude on peut dire que la combinaison de fumure organique et N:P:K (17-17-17) a

donné un rendement profitable de (223.9 t/ha) et cette combinaison pourrait réduire le coût

de production dans la culture de chou précoce. De ces résultats, la surface des feuilles de

plantes traitées par 150kg /ha of N : P : K (17-17-17) et la fumure organique (10 t/ha)

étaient significativement grand par 76%par rapport au control. Les analyses chimique du

sol après l’expérience ont montré qu’il avait une augmentation d’azote 8.6%, phosphore

par43.8%, potassium par 32.0%, carbone organique par 7.4%, matière organique par

0.65% alors qu’il y avait une réduction du pH and le rapport de carbone et azote par 0.54%

et 10.5% respectivement pour les traitements traités par 150kg /ha of N : P : K (17-17-17)

et la fumure organique (10 t/ha). Cependant, de ce plus haut rendement obtenu de la

combinaison de la fumure organique et inorganique, nous recommandons aux agriculteurs

d’utiliser la combinaison de la fumure organique et inorganique pour maximiser la

production de choux précoces et d’améliorer à même temps les propriétés physique,

chimique et biologique du sol.

vi

vii

TABLE OF CONTENTS

DEDICATION .......................................................................................................................i

DECLARATION ..................................................................................................................ii

ACKNOWLEGDEMENTS .................................................................................................iii

ABSTRACT.........................................................................................................................iv

RESUME .............................................................................................................................iv

TABLE OF CONTENTS....................................................................................................vii

LIST OF TABLES ................................................................................................................x

LIST OF FIGURES .............................................................................................................xi

LIST OF APPENDICES.....................................................................................................xii

ACRONYMS AND ABREVIATIONS.............................................................................xiv

CHAPTER ONE ...................................................................................................................1

INTRODUCTION ................................................................................................................1

1.1 Background Information ...................................................................................................... 1

1.2. Problem Statement............................................................................................................... 2

1.3.1. General objective ................................................................................................ 2

1.3.2. Specific objectives .............................................................................................. 2

1.4. Hypotheses .......................................................................................................................... 3

CHAPTER TWO ..................................................................................................................4

REVIEW OF LITERATURE ...............................................................................................4

2.1. Overview of Collards .......................................................................................................... 4

2.1.1. Origin and Botanical Description ....................................................................... 4

2.1.2. Ecological requirement....................................................................................... 5

2.1.2. Horticultural production field practices.............................................................. 5

2.1.3. Nutritional value of collard................................................................................. 8

2.1.4. Role and Potential of Collard Green in Health Promotion ................................. 9

2.2. Effect of Fertilizers on Leafy Vegetables............................................................................ 9

2.2.1. Major or Macro-Nutrients .................................................................................. 9

viii

2.2.2. Functions of Macronutrients in Leafy Vegetables.............................................. 9

2.3. Effect of combine application of organic and inorganic fertilizer on leafy vegetable.......10

2.4. Time and Method of Fertilizer Application.......................................................................11

2.5. Composition of Farmyard manure.....................................................................................11

2.6. Fertilizer recommendations on collards, kales, cabbage and other related fodder crops. .12

CHAPTER THREE.............................................................................................................14

MATERIAL AND METHODS ..........................................................................................14

3.1. The experimental site ........................................................................................................14

3.2. Experimental Design and Treatment Application .............................................................15

3.3. Planting Materials..............................................................................................................16

3.4. Soil and Manure Nutrient Analysis ...................................................................................16

3.5. Mineral fertilizer (N: P: K 17-17-17) ................................................................................16

3.6. Other materials ..................................................................................................................16

3.7 Nursery bed preparation and sowing ..................................................................................17

3.8. Land Preparation and Treatment application.....................................................................17

3.9 Transplanting ......................................................................................................................17

3.10 Routine Management Practices ........................................................................................18

3.11. Data Collection ..................................................................................................18

3.11.1. Soil Sampling .................................................................................................18

3.11.2. Agronomic Parameters Measured ..................................................................19

3.11.3. Statistical Analysis .........................................................................................19

CHAPTER FOUR...............................................................................................................21

PRESENTATION AND INTERPRETATION OF RESULTS..........................................21

4.1. Effects of organic and inorganic fertilizers on soil chemical properties after transplanting

of collards..........................................................................................................................21

4.2. Effects of organic and inorganic fertilizers on plant height of Collard (cm).....................22

4.3. Effects of organic and inorganic fertilizers on number of leaves of Collard .....................23

4.4. Effects of organic and inorganic fertilizers on stem diameter (mm) of Collard ................24

4.5. Effects of organic and inorganic fertilizers on leaf area (cm2) of Collard.........................24

4.6 Effects of organic and inorganic fertilizers on Fresh weight (grams/plant) of Collard ......25

4.7 Effects of organic and inorganic fertilizers on oven-dry mass of edible leaves of Collard 26

ix

4.8 Effects of organic and inorganic fertilizers on Total fresh weight and Total oven-dry mass

of Collard ..........................................................................................................................27

CHAPTER FIVE.................................................................................................................13

DISCUSSION .....................................................................................................................13

5.1. Effects of organic and inorganic fertilizers on soil chemical properties after transplanting

of collards..........................................................................................................................13

5.2. Effects of organic and inorganic fertilizers on plant height of Collard in cm ...................15

5.3. Effects of organic and inorganic fertilizers on number of leaves of Collard.....................15

5.4. Effects of organic and inorganic fertilizers on stem diameter of Collard..........................16

5.5. Effects of organic and inorganic fertilizers on leaf area of Collard ..................................17

5.6. Effects of organic and inorganic fertilizers on Fresh and oven-dry mass of edible leaves of

Collard...............................................................................................................................17

5.7. Effects of organic and inorganic fertilizers on Total fresh weight and Total oven-dry mass

of Collard ..........................................................................................................................18

CHAPTER SIX ...................................................................................................................19

CONCLUSION AND RECOMMENDATIONS................................................................19

6.1 Conclusion ..........................................................................................................................19

6.2 Recommendations ..............................................................................................................20

REFERENCES. ........................................................................................................................21

APPENDICES ....................................................................................................................25

x

LIST OF TABLES

Table 1: Comparison of nutritional value between Collard and Cabbage ............................8

Table 2. The climatic data during the experimentation.......................................................14

Table 3: Effects of organic and inorganic fertilizers on soil chemical properties after

transplanting of Collard .......................................................................................22

Table 4: Effects of organic and inorganic fertilizers on plant height of Collard ................23

Table 5: Effects of organic and inorganic fertilizers on stem diameter (mm) of Collard ...24

Table 6: Effects of organic and inorganic fertilizers on Fresh edible yield of Collard.......26

Table 7: Effects of organic and inorganic fertilizers on oven-dry mass of edible leaves of

Collard..................................................................................................................27

xi

LIST OF FIGURES

Figure 1: Experimental layout.............................................................................................15

Figure 2: Sampling points in experimental plot. .................................................................18

Figure 3: Effects of organic and inorganic fertilizers on number of leaves of Collard after

15th and 25th day .................................................................................................23

Figure 4: Effects of organic and inorganic fertilizers on leaf area (cm2) of Collard ..........25

Figure 5: Effects of organic and inorganic fertilizers on total fresh weight and total oven-

dry mass of Collard (in grams). ..........................................................................13

Figure 6: Effects of organic and inorganic fertilizers on total fresh weight and total oven-

dry mass of Collard(T/ha)...................................................................................13

xii

LIST OF APPENDICES

Appendix 1:1Soil pH after harvesting after trial.................................................................25

Appendix 2: Nitrogen rate after harvesting (%)..................................................................25

Appendix 3: Phosphorus rate after harvesting (ppm) .........................................................26

Appendix 4: Potassium rate after harvesting (meq/100g)...................................................26

Appendix 5: Organic carbon after transplanting .................................................................27

Appendix 6: Organic matter after harvesting......................................................................27

Appendix 7: C/N ration.......................................................................................................28

Appendix 8: Effect of treatment on soil chemical ..............................................................13

Appendix 9: Interpretation norms of pH.............................................................................13

Appendix 10: Interpretation norms of O.M and available P, and total N ...........................13

Appendix 11: Number of leaves at 15th day after transplanting .........................................14

Appendix 12: Number of Leaves at 25th days after transplanting.......................................15

Appendix 13: Leaf area at 25th day after transplanting.......................................................15

Appendix 14: Plant height at 15th day after transplanting...................................................16

Appendix 15: Plant height at 25th day after transplanting (in cm) ......................................16

Appendix 16: plant height at 32th day after transplanting(cm) ...........................................16

Appendix 17: Plant height at the 39th day after transplanting (cm) ....................................17

Appendix 18: Plant height at the 46th day after transplanting.............................................17

Appendix 19: plant height at the 53rd day after transplanting (cm) ....................................17

Appendix 20: Stem diameter at 15th day after transplanting(mm)......................................18

Appendix 21: Stem diameter at 25th after transplanting (mm)............................................18

Appendix 22: Stem diameter at 32th after transplanting(mm).............................................18

Appendix 23: Stem diameter at 39th day after transplanting (mm).....................................19

Appendix 24 Stem diameter at 46th day after transplanting (mm) ......................................19

Appendix 25: Stem diameter at the 53rd day after transplanting (mm)...............................19

Appendix 26: Analysis of Variance of soil pH ...................................................................20

xiii

Appendix 27: Analysis of Variance of Total Nitrogen .......................................................20

Appendix 28: Analysis of Variance of available phosphorus .............................................20

Appendix 29: Analysis of Variance of available potassium ...............................................20

Appendix 30: Analysis of Variance of organic matter........................................................20

Appendix 31: Analysis of Variance of plant height at the 15th day ....................................21


Appendix 33: Analysis of Variance of plant height at the 32nd day....................................21


Appendix 35: Analysis of Variance of plant height at the 46th day ...................................21

Appendix 36: Analysis of Variance of plant height at the 53rd day....................................22

Appendix 37: Analysis of Variance of number of leaves at the 15th day............................22

Appendix 38: Analysis of Variance of number of leaves at the 25th day............................22

Appendix 39: Analysis of Variance of stem diameter at the 15th day.................................22


Appendix 41: Analysis of Variance of stem diameter at the 32nd day................................23



Appendix 44: Analysis of Variance of stem diameter at the 53rd day ................................23

Appendix 45: Analysis of Variance of leaf area .................................................................23

Appendix 46: Analysis of Variance of fresh weight at the 25th day ...................................24

Appendix 47: Analysis of Variance of fresh weight at the 39th day ...................................24

Appendix 48: Analysis of Variance of fresh weight at the 53rd day ...................................24

Appendix 49: Analysis of Variance of total fresh weight in t/ha........................................24

Appendix 50: Analysis of Variance of total fresh weight in grams/ha ...............................24

Appendix 51: Analysis of Variance of Total oven-dry mass in grams/ha ..........................25

Appendix 52: Analysis of Variance of Total oven-dry mass in tones/ha ...........................25

Appendix 53: Picture in the field from the beginning up to the end of the experiment......25

xiv

ACRONYMS AND ABREVIATIONS

ANOVA: -Analysis of Variance

C/N: -Carbon-Nitrogen ratio

FAO: -Food and Agriculture Organization

FYM: -Farm Yard Manure

GDP: -Gross Domestic Product

HSD: -Honestly Significant Difference

ISAE: -Institut Supérieur d’Agriculture et d’Elevage.

LA : -Leaf Area

MINAGRI: -Ministry of Agriculture and Animal Resources

MINALOC: -Ministry of Local government

N:P:K: -Nitrogen, Phosphate, Kalium (Potassium)

pH: -potential in Hydrogen

RCBD: -Randomized Complete Bloc Design

RHODA: -Rwanda Horticulture Development Agency

T/ha: -tons per hectare

Ttt: -Treatment

USA: -United States of America

USD: -United States Doll

1

CHAPTER ONE

INTRODUCTION

1.1 Background Information

The agricultural sector, remains at the center of Rwanda’s development and is now

recognized as the engine of growth that will drive poverty reduction in Rwanda and

improve the livelihood of its population (MINAGRI, 2007). Shifting cultivation, as

practiced by the traditional farmers to restore soil fertility in sustaining cropping can no

longer meet up with the increased need for food supply due to high population pressure.

The length of fallow period required to replenish the soil to maintain soil productivity has

to be shortened. The primary function of soil productivity and fertility restoration through

fallow is less effective since intensive cropping is now more common. The use of

inorganic fertilizers alone has not been helpful under intensive agriculture because it

aggravates soil degradation (Sharma and Mittra, 1991).

The degradation is brought about by loss of organic matter which consequently results in

soil acidity, nutrient imbalance and low crop yields. Any effort in crop production is

achieved through increasing productivity rather than expansion of production area. The

maximum productivity would be achieved through a combination of proper use of

improved agricultural techniques including fertilization. (MINAGRI, 2008).

Response of crops to applied fertilizer depends on soil organic matter. The quantity of soil

organic matter depends on the quantity of organic material which can be introduced into

the soil either by natural returns through roots, stubbles, sloughed-off root nodules and

root exudates or by artificial application in the form of organic manure which can

otherwise be called organic fertilizer (Agboola and Omueti, 1982).

The need to use renewable forms of energy has revived the use of organic fertilizers

worldwide. Nutrients contained in organic manures are released more slowly and are

stored for a longer time in the soil, thereby ensuring a long residual effect (Sharma and

Mittra, 1991). Improvement of environmental conditions and public health as well as the

need to reduce costs of fertilizing crops are also important reasons for advocating

increased use of organic materials (Seifritz, 1982). Application of organic manures also

improves the soil microbial properties (Belay et. al., 2001)

2

The benefits derivable from the use of organic materials is however not fully used in

Musanze .

Therefore, the present study was carried out to study the response of vegetative growth

and yield of the collard Brassica oleracea var. acephala, to applied organic manures

compared with mineral fertilization

1.2. Problem Statement

Rwanda is among countries in Sub-Saharan African and is experiencing high food

shortages. However, soil fertility is declining at alarming rate due to the limited use of

organic and mineral fertilizers, depletion of soil nutrients by continued cropping without

the use of fertilizers, soil erosion and farmers are unable to acquire fertilizers due to the

escalating market prices limiting its usage. The fore mention factors have led to continued

food shortages in the country. There are different ways to overcome the declining trends

in soil fertility including proper utilization of fertilizers which should provide part of

solution to plant requirement. Therefore, more emphasis is to be placed on technologies

and strategies to integrated use of both minerals and organic fertilizers. This is what

prompted me to conduct the study on effect of organic and inorganic fertilizers and the

combination of both on growth and yield of collard.

1.3.1. General objective

The main objective of the study is to evaluate the effect of organic and inorganic fertilizers

on growth and yield of collards (Brassica oleracea var. acephala)

1.3.2. Specific objectives

The specific objectives of the research study were:

1) To determine the effect of organic fertilizer (Farmyard manure) and inorganicfertilizers N:P:K (17-17-17) on growth and yield of collards.

2) To determine the effect of combined application of inorganic (N:P:K 17-17-17) andorganic fertilizer (Farmyard manure) on growth and yield of collards.

3

1.4. Hypotheses

To achieve the objectives, the following hypotheses were formulated:

1) Ho: There is no effect of organic fertilizer (Farmyard manure) and inorganic

fertilizers (N:P:K 17-17-17) on growth and yield of collards.

2) Ho: There is no effect of combined application of inorganic (N:P:K 17-17-17) and

organic fertilizer (Farmyard manure) on growth and yield of collards.

4

CHAPTER TWO

REVIEW OF LITERATURE

2.1. Overview of Collards

2.1.1. Origin and Botanical Description

The collard is a cool season crop that should be grown during early spring or fall. The

mature plant will withstand frosts and light to medium freezes. It is a cultivar of cabbage

(Brassica oleracea or Wild cabbage), and a member of the cabbage family (Brassica),

which is a genus of plants in the mustard family (Brassicaceae). Most people just refer to

them all as Cole crops or cabbages. Brassica plays a major role in the human diet (Sally,

2007). Like kale, cauliflower and broccoli, collards are descendents of the wild cabbage, a

plant thought to have been consumed as food since prehistoric times and have originated

in Asia Minor. From there it spread into Europe, being introduced by groups of Celtic

wanderers around 600 B.C. Collards have been cultivated since the times of the ancient

Greek and Roman civilizations. Collard greens dates back to the rate 17 th century in

United States (Fowke et al., 2006).

Collard greens are various loose-leafed cultivars of Brassica oleracea (Acephala Group),

the same species that produces cabbage and broccoli. The plant is grown for its large,

dark-colored, edible leaves. They are classified in the same cultivar group as kale and

spring greens, to which they are closely similar genetically. The name collard is a

shortened form of the word colewort "cabbage plant" (Sally, 2007).

The Cultivar Group name Acephala ("without a head" in Greek) refers to the fact that this

variety of Brassica oleracea does not have the usual close-knit core of leaves like

cabbage. The plant is a biennial where winter frost occurs, perennial in even colder

regions. It is also moderately sensitive to salinity. It has an upright stalk, often growing up

to two feet tall. The plant is very similar to kale. Plant Varieties, Carolina Improved

Heading (or Morris), Georgia Southern, Blue Max, or Heavy crop. These varieties have

consistently done well in North Carolina conditions. Popular cultivars of collard greens

include Georgia Southern, Morris Heading, Butter Collard (Korus , 2009).

5

2.1.2. Ecological requirement

Collards may be grown in a variety of soils. Heavier loamy soils will produce the greatest

yields. The lighter, well drained, sandy soils are best for early spring crops. Soils should

be well drained, rich in organic matter and have a pH of 6.0 to 6.5 (University of minisota,

2009) Leafy vegetables require quick, continuous growth for best quality. They need

ample nitrogen for good green color and tender growth. For average soils use 600 pounds

of 10-10-10 (or equivalent) fertilizer per acre (8 pints per 100 feet of row) before planting.

Side dress with 15 to 30 pounds of nitrogen per 3 to 5 weeks after the seed comes up or

after transplanting, and 2 to 3 weeks after that, (Delahaut, 1997). Collard is extremely

resistant to warm as well as cool temperature. Collards require full sun, and although they

can withstand more drought than the cabbage, (Sally, 2007).

2.1.2. Horticultural production field practices

a) Cropping Systems

There are four general ways to produce collards: Grow plants and set transplants in early

spring, and harvest the whole plant 50 to 60 days later. Grow plants and transplant in early

spring, and market cropped leaves in late spring, and carry plants over to fall when the

entire plant is harvested. Seed direct about August 15, or transplant from September 1 to

15, and harvest in late October to December. Seed direct to field in spring. These may be

harvested as leafy greens or thinned to 15 to 18 inches and carried over to fall. It requires

about 1 1/2 pounds of seed per acre (Sorensen, 1996).

b) Growing Plants and nursery arrangement

Plants may be grown by seeding directly in the field (1 to 2 pounds seed per acre) or in

protected beds (1 pound of seed per 1000 square feet). This should produce about 50 to 60

thousand plants or enough for about 4 to 5 acres. About 6 to 8 weeks will be required to

produce plants ready for transplanting (Sorensen, 1996).

6

c) Direct seeding

There are several good precision seeders on the market. In general, the seeders reduce seed

use by 40 to 70%. The stands are much more uniform and require very little thinning.

Uniform stands are easier to grow and harvest, thus reducing the cost of production.

Uniform stands grow evenly and are better weed competitors. Precision seeds that can be

used with collards include StanHay (belt type), Gaspardo and StanHay (vacuum type), and

Nibex (spoon type). Direct seeding can also be done with a Planet Jr., but requires more

seed and more thinning than stands established with precision seeders. Seed should be

placed in moist soil usually 1/2 to 3/4 inch deep, but never deeper than 1 inch. If adequate

moisture for germination is below 3/4 inch, irrigation should be applied. Frequent

irrigation is also important in obtaining good stands in hot weather (1/4 inch per day at

midday) (Delahaut, 1997).

d) Spacing

Spacing depends on how the crop will be produced. If the plants are to be cut when half

grown, they may be spaced 10 to 15 inches (25.4cm-38.1cm) apart. If they are to be

harvested when full grown they should be spaced 15 to 18 inches apart. If the seed is to be

drilled in the row and the young collard plants are to be harvested, similar to mustard

greens, the plants may be 2 to 4 inches apart. Rows should be 36 to 42 inches apart for

conventional systems. However, multi-row beds of 2 to 4 rows on 38 to 60 centers provide

greater yields and improved quality. In such a system, rows on each bed are spaced 12 to

18 inches apart. This provides rapid ground cover, fewer weeds and more tender growth.

(Delahaut, 1997)

e) Irrigation

Collards, like other members of this plant family, require above average moisture. Use

irrigation liberally in times of moisture stress, usually 1.5 inches per week when

precipitation is less than this. (Delahaut, 1997)

7

f) Weed management

The production method you use and the season you plant the crop will determine the kind

and extent of your weed problems. Chemical herbicides are available for use on collards

and are generally recommended. Whether you use an herbicide or not, some cultivation

will likely be necessary. Avoid deep cultivation. Close spacing and rapid growth will help

to suppress weeds (Delahaut, 1997).

g) Insect Management

Several worms (imported Cabbage worm, Cabbage looper, Diamond-back larvae) and

Harlequin bugs are the predominate insects. A rigid control program will be necessary,

especially during summer and fall. Aphids are also a serious problem during cool weather.

Use high pressure (200 psi) sprayers and a sticker to provide best control (Delahaut,

1997).

h) Disease Management

Some diseases like black rot are seed borne. You should insist on western grown,

chemically treated seed to reduce this disease. Another major disease is Downy Mildew

which produces discolored spots on the leaves. The Carolina variety has resistance to one

or more strains of Downy Mildew (Delahaut, 1997).

i) Harvesting

Harvesting may be done through: Cutting entire plants when very young, similar to

mustard greens (spaced 2 to 4 inches apart). Successive cutting can be done with these

systems. Cutting entire plants when about half grown (spaced 10 to 15 inches apart). And

they are tied in bunches of one to three plants with a rubber band, twisted or string;

Cutting entire plants when full grown (spaced 15 to 18 inches apart); Harvesting tender

leaves from full grown plants. When marketed these leaves are tied in one or two-pound

bunches. Check with your buyer to see how they would like the product packaged. Local

sales can often be made in bulk, but distant shipments and supermarket sales will have to

be placed in crates or cartons. Icing will also be necessary for quality maintenance

(Delahaut, 1997).

8

k) Cultivation and storage

The plant is commercially cultivated for its thick, slightly bitter edible leaves. They are

available year-round, but are tastier and more nutritious in the cold months, after the first

frost. For best texture, the leaves should be picked before they reach their maximum size,

at which stage the leaves will be thicker and should be cooked differently from the new

leaves. Age will not affect flavor. Flavor and texture also depend on the cultivar. Fresh

collard leaves can be stored for up to 10 days if refrigerated to just above freezing (1 °C)

at high humidity (>95%). In domestic refrigerators, fresh collard leaves can be stored for

about three days. Once cooked, they can be frozen and stored for greater lengths of time

(Delahaut, 1997).

2.1.3. Nutritional value of collard

Collard has mustard oil, sulphur and nitrogen containing compounds popular in fighting

Cancer. Their nutritional values exceed that of other known green vegetables. For

example; 100grams of collard contain; 85% water, 45calories energy and various minerals

such as 4.8grams, proteins 0.8grams fat, 7.5g carbohydrates, 250g calcium, 82mg

phosphorous, 1.5g iron, 43mg potassium, 9.300IU vitamin A, 0.16mg Thiamine, 0.31g

Riboflavin, 1.7mg Niacin and 1.52mg ascorbic acid (Lorenz & Maynard, 1980).

Table 1: Comparison of nutritional value between Collard and Cabbage

Nutritional value per

100 g of fresh yield

Collard greens

Nutritional value per 100 g of

fresh yield Cabbage,

Energy 151 kJ (36 kcal) 103 kJ (25 kcal)

Carbohydrates 7.1 g 5.8g

Fat 0.4 g 0.1g

Protein 3 g 1.28g

Vitamin A equiv. 575 μg (64%) 53μg (13%)

Vitamin C 26 mg (43%) 36.6mg (44%)

Vitamin K 623 μg (593%) 76(72%)

Calcium 210 mg (21%) 40mg (4%)

Source: USDA Nutrient database

9

2.1.4. Role and Potential of Collard Green in Health Promotion

Collards green are known to have a high cholesterol-lowering ability than all other

cruciferous vegetables such as: steamed kale, mustard green, broccoli, Brussels sprouts,

and cabbage in terms of its ability to bind bile acids in the digestive tract. When this bile

acid binding takes place, it is easier for the bile acids to be excreted from the body. Since

bile acids are made from cholesterol, the net impact of this bile acid binding is a lowering

of the body’s cholesterol level. It’s worth noting that steamed collards show much greater

bile acid binding ability than raw collards. We get unique health benefits from collard

greens in form of cancer protection. The cancer-preventive properties of collard greens

may be largely related to 4 specific glucosinolates found in this cruciferous vegetable:

glucoraphanin, sinigrin, gluconasturtiian, and glucotropaeolin. Each of these

glucosinolates can be converted into an isothiocyanate (ITC) that helps lower our cancer

risk by supporting our detox and anti-inflammatory systems (Ambrosone, 2009).

2.2. Effect of Fertilizers on Leafy Vegetables

2.2.1. Major or Macro-Nutrients

This group includes N, P and K which are required in maximum quantities by the plants.

These nutrients are often deficient in almost all the soils because of their heavy depletion.

The deficiency is corrected by the application of fertilizers based on soil analysis and crop

requirement (Rayar, 2004).

2.2.2. Functions of Macronutrients in Leafy Vegetables

a) Nitrogen

According to (Miller and Donahue 1990), Nitrogen is most often the limiting nutrient in

plant growth; it is a constituent of chlorophyll; plant proteins and nucleic acid. Nitrogen

can be utilized by plants as the ammonium cation or as the nitrate anion. It is then

involved in photosynthesis that is why an adequate supply of N is associated with high

photosynthetic activity, vigorous vegetative growth, and a dark green color. Excessive use

of Nitrogen in relation to other nutrients can delay crop maturity. Excess of Nitrogen can

lower the moisture content of grains at harvest, and causes weakening of cotton fiber and

cereal. (Amkha and Kazuyuki, 2006.)

10

b) Phosphorus

Phosphorus (P) does not occur as abundantly in soils as N and K. total concentration in

surface soils varies between about 0.02% and 0.10% .Unfortunately, the quantity of total P

in soils has little or no relationship to the availability of P to plants. P is the second most

often limiting nutrient. It is contained in plant cell nucleic and is part of energy storage and

transfer chemicals in the plants soils have low total and low plant-available phosphate

supplies because mineral phosphate forms are not readily soluble. P used by plants is taken

up as HPO42- and H2PO4

- anion. Unfortunately most soluble phosphates become fixed

(precipitated-form insoluble compound) before plants can absorb them. Organic

phosphates are important even major phosphate source in most soils (Miller and Donahue,

1990)

c) Potassium (K)

Potassium is one of essential nutrients required for plant growth and reproduction. It is

classified as a macronutrient as Nitrogen and phosphorus. It plays a vital role in

photosynthesis, carbohydrates transport, protein formation, control of ionic balance,

regulation of plant stomata and water use activation of plant enzymes and many other

processes (Munson et al., 1985)

d) Farmyard Manure (FYM)

Manure consists of animal excrement, usually mixed with straw or leaves. The amount and

quality of the excrement depend on the animals and feed. Good manure contains more

than just excrement and urine. According to FAO (1987), organic matter plays the

following roles: Improving soil structure; water infiltration and water retention; Improving

soil aeration and reduce the risk of erosion; in addition the organic matter has a buffer

effect that influences the variation of soil pH; Increasing the reserve of nutrients and

activating substances such as growth hormones; ( Parr and Hornic, 1995).

2.3. Effect of combine application of organic and inorganic fertilizer on leafyvegetable

Soil organic matter is the major reservoir of N and many other essential plant nutrients. It

is the main source of energy for soil organisms both plants and animals. The release of

Nitrogen from soil organic matter is controlled by soil micro-organisms.

11

During the decomposition of organic matter, soil microorganisms convert organic nitrogen

into ammonium (NH4+) and nitrate (NO3

-) forms of nitrogen which plants utilize. Its

combination with mineral fertilizer may increase vegetative growth. (Engel et al., 2001)

Organic manure supplies some nutrients for plants and the carbon containing compounds

are food for small animals and micro-organisms. Manures often improve the structure of

soils; they may do this directly through their action as bulky diluents in compacted soils or

indirectly when the waste products of animals or microorganism cement soil particles

together. These structural improvements increase the amounts of water useful to crops that

soil can hold, they also improve aeration and drainage and encourage good root growth by

providing enough pores of the right sizes and preventing the soil. (Cooke. 1967).

2.4. Time and Method of Fertilizer Application

Nitrogenous fertilizers must be applied in split, so that the Nitrogen loss through leaching

and washing could be reduced as Nitrogen being readily soluble and highly mobile is

subjected to these losses very easily. Therefore to achieve the highest recovery and

maximum use efficiency, it is essential that half of the total quality of the required

Nitrogen should be applied as basal and rest half in 2-3 split doses. Except in acidic and

highly alkaline soils, the Phosphorus must be applied in one dose as basal placement but in

acidic soils rock phosphate, bone meal or basic slay may be applied at least a fort right

before sowing or crop planting whereas in alkaline soils spraying of phosphate has given

better results.

The potassic fertilizers should be applied in single dose as basal placed but split

application along with N as top dressing has given better response in heavy soil types.

Sandy soil need split application of N for reduced loss of N through leaching. A

combination of organic manure and fertilizers is always beneficial for achieving highest

recovery and best fertilizer use efficiency (Miller and Donahue, 1990)

2.5. Composition of Farmyard manure

On average dry Farmyard manure contain about 2%N, 1.7% K and 0.4%P; but different

batches may contain very different percentages of nutrients depending on the origin and

storage. (Berryman, 1965)

12

2.6. Fertilizer recommendations on collards, kales, cabbage and other related foddercrops.

Practically in all experiments, collard, kales and cabbage responded well to nitrogen and at

least 50 kg N/ha are justified. It does not matter whether the N fertilizer is applied at

transplanting or a later top dressing, 50 kg of P2O2 and 50 kg of K2O are also

recommended respectively per hectare. There is little information on the Phosphorus and

potassium fertilization of these crops grown on average land, but they contain considerable

amounts of both P and K and these plant foods should be applied as fertilizers before

transplanting. Thus 300 kg/ha of N: P: K 17-17-17 compound fertilizer without farmyard

and 150 kg of N: P: K 17-17-17 with farmyard is respectively used assuming that 20t/ha of

farmyard manure only is used per hectare. (Cooke, 1972)

14

CHAPTER THREE

MATERIAL AND METHODS

3.1. The experimental site

This study was conducted at crop production research and demonstration field, ISAE Busogo,

Northern Province, Rwanda. The altitude of this region is 2200m above sea level and receives

four seasons well established throughout the year. Such seasons are: Short rainy season: It

covers the period between September and December; Short dry season: Starts around mid-

December and lasts till February; long rainy season: It covers the period ranging from March

to June; long dry season: It starts from June to September. (MINALOC, 2006). This region is

known to have annual rainfall of 1400 mm, with an average temperature of 13oC and relative

humidity of 86%

Table 2. The Climatic Data during the Experimentation

Months AverageTo

(oC)

Max.To( oC) Min.To (oC) Rainfall

(mm)

Humidity %

June 15.2 21.0 10.0 78.3 84

July 15.0 21.8 8.3 28.5 78

August 15.3 20.7 10.7 107.4 81

September 15.3 21.8 10.4 228.3 88

October 15.7 20.8 10.5 167.6 87

Source: ISAE station, 2011.

Busogo soil is permeable and generally it is fertile (MINALOC, 2006). The soil is of

volcanic type and is classified into Andisol. According Raymond, (1990) Andisols are

formed from volcanic ejecta (ash), characterized by loose and well aerated physical status.

The results of soils analysis of the experimental plots have shown that the soil could be

classified into fairly (weak) acidic soil. The average pH value recorded before trial was 5.83

and after trial, it was found to be 5.79. This area was chosen due to the fact that the area is

composed of organic soils which are fertile and where the vegetables are mostly grown

specially Brassicaceae.

15

3.2. Experimental Design and Treatment Application

The experimental design was randomized complete block design (RCBD) with 4 treatments

and each replicated three times. Total plots: 4 x 3=12 plots. Plot size was 1.5 m x1.5 m=2.25

m2. Thus the experimental field was 2.25 m2x12= 27 m2. As shown in the figure below, the

plots were separated with the paths of 0.5 m, between replications and 0.5 m between

treatments. Thus the total plots of experiment were 41.25 m2 and 1 m of borders was provided

around the experiment field on which cabbages were grown. The following treatments were

applied: Treatment 1: control; Treatment 2: 10 t/ha of FYM +150 kg /ha of N: P: K (17-17-

17); Treatment 3: 20 t/ha of FYM only; Treatment 4: 300 kg of N: P: K (17-17-17)/ha. Using

this rate, I based on the recommendation reported by (Cooke, 1972) and (Gupta, 1990).on

vegetables in the same family.

Figure 1: Experimental layout

T1 T3 T4 T2Block1

T3 T4 T2 T1

T4 T2 T1 T3

Block2

Block3

1.50 m

0.50 m

0.50m

1.50

m

16

Key:

T1 ═ Control;

T2 ═ 150 kg/ha of N: P: K 17-17-17 + 10t/ha of FYM;

T3 ═ 20t/ha of FYM;

T4 ═ 300 kg/ha of N: P: K 17-17-17

3.3. Planting Materials

The plant to be used was collards (Brassica oleracea var. acephala) of Brassicaceae family,

known to be highly adapted and productive in the similar conditions. The choice of this

vegetable was due to its nutrient value; adaptability and short vegetative cycle.

3.4. Soil and Manure Nutrient Analysis

The farm yard manure (FMY) used in this experiment was obtained from ISAE farm.

Farmyard manure content was 1.5% nitrogen, 0.44% of phosphorus and 1.25% of potassium.

The Farmyard which was used is 20 t/ha reported to 4.5 kg /plot of 2.25 m2 has been applied.

3.5. Mineral fertilizer (N: P: K 17-17-17)

The mineral fertilizer used is N:P:K 17-17-17, a mixed fertilizer which contains 17 kg of

nitrogen, 17kg of phosphorus and 17 kg of potassium in 100 kg of total compound. It is an

important mixed fertilizer for plants and vegetables growth in general and it is available in the

market (MINAGRI, 2010). In addition, the rate of 300 Kg/ha of N: P: K equivalent to 67.5 g

/2.25 m2 has been respectively applied.

3.6. Other materials

To carry out cultural farming practices like tillage; sowing, transplanting, weeding, and the

data collection, the following materials were used: hoe for cultivation, graduated ruler for

taking height and leave size measurements, electric weighing sensitive balance to measure the

weight of fertilizers and yield, the diameter to measure the size of plots, the stake to limit the

plot, rope bags and baskets to transport the farmyard manures, micrometric screw gauge to

measure stem diameter, oven to dry the harvested leaves. Leaf area for collards was taken

once at the 25thday after transplanting and it was determined, using the following formula:

green collard leaf area = (Length x Width) (0.67) as it was reported by Pearcy et al. 1989.

17

Leaf length was measured using a tape measure, beginning at the leaf blade-petiole intercept

to the leaf tip. The width was measured at the widest leaf lobes. Leaf length and leaf width

measurements were taken from a randomly selected 5th- leaf from the shoot tip.

3.7 Nursery bed preparation and sowing

Before I start my research, nursery bed preparation and sowing was done. The nursery was

prepared at 13th July 2011 by removing plant residues, breaking bigger soil particles. At the

same Certified seeds of collards bought from AGROTECH and were raised in the nursery 1

month before transplanting and watered once a day until the seedlings were ready to be

transplanted

3.8. Land Preparation and Treatment application

The land was ploughed by breaking the soil to achieve favorable tilth. The primary was done

on 13th July 2011 by removing plant residues, breaking bigger soil particles and taking needed

dimension. The second tillage was done on 12th August 2011 for making the soil suitable for

seed germination. Land plotting was carried out by respective plot size; this was followed by

labeling plot using pieces of wooden plank. After the soil unit was determined, the soil

samples were collected from the soil unit. This soil sample would be representative of that

soil unit. According to Dilip (1996): Soil is a heterogeneous body, so, if sample is collected

from only one spots of the soil unit, it would not represent it. To have the representative

value, the samples should be collected from several spots of the soil unit. Farmyard manure

with 20 t/ha and 10 t/ha from ISAE-farm was applied before transplanting in respective plots

(as shown on the design of experiment) and mixed with the soil using hand hoe. The mineral

fertilizers (N: P: K 17-17-17) with 150 kg/ha and 300 kg/ha were respectively applied in

treatment two and in treatment four at the time of transplanting. In some plots organic matter

and mineral fertilizer were applied separately while in others, they were combined

respectively with 10 t/ha of farm yard manure and 150kg/ha of N:P:K to evaluate their effect

on growth and yield of collards at the end of experiment.

3.9 Transplanting

After seedlings were ready to be transplanted, they were approached and healthy seedlings

were selected among others to be transplanted in rows spaced with 37cm and 37 cm between

(37 cm x 37cm). The seedlings were put into the holes made within the lines at the rates of 1

18

seedling per holes. Thus 16 Plants per plot. This means 16 x 12= 192 plants in the whole

experiment

3.10 Routine Management Practices

a. Weeding and Crop protection

Weeding control was done two times during the research time in 3rd and 6th weeks after

transplanting by using hands in order to allow water infiltration and aeration to the soil and

eventually keep the plants from weeds competition and make the field always clean. During

the young stage of the plant, insecticide “dethane” was used to control cut worms (Agrotis

Segitum).

3.11. Data Collection

3.11.1. Soil Sampling

Soil testing was known for a long time as one of the possible means for the determination of

fertilizer application rates. The logic behind this approach is that a soil contains enough

amounts of nutrients from a fertilizer application that can be reduced or increased. The need

for using soil tasting data for the determination of fertilizer application rates has become more

necessary. The continued uses of heavy doses of fertilizers have resulted in a high

accumulation of plant nutrients, particularly phosphate and potassium (Zulkifli et al., 1994).

Soil sampling was taken carefully in each plot before and after experiment at the 30 cm deep

top soil on plot basis. Five locations were selected in each plot. The equal portion of soil from

these 5 samples in each plot were taken and mixed for making a composite sample of 0.5 kg

that were representative for each plot. The composite samples were used in analysis for each

treatment.

The number of samples was one before field experiments and twelve after field experiment

which were analyzed in ISAE laboratory.

Figure 2: Sampling points in experimental plot.

* *

*

* **

19

Before laboratory analysis, the collected samples were air dried and then sieved with 2x 0.5

mm diameter sieve in soil laboratory of ISAE. The following chemical analysis was carried

out: Concentration of total nitrogen using KJELDHAL method, available phosphorus by

DICKNAN- BRAY method, available potassium using Cobalinitry method and the pH of soil

using pH meter.

3.11.2. Agronomic Parameters Measured

The parameters which were measured include:

Height of plants, this was recorded at the 15th day after transplanting and later during each

harvesting within interval of 7 days, it means respectively at 25th day, 32nd day, 39th , 46th day

and 53rd day after transplanting. To take the plant height, a ruler was used; the height was

taken from the soil level up to the youngest leave of plant.

Number of leaves was taken once at the 25th day by accounting each leaf from the bottom to

the top. Leaf area was another parameter to be recorded, this was recorded using also a

graduated ruler to take a leaf length and a leaf width then later leaf area was calculated using a

formula reported by Pearcy et al. 1989

Weight of fresh leaves was recorded at each harvesting. As harvesting was progressive at least

the three leaves were left to allow photosynthesis to remaining plant after fresh weight of

edible leaves were taken using electric weighing sensitive balance. Weight of oven-dry mass

of edible leaves was taken after drying the harvested leaves at 105oC for 10 hours.

Stem diameter was taken six times from the 15th day after transplanting up to the last

harvesting in order to evaluate the plant growth. To record this parameter a micrometric screw

gauge was used.

3.11.3. Statistical Analysis

The data collected were arranged in Microsoft excel and later subjected to analysis of

variance using JMP 5.1 computer software The treatments with significant means were

separated using Turkey HSD method for pair use comparison.

20

21

CHAPTER FOUR

PRESENTATION AND INTERPRETATION OF RESULTS

4.1. Effects of organic and inorganic fertilizers on soil chemical properties after

transplanting of collards

The observation gathered during laboratory experiments for determination of soil chemicals

properties are given in the appendix 8and the following table 3 indicates the means of soil

chemical observed after the experiment according to the applied treatments in the experimental

design. This shows also the effect of fertilizers on soil pH; Nitrogen; Phosphorus; Potassium;

Carbon; Organic Matter; and Carbon Nitrogen ratio after transplanting of Collard.

The single sample before the trial was taken by taking the four representative samples in four

corners of the field and one sample in the middle. These were mixed to have one representative

sample before transplanting. The results of pH-water observed, were 5.83 before experiment and

after harvesting, it was ranging from 5.76 to 5.82 and they were not significantly different each

other. The high mean was 5.8 and the highest value was observed in treatment subjected to the

combination of N: P: K and farmyard and treatment treated with farmyard only. The lowest

value was observed in the control. The concentration of total nitrogen in the soil of the

experiment site after harvesting was not significantly different with the high mean of 0.30%.

The value of available phosphorus before transplanting was of the average of 29.92 ppm. The

values of available phosphorus after harvesting were significantly different at p≤ 0.05 with the

range of 54.1 ppm to 22.1 ppm. The high mean was observed in treatment treated with farmyard

manure followed by the treatment subjected to the combination of N: P: K and farmyard. The

low mean was observed respectively in the control and treatment subjected to N: P: K, which

was not significantly different, each other. The treatments subjected respectively to N:P:K and

Farmyard were significantly higher in potassium content with high mean of 1.14meq/100g and

low means were in treatments treated with N:P:K and Farmyard with the low mean of 0.34

meq/100g. The potassium value before transplanting was 0.78 meq/100g.

The soil organic carbon concentration was 2.7% before transplanting and after harvesting, the

high mean of 2.9 % was observed in treatment with Farmyard manure.

Other treatments were not significantly different at p≤ 0.05 with the low mean observed in

treatment subjected to N: P: K (17-17-17). The effect of fertilizers on organic matter has shown

22

significant difference in all treatments with the high mean of 5% in treatment with Farmyard

manure while the exception was observed in treatment subjected to N:P:K application. The

average before transplanting was of 4.65% there. However, there was no significant difference

observed in carbon nitrogen ratio. The average value before transplanting was 11%

Table 3: Effects of organic and inorganic fertilizers on soil chemical properties aftertransplanting of Collard

pH Nitroge

n (%)

Phosphorus

(ppm)

Potassium

(meq)

Carbon

(%)

organic

matter(%)

C/N ratio

(%)

Control 5.76a 0.21a 22.1c 0.42bc 2.5ab 4.3ab3 12.4a

N:P:K

& FYM

5.8a 0.28a 43.7b 1.03a 2.7ab 4.7ab 10.5a

FYM 5.8a 0.30a 54.1a 1.14a 2.9a 5.0a 9.6a

N:P:K 5.79a 0.26a 30.3c 0.97ab 2.4b 4.2b 10.0a

*Means followed by the same letters are not significantly different according to Turkey HSD

at P ≤ 0.05

4.2. Effects of organic and inorganic fertilizers on plant height of Collard (cm)

The effect of different fertilizers on plant height varied with time. At 15 day after transplanting,

the plants which was treated with N:P:K was significantly taller with the mean height of 14.6 cm

at p≤ 0.05 while those subjected to farmyard manure alone and the combination of farmyard

manure and N:P:K followed with identical mean of 12.0 cm and 12.3 cm respectively upon

analysis. However, plants treated with farmyard manure and the control was not significantly

different at p≤ 0.05. In addition, it was observed that plants treated with N: P: K was

significantly higher by 40% compared with the control. The plants subjected to N: P: K,

farmyard manure and combination of both farmyard manure and N: P: K was not significantly

different from each other except the control at 25th and 32nd day after transplanting.

However, at 39th day after transplanting, the plants that were treated with N: P: K and the

combination of N: P: K and farmyard manure were significantly higher by about 31.5%

compared with the control at p≤ 0.05. The plants that were subjected to N: P: K, farmyard

23

manure and combination of both farmyard manure and N: P: K was the same in mean plant

height except for the control which significantly lower at 46th and 53rd day after planting.

Table 4: Effects of organic and inorganic fertilizers on plant height of Collard

15th day 25th day 32nd day 39th days 46th day 53rd day

Control 10.4c* 14.2b 18.0b 19.1c 20.0b 21.6b

N:P:K and FYM 12.3b 17.5ab 21.3ab 23.3ab 25.1a 27.8a

FYM 12.0bc 16.53ab 20.0ab 21.3bc 24.4a 27.7a

N:P:K 14.6a 21.0a 24.0a 25.1a 26.3a 29.0a


at P ≤ 0.05.

4.3. Effects of organic and inorganic fertilizers on number of leaves of Collard

The number of leaves has been recorded twice. The first record was done at the 15 th day after

transplanting and the second at the 25th day to determine the effect of organic and inorganic

fertilizers on their number during the plant growth (Appendix 11; 12; 37 and 38) and the

following Figure 3 shows that there was no significant difference between treatments

according to Turkey HSD at P ≤ 0.05.

a* a a a

10.1a a aa

0

5

10

15

Control NPK&FYM FYM NPK

Pla

nt h

eigh

t (cm

)

Treatments

15th day25th day

Figure 3: Effects of organic and inorganic fertilizers on number of leaves of Collardafter 15th and 25th day

24

4.4. Effects of organic and inorganic fertilizers on stem diameter (mm) of Collard

The means comparison of stem diameter of collard showed that the effects of organic and

inorganic fertilizers on stem diameter were not significantly different in all treatments from

the 15th, 25th day up to 32nd day after transplanting at p ≤ 0.05. The exception concerns the

treatments subjected to the combination of both N: P: K and farmyard manure, which showed

increasingly high means of 11.1 mm, 19.6mm and 20.3mm. The plants subjected to farmyard

manure, and the combination of both N: P: K and farmyard were not significantly different at

the 39th day after transplanting. The significant difference was observed in the treatment with

N: P: K by about 10 % compared to the control. The treatments of the combination of N: P: K

and Farmyard manure, farmyard manure alone and N: P: K did not show any significant

difference from the 46th day up to the 53rd day after transplanting. The highest effect was

given by the combination of N: P: K and Farmyard manure by 23.6% compared to the control

at 46th day and by 15.7% compared to the control at the 53rd day. However, the difference was

observed in the control at the 46th day after transplanting.

Table 5: Effects of organic and inorganic fertilizers on stem diameter (mm) of Collard

15th day 25th day 32nd day 39 days 46th day 53rd day

Control 7.6b* 14.3b 14.5b 17.5c 19.0b 21.3a

N:P:K and FYM 11.1a 19.6a 20.3a 20.2a 23.5a 24.6a

FYM 8.0b 14.0b 16.6b 20.1ab 22.2a 24.1a

N:P:K 8.4b 15.1b 17.8ab 19.3bc 22.2a 24.3a


at P ≤ 0.05

4.5. Effects of organic and inorganic fertilizers on leaf area (cm2) of Collard

The leaf area was recorded at the first harvesting after transplanting to determine the effects of

organic and inorganic fertilizers on leaf area of Collard (Appendix 13 and 45). The treatments

with N: P: K and the combination of both N: P: K and farmyard manure did not show

significant difference. The widest leaf area was observed in plants subjected to the

combination of both N:P:K and farmyard manure with the high mean of 397.2 centimeters

25

square which was 77% higher compared to the control. It was followed by the mean of 355.3

cm2 from the treatment subjected to N: P: K. However the great significant difference was

noted with the plants within treatments in the control and farmyard manure. The leaf area of

plants with Farmyard manure is wider by about 24% compared to the control.

c*

a

b

a

0

50

100

150

200

250

300

350

400

450

Control NPK and FYM FYM NPK

Leaf

are

a in

cm

squ

are

Treatments

25th day

Figure 4: Effects of organic and inorganic fertilizers on leaf area (cm2) of Collard

4.6 Effects of organic and inorganic fertilizers on Fresh weight (grams/plant) of Collard

The fresh leaves were weighted after each harvesting to determine the yield of these fresh edible

leaves in all harvesting intervals. The effects of organic and inorganic fertilizers on fresh weight

of collard varied with time. At the 25th day after transplanting, it was observed that the plants

subjected to the combination of N: P: K and farmyard manure were significantly heavier with the

high mean of 722.8 grams/plant at p ≤ 0.05. It was observed that plants treated with the

combination of N: P: K and farmyard was significantly higher in weight by 102 % compared

with the control. There is no significant difference between the plants under treatments of the

combination of N: P: K and Farmyard manure and plants with N: P: K. the plants subjected to

the Farmyard manure were significantly heavier by about 42% compared to the control.

However, at the 32nd day after transplanting, the plants treated with N: P: K and farmyard was

significantly heavier by about 97.5% compared to the control p ≤ 0.05. During all the period of

experiment, the plants that were subjected to N: P: K and farmyard manure were the same in

26

means of leaf weight except for the control, which significantly lowered. Observing the Table 6

below, it is clear that N:P:K+FYM and N:P:K alone were significantly higher in comparison

with the fresh yield weight from FYM alone and the least mean was observed from the control

upon analysis from 39th , 46th and 53rd days after transplanting However, It has been observed

that the plant under the combination of N: P: K and Farmyard manure were the heaviest with the

identical high means of 542.3g; 552.0g; 816.7g respectively at the 39th day; 46th day 53rd day

after transplanting.

Table 6: Effects of organic and inorganic fertilizers on Fresh edible yield of Collard

25th day 32nd day 39 days 46th day 53rd day

Control 356.2c* 256.7c 222.8c 234.3c 402.6c

N:P:K and FYM 722.8a 507.0a 542.3a 552.0a 816.7a

FYM 505.8bc 356.0b 371.1b 428.9b 569.6b

N:P:K 585.0ab 404.0b 465.1ab 480.9ab 758.8a

*Means followed by the same letters are not significantly different according to Turkey HSD at

p≤ 0.05.

4.7 Effects of organic and inorganic fertilizers on oven-dry mass of edible leaves of

Collard

The oven-dry mass of edible leaves was taken again after each harvesting to determine the yield

of these edible leaves after all experiment. The effects of organic and inorganic fertilizers on dry

mass of collard also varied with the time. Observing the Table 7. below, it was noted that the

treatments subjected to the combination of N:P:K and Farmyard manure have got the highest

means during the time of trial in increasing manner with the high mean of 494 g/plant at the 53rd

day after transplanting. This has been followed by the treatment with N: P: K only in addition it

has been observed that there was no significant difference between the treatments with

combination of both N: P: K and Farmyard manure and the one with N: P: K only at P ≤ 0.05

from 25th day up to the 53rd day after transplanting. The plants subjected to the Farmyard manure

were significantly heavier by about 30.9% compared to the control and significantly lower by

69.8% from the leading treatment at P ≤ 0.05.

27

Table 7: Effects of organic and inorganic fertilizers on oven-dry mass of edible leaves ofCollard

25th day 32nd day 39 days 46th day 53rd day

Control 162.0c* 116.2c 100.4c 121.3c 222.3b

N:P:K and FYM 398.4a 305.0a 327.7a 321.4a 494.3a

FYM 231.6bc 155.2bc 164.8bc 191.3bc 291.1b

N:P:K 298.5ab 213.4b 242.6ab 232.5ab 378.9ab

*Means followed by the same letters are not significantly different according to Turkey HSD at

p≤ 0.05.

4.8 Effects of organic and inorganic fertilizers on Total fresh weight and Total oven-dry

mass of Collard

The effect of Fertilizers on fresh edible leaves weight varied significantly in all treatments,

thus the treatment subjected to the combination of both N: P: K and farmyard manure showed

significantly high mean of 223.0 t/ha. This was followed by the treatment under N: P: K with

the mean of 191.7t/ha. In addition, the high mean was significantly higher by about 113%

compared to the control. However the figure 5; 6; 7 and the appendices 49, 50,51and 52

demonstrated that either in total fresh weight or in total oven-oven dry weight, the plants

within treatments treated with the combination of both N:P:K and Farmyard were

significantly different and heavy compared to other treatments. The plants under N: P: K

treatment followed in all cases followed by the plants subjected to Farmyard manure, while

the control lowered in all considerations as it is shown in the Table 8 bellow. Guertal and

Edwards (1996) reported fall collard yields of 10,400 – 14,700 kg /ha if harvested once using

various mulches, and Mulvaney MJ 2006, reported that the Collard yield averaged 23,109 ±

6411 kg /ha (standard deviation) if harvested once, so the yields in this study are within the

expected range for the area.

13

d*

a

c

b

d

a

cb

0

500

1000

1500

2000

2500

3000

3500

Control FYM andN:P:K

FYM N:P:KFertilizers

Fres

h ed

ible

yie

ld g

/pla

nt

Freshedibleyield ingrams/plant

Oven-drymass ofedibleyield ingrams/plant

Figure 5: Effects of organic and inorganic fertilizers on total fresh weight and totaloven-dry mass of Collard (in grams).

d*

a

c

b

d

a

gb

0

50

100

150

200

250

Control FYM and N:P:K FYM N:P:K

Yie

ld in

T/h

a

Total freshedible yieldin t/ha

Total oven-dry mass ofedible yieldin t/ha

Fertilizers

Figure 6: Effects of organic and inorganic fertilizers on total fresh weight and totaloven-dry mass of Collard(T/ha).

14

d

d

a

a

c

c

b

b

0

50

100

150

200

250

Yie

ld in

T/h

a

Control FYM andN:P:K

FYM NPK

Treatments

Total freshbiomass in inT/haTotal oven-dry biomass inT/ha

Table 8: Effects of organic and inorganic fertilizers on total fresh biomass and totaloven-dry biomass of Collard (in T/ha).

13

CHAPTER FIVE

DISCUSSION

5.1. Effects of organic and inorganic fertilizers on soil chemical properties after

transplanting of collards

The results of pH-water observed after transplanting were ranging from 5.76 to 5.82 with

the highest value of 5.8 in the Treatments subjected to the combination of N: P: K and

farmyard and in the one treated with Farmyard only. The lowest value was observed in the

control. According to the interpretation standards established by Mutwewingago and

Rutunga (1987), the soil of the experimental site range in fairly acidic soil. (pH 5.2-6.2).

In this study, the decrease of pH value from 5.83 to 5.76 has been influenced by the

decomposition of existing organic matter because organic matter in form of plant litter,

compost, and manure will decrease soil pH through the decomposition.(Brady and Well

2002).

The total Nitrogen content varied from 0.21% to 0.30% after transplanting with the

average of 0.23 % before transplanting. According to interpretation standards of total

nitrogen established by Mutwewingago and Rutunga (1987), this soil nitrogen content is

between 0.2-0.5 percent which high class is. The increase was observed respectively in

treatments subjected to Farmyard manure, combination of both N: P: K and farmyard

manure and N: P: K only. This may resulted to mineralization of organic matter and due to

the application of nitrogen-containing fertilizers (20t/ha of FYM; 150 kg of N: P: K /ha +

10 t/ha of FYM; and 300 kg of N: P: K /ha as it was reported by Palm and al., (2000).

According to Raymond and al, (1990), organic matter is the major source of total nitrogen

into the soil (90 to 95%).that is why the nitrogen rate increased in the soil as Farmyard

manure is increased into the soil.

It was observed also that the treatments received Farmyard manure, the combination of

both Farmyard manure and N: P: K and N: P: K only showed the variation in available

Phosphorus from 29.92 ppm to be respectively: 54.1, 43.7 and 30.3 ppm while it reduction

from the control. The data of available phosphorus in this experimental site ranged

between 20 to 50 ppm. According to Mutwewingago and Rutunga (1987), this soil is in

the category of moderate available phosphorus except in the treatment that received

Farmyard manure only which was found in high availability of phosphorus upon soil

14

analysis. The increase in available phosphorus may be caused by decaying plant and

animal residues, humus, and microorganisms as it was reported by Steven and Hodges

(2002). The combination of organic source of Phosphorus and inorganic Phosphorus, can

lead to the release of Phosphorus by mineralization of organic matter. These results are not

far from the one found by Nyirarukundo (2011) under Busogo conditions where high

value in available Phosphorus resulted from the accumulation of organic matter and

decomposition released high quantities of Ca from organic matter and increased

availability of Phosphorus. Steven C. Hodges (2002)

The results obtained on soil potassium showed that the soil potassium content was 0.78

meq/100g of soil and varied from 0.42 meq/100g to 1.14/100g of soil. The treatments

treated with Farmyard manure and the one with the combination of both N: P: K and

Farmyard manure showed high mean followed by the treatment with N: P: K only whereas

the control decreased. Potassium does not move readily in most soils especially in soil

enriched in organic matter. However, on sandy soils with low CEC, potassium can move

by mass flow, and loss from the surface soil can be significant, especially after periods of

heavy rainfall. That is why we may say that the decrease of potassium in the control and in

the treatment subjected to farmyard manure is due to low amount of organic matter and

thus high rate of leaching. Another reason can be explained by high rainfall level

experienced during the experiment. This was stated by Steven C. Hodges (2002) that the

Loss of K is minimized by implementing good erosion control practices; maintain good

soil pH to increase soil CEC, building soil organic residues where possible, and using split

applications to reduce leaching losses on soils with low CEC. In addition, This is was due

to the addition of potassium-containing fertilizers whereas it decreased in the control

because of excessive use of K by the crop as was reported by Steven C. Hodges (2002)

that the availability of soil potassium depends primarily on the types and amounts of soil

minerals present in the soil and the absorption of the crop. According to Mutwewingago

and Rutunga (1987), the data were ranging between 0.6-1.2 which is in category of high

availability of potassium.

The results from soil analysis showed also that the average of organic carbon was 2.7%

before transplanting while the high value was observed in treatments treated with

farmyard manure. The range was between 2.4% and 2.9%. According to Henry et al.,

15

(1997), long term application of organic manure is expected to increase organic carbon

and humus content of the soil. Therefore the increase in organic carbon was due to

decomposition of farmyard manure which was buried during ploughing. In addition it has

been observed that the high value of Carbon to Nitrogen ratio was high in the control and

low in treatment with Farmyard manure with the range of 9.56% and 12.35% after

transplanting. According to Tom and Nancy (1996) the higher the C/N ratio the lower will

be the mineralization thus the experimental site was in quick mineralization category

according to the norms of Mutwewingago and Rutunga (1987).

5.2. Effects of organic and inorganic fertilizers on plant height of Collard in cm

The results observed in this study indicated that the height of collard at different stage of

growth was highly influenced by treatments. At 15th day after transplanting there was

significant difference between treatments with the highest mean of 14.6 cm in treatment

subjected to N:P:K followed respectively with the combination of both N:P:K and

Farmyard and the treatment of Farmyard. The height response to fertilizers was due to

nitrogen amount which is responsible for shoots and leaf growth. The soil potassium is

also important in the breakdown of Carbohydrates, in the process which provides energy

for plant growth as reported by Gupta, (2004). A good supply of Nitrogen is associated

with vigorous growth and a deep green color whereas the plants deficient in N become

stunted and yellowing appearance (Steven and Hodges 2002).The last one was observed in

the control, where no fertilizer was applied, this was due to the lack of nutrients required

by the plant. During 25th; 32nd; 39th; 46th; 53rd day after transplanting, the plants subjected

to N: P: K, combination of both N: P: K and Farmyard manure, and Farmyard manure

alone were not significantly different in terms of height. This response of plants height to

the fertilizers may the consequences of availability on macro elements in the soil and thus

high photosynthetic activities as it was explained by Miller and Donahue (1990), who

stated that the soil reaction affect the plant growth by applying mineral fertilizer. By using

farmyard manure, nutrients content of the soil are improved and microbial activity of

decomposing and mineralization of applied Farmyard manure get enhanced and this leads

to release of plant nutrients which influence plant growth and yield in general.

5.3. Effects of organic and inorganic fertilizers on number of leaves of Collard

16

The mean numbers per plant was from 6.4 to 7 at the 15th day which shows that there was

no significant difference upon analysis at P ≤ 0.05. The identical means also were found at

the 25th day eventually with high means in plants within in the treatments subjected to N:

P: K.. Here also the explanation which may be given by the fact that the plots receiving a

combination of organic and inorganic fertilizers produced slightly higher number (P>0.05)

is that Nitrogen is involved in photosynthesis. That is why an adequate supply of Nitrogen

is associated with high photosynthetic activity and vigorous vegetative growth (Miller and

Donahue1990).

5.4. Effects of organic and inorganic fertilizers on stem diameter of Collard

The means comparison of stem diameter has shown that the combination of both N: P: K

and Farmyard manure were significantly higher in all treatments from the 15th, 25th day

up to 32nd day whereas other treatments were not significantly different could be due to

effect of potassium which is responsible of both growth and size of the stem as explained

by Munson et al., (1985) and cited by El-Sirafy et al., (2008). During the decomposition

of organic matter, soil microorganisms convert organic nitrogen into ammonium (NH4+)

and nitrate (NO3-) forms of nitrogen which plants utilize. Its combination with mineral

fertilizer may increase vegetative growth (Engel et al, 2001). At the 39th day; 46th day;

and 53rd day both treatments with the combination of N: P: K and farmyard manure and

the one with farmyard manure only were not significantly different each other and were

the best in terms of stem diameter. This is due to the quick mineralization of organic

matter, which leads to the release of macro elements and thus increases in stem growth. It

was also seen that at the 53rd day after transplanting the plants had the identical means

although the high mean was in the treatment under combination of organic and inorganic,

this is because the plant had attained their optimum growth in terms of stem diameter.

17

5.5. Effects of organic and inorganic fertilizers on leaf area of Collard

The data recorded at the first harvesting after transplanting to determine the effects of

organic and inorganic fertilizers on leaf area of Collard, showed that the treatments with

N: P: K and the combination of N: P: K and farmyard manure did not show significant

difference thus the widest area was observed in plants subjected to the combination of

both N: P: K and farmyard manure with the high mean of 397.2 centimeters square. This

mean is significantly higher by about 77% compared to the control. It is followed by the

mean of 355.3 cm2 from the treatment subjected to N: P: K. This variation might be due to

the availability of nutrients especially nitrogen and could be due to the improvement of

soil water holding capacity as mentioned earlier by Roe and Cornforth (2000).

Furthermore, organic manure activates many species of living organisms, which release

phytohormones and may stimulate the plant growth and absorption of nutrients (Arisha et

al., 2003). Such organisms need nitrogen for multiplication. This is possible reason that

the use of organic manure with inorganic fertilizer showed a beneficial effect on leaf area.

However the decline may be associated to low nitrogen content in the control. This has

been stated by Steven and Hodges (2002).

5.6. Effects of organic and inorganic fertilizers on Fresh and oven-dry mass of edible

leaves of Collard

The results of this study indicate that both Fresh and oven-dry mass of edible leaves of

Collard responded much stronger to the combination of both N: P: K and Farmyard

manure levels than N: P: K alone or Farmyard manure alone Negative effects of excessive

application of N on biomass production was documented for several crops (Robert et al.,

1989), including Brassica oleracea L. var. Acephala. (Chweya, 1997). Nkoa et al., (2003),

suggest that biomass reductions caused by excessive N applications may be the result of

osmotic imbalances due to N accumulation in plant tissues. In addition the decline in

treatments subjected to Farmyard manure and in the control can be justified by low

amount of N: P: K rate in the soil. These either fresh or oven-dry mass of edible leaves

were relatively in concordance with the results of leaf areas found above.

18

5.7. Effects of organic and inorganic fertilizers on Total fresh weight and Total oven-

dry mass of Collard

The effect of Fertilizers on fresh edible leaves mass has varied significantly in all

treatments, thus the treatment subjected to the combination of both N: P: K and Farmyard

manure showed significantly high mean of 223.0 t/ha. This was followed by the treatment

under N: P: K with the mean of 191.7t/ha. In addition, the high mean was significantly

higher by about 113% compared to the control. However the appendix 49; 50; 51 and 52

demonstrated that either in total fresh weight or in total oven-dry weight, the plants within

treatments treated with the combination of both N: P: K and Farmyard were significantly

different and heavy compared to other treatments. The plants under N: P: K treatment

followed in all cases followed by the plants subjected to farmyard manure, while the

control lowered in all considerations as it is shown in the table The plants under N:P:K

treatment followed in all cases followed by the plants subjected to Farmyard manure,

while the control lowered in all considerations as it is shown in the Table 8. Guertal and

Edwards (1996) reported fall collard yields of 10,400 – 14,700 kg /ha if harvested once

using various mulches, and Mulvaney, 2006, reported that the Collard yield averaged

23,109 ± 6411 kg /ha (standard deviation) if harvested once, so the yields in this study are

within the expected range for the area. In addition, the results in terms of growth and yield

are in accordance with those obtained by Shiralipour and Faber (1996) on broccoli

(B.oleraceavar Italica); Wong et al. (1990) and Magnusson (2002) on chinensis cabbage

(B. chinesis) and Abdelrazzag (2002) on onion (Allium cepa). The highest yield of leaves,

fresh and dry weights of collards were obtained by application of 10toness/ha of Farmyard

manure with 150kg/ha of inorganic fertilizer (N:P:K). This variation was due to the

availability of nutrients especially nitrogen and potassium and could be due to the

improvement of soil water holding capacity as mentioned earlier by Roe and Cornforth

(2000). Furthermore, organic manure activates many species of living organisms, which

release phytohormones and may stimulate the plant growth and absorption of nutrients

(Arisha et al., 2003). Such organisms need nitrogen for multiplication. This is the reason

that the use of organic manure with inorganic fertilizer showed a beneficial effect on both

fresh and oven-dry matter.

19

CHAPTER SIX

CONCLUSION AND RECOMMENDATIONS

6.1 Conclusion

This research was carried out in order to evaluate the effect of organic and inorganic

fertilizers on growth and yield of collards. To achieve this objective, those fertilizers were

applied in various plots laid out in randomized complete blocs with three replicates.

According to the results obtained after trial I come with the following conclusions:

1) The results of soil analyses after experiment compared to the initial soil analysis prove

that the mineral and organic fertilizers applied individually or as combination have

improved the soil status and nutrients content in the soil. The exception was always

observed in the control or smoothly in the treatment with N: P: K only.

2) The combination of both farmyard manure and N: P: K revealed a positive impact on

growth of agronomic parameters such as: plant height, number of leaves, stem

diameter and leaf area. This research demonstrated the effects of N: P: K containing

fertilizers and Farmyard-containing fertilizers were different over the time in terms of

plant height, stem diameter and the yield of collards. Collard plants grown in soil

amended with the combination of both Farmyard manure and N:P:K have shown a

vigorous vegetative growth (leaf area, fresh and dry weights), and high yield compared

to the application of either N:P:K or Farmyard manure alone.

3) Based on the results of yield obtained after harvesting, farmyard manure and N: P: K

combined together demonstrated better results on collard yield. The combination of

Farmyard and N: P: K have given 223.0 t/ha yield in average of fresh edible leaves; the

N: P: K alone have resulted 191.7 t/ha yield in average of fresh edible leaves, farmyard

manure has given 158.0 t/ha while the control gave 104.7 t/ha; with respectively 131.0

t/ha; 97.0 t/ha; 73.3t/ha and 51.0t/ha of oven-dry mass of edible leaves. This yield is of

great importance since it may be obtained within short period compared to other

Brassica and can be harvested sequentially.

20

6.2 Recommendations

According to the results obtained in this experimentation, the following recommendations

can be mentioned:

1. The combination of both farmyard manure (10 t/ha) and N: P: K (150 kg/ha)

should recommended for the farmers to increase collards production.

2. The use of organic matter completely decayed also is advisable and should be

promoted to improve chemical, physical and biological condition of the soil and

thus leading to the high yield.

3. Further studies are needed to determine optimal rates of organic fertilizers for

proper growth and production of collards in all corners of the country.

21

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cucumbers (Cucumis sativus L.) using leaf length, width and SPAD value.

Scientia Horticulturae 111(4): 330-334.

ZULKIFLI H. SHAMSUDDIN AND AHMAD HUSNI M.H,1994: combined use of

chemical and organic fertilizers.

25

APPENDICES

The results of soil analysis

Appendix 1:1Soil pH after harvesting after trial

Ttt Bloc1 Bloc2 Bloc3 Average

T1 5.80 5.77 5.73 5.76

T2 6.04 5.64 5.78 5.82

T3 5.79 5.62 6.06 5.82

T4 5.84 5.59 5.96 5.79

Appendix 2: Nitrogen rate after harvesting (%)


T1 0.17 0.22 0.23 0.20

T2 0.33 0.19 0.24 0.25

T3 0.33 0.27 0.31 0.30

T4 0.27 0.18 0.32 0.25

Calculation:

Total N %=( Absorbance read-blank) x2.2

Exemple: (0.158-0.040) x2.2=0.26

26

Appendix 3: Phosphorus rate after harvesting (ppm)


T1 21.2 23.2 22 22.1

T2 35.2 49.6 46.4 43.7

T3 56 53.6 52.8 54.1

T4 30.4 30.8 29.8 30.3

Calculation:

P (ppm)= absorbance-blanc x f.cx f.d

Where : f.c=(facteur de correction) =109

f.d =(facteur de dilution)= 10/3

Appendix 4: Potassium rate after harvesting (meq/100g)


T1 0.39 0.4 0.47 0.42

T2 0.38 0.29 0.36 1.03

T3 1.19 0.76 1.49 1.14

T4 0.97 1.2 0.74 0.97

Calculation :

Kmeq/100gr = (absorbance – blanc) x 165x3

f.c:165

27

Appendix 5: Organic carbon after transplanting


T1 2.63 2.43 2.43 2.6

T2 2.8 2.65 2.7 2.7

T3 3 2.55 3.15 2.9

T4 2.5 2.4 2.4 2.4

Calculation :

% C = (absorbance – blanc) x 80x100x1/1000x f.c

Note that 80x100x1/1000xf.c= 5

That’s to say % C= (absorbance-blanc ) x 5

Example : (0.61-0.14) x 5 = 2.35 and so on

Appendix 6: Organic matter after harvesting


T1 4.53 4.19 4.19 4.30

T2 4.83 4.56 4.65 4.68

T3 5.17 4.39 5.43 4.99

T4 4.31 4.14 4.14 4.19

28

Appendix 7: C/N ration


T1 15.47 11.04 10.56 12.35

T2 8 14.7 8.7 10.46

T3 9.1 9.44 10.16 9.56

T4 9.2 13.3 7.5 10

13

Appendix 8: Effect of treatment on soil chemical composition

Treatment PH-eau N (%) P(ppm) K (meq/100g) C (%) O.M C/N

Initial

Soil

Analysis

After Initial

Soil Analysis

After Initial

Soil Analysis

After Initial

Soil Analysis

After Initial

Soil Analysis

After Initial

Soil

Analysis

After Initial

Soil

Analysis

After

T1

5.83

5.76

0.23

0.20

29.92

22.1

0.78

0.42

2.7

2.6

4.65

4.30

11.7

12.35

T2 5.82 0.25 43.7 1.03 2.9 4.68 10.46

T3 5.82 0.30 54.1 1.14 2.9 4.99 9.56

T4 5.79 0.25 30.3 0.97 2.4 4.19 10

13

Appendix 9: Interpretation norms of pH

pH Highly

acidic

Very

acidic

Fairly

acidic

Slightly

acidic

Neutral Slightly

basic

pH water 3.5-4.2 4.2-5.2 5.2-6.2 6.2-6.9 6.9-7.6 7.6-8.5

pH KCL 3.0-4.0 4.0-5.0 5.0-6.0 6.0-6.8 6.8-7.2 7.2-8.0

Source: Mutwewingabo and Rutunga (1987); quoted by Twizeyimana, 2004

Appendix 10: Interpretation norms of O.M and available P, and total N

Organic matter (% of soil) Appreciation

0.5

0.5-1

1-2

2-5

5-8

8-14

>14

Excessively less humic

Very less humic

Less humic

Moderately humic

Humic

Very humic

Excessively humic

Available P(ppm) Appreciation

<3

3-20

Very low

Low

14

20-50

50-80

>80

Moderate

High

Very high

Nitrogen (%) Appreciation

<0.075

0.075-0.2

0.2-0.5

>0.5

Low

medium

High

Very high

C/N ratio Mineralization

≤ 9

9-12

12-17

17-25

≥ 25

Very quick

Quick

Normal

Slow

Very slow

Source: Mutwewingabo and Rutunga(1987);

The results of agronomic parameters observed

Appendix 11: Number of leaves at 15th day after transplanting


T1 7.25 6.75 6.75 6.916

T2 6.75 7 5.5 6.416

15

T3 7.25 7 6 6.75

T4 8 6.5 6.5 8

Appendix 12: Number of Leaves at 25th days after transplanting


T1 10.75 10.25 9.25 10.08

T2 10 11.75 10.75 10.83

T3 11.5 9.75 10 10.41

T4 12 11.25 12 11.75

Appendix 13: Leaf area at 25th day after transplanting


T1 240.052 225.587 206.862 224.167

T2 390.36 389.263 412.05 397.224

T3 262.547 259.499 313.141 278.39

T4 341.527 355.585 368.67 355.260

16

Appendix 14: Plant height at 15th day after transplanting


T1 10.775 10.375 9.95 10.37

T2 12.375 13.3 11.325 12.3

T3 11.5 11.725 12.7 11.975

T4 15.45 14.35 13.875 14.558

Appendix 15: Plant height at 25th day after transplanting (in cm)


T1 15.75 14.25 12.5 14.16

T2 18.75 19.25 14.375 17.45

T3 15.85 18.25 15.5 16.53

T4 21.25 19.875 21.75 20.95

Appendix 16: plant height at 32th day after transplanting (cm)


T1 18.375 17.375 17.125 17.625

T2 23.55 22.25 18.125 21.30

T3 19.5 22.375 17.75 19.87

T4 24.626 24.25 22.5 23.79

17

Appendix 17: Plant height at the 39th day after transplanting (cm)


T1 20.125 19.25 18 19.125

T2 24.5 24 21.375 23.291

T3 21.25 23 19.625 21.291

T4 25.25 26 24 25

Appendix 18: Plant height at the 46th day after transplanting


T1 21.375 20 18.75 20.04

T2 25.825 25 24.475 25.1

T3 25 26.35 21.75 24.36

T4 26.75 26.25 26.025 26.34

Appendix 19: plant height at the 53rd day after transplanting (cm)


T1 21.875 21.625 21.25 21.58

T2 31 28.25 23.75 27.66

T3 28.625 29.25 25.625 27.8

T4 28.625 29.5 29.25 29.125

18

Appendix 20: Stem diameter at 15th day after transplanting (mm)


T1 7.45 8.635 6.82 7.635

T2 7.912 8.5725 7.675 8.053

T3 7.542 8.7875 7.7375 8.022

T4 8.597 8.7525 7.8325 8.394

Appendix 21: Stem diameter at 25th after transplanting (mm)


T1 15.325 13.8525 13.62 14.26

T2 16.165 18.96 14.56 16.56

T3 15.4 14.282 12.052 13.91

T4 15.91 15.272 14.135 15.10

Appendix 22: Stem diameter at 32th after transplanting(mm)


T1 15.467 14.285 13.635 14.46

T2 17.605 18.555 16.75 17.63

T3 17.752 16.677 15.51 16.64

19

T4 16.765 18.177 18.39 17.77

Appendix 23: Stem diameter at 39th day after transplanting (mm)


T1 17.975 18.32 16.165 17.48

T2 19.465 21.195 20.055 19.57

T3 20.97 19.1725 20.01 20.05

T4 19.835 19.3525 18.72 19.30

Appendix 24 Stem diameter at 46th day after transplanting (mm)


T1 19.5 18.81 18.8175 19.04

T2 21 24.5875 22.245 22.61

T3 21.0625 23.1 23.4375 22.53

T4 21.875 23.1425 21.447 22.15

Appendix 25: Stem diameter at the 53rd day after transplanting (mm)


T1 21.75 19.75 22.25 21.25

T2 22.8625 26.1 24.9375 24.63

T3 22.1876 25.25 24.875 24.10

20

T4 22.605 25.6875 24.66 24.31

Appendix 26: Analysis of Variance of soil pH

Source DF Sum of Squares Mean Square F Ratio

Model 3 0.00616667 0.002056 0.0646

Error 8 0.25460000 0.031825 Prob > F

C. Total 11 0.26076667 0.9771

Appendix 27: Analysis of Variance of Total Nitrogen


Model 3 0.01575833 0.005253 1.5080

Error 8 0.02786667 0.003483 Prob > F

C. Total 11 0.04362500 0.2850

Appendix 28: Analysis of Variance of available phosphorus


Model 3 1808.9700 602.990 39.4025

Error 8 122.4267 15.303 Prob > F

C. Total 11 1931.3967 <.0001

Appendix 29: Analysis of Variance of available potassium


Model 3 1.4292667 0.476422 9.9427

Error 8 0.3833333 0.047917 Prob > F

C. Total 11 1.8126000 0.0045

Appendix 30: Analysis of Variance of organic matter


Model 3 1.2058917 0.401964 4.4663

21


Error 8 0.7200000 0.090000 Prob > F

C. Total 11 1.9258917 0.0402

Appendix 31: Analysis of Variance of plant height at the 15th day


Model 3 26.832917 8.94431 16.2163

Error 8 4.412500 0.55156 Prob > F

C. Total 11 31.245417 0.0009



Model 3 71.436875 23.8123 7.3144

Error 8 26.044167 3.2555 Prob > F

C. Total 11 97.481042 0.0111

Appendix 33: Analysis of Variance of plant height at the 32nd day


Model 3 60.170450 20.0568 5.2779

Error 8 30.401251 3.8002 Prob > F

C. Total 11 90.571701 0.0267



Model 3 59.358073 19.7860 10.1102

Error 8 15.656250 1.9570 Prob > F

C. Total 11 75.014323 0.0043



22


Model 3 67.471875 22.4906 11.3652

Error 8 15.831250 1.9789 Prob > F

C. Total 11 83.303125 0.0030

Appendix 36: Analysis of Variance of plant height at the 53rd day


Model 3 101.30599 33.7687 7.7718

Error 8 34.76042 4.3451 Prob > F

C. Total 11 136.06641 0.0093

Appendix 37: Analysis of Variance of number of leaves at the 15th day


Model 3 0.5989583 0.199653 0.4167

Error 8 3.8333333 0.479167 Prob > F

C. Total 11 4.4322917 0.7459

Appendix 38: Analysis of Variance of number of leaves at the 25th day


Model 3 4.6822917 1.56076 2.5613

Error 8 4.8750000 0.60938 Prob > F

C. Total 11 9.5572917 0.1279

Appendix 39: Analysis of Variance of stem diameter at the 15th day


Model 3 0.8671692 0.289056 0.6582

Error 8 3.5134388 0.439180 Prob > F

C. Total 11 4.3806081 0.6003


23


Model 3 12.504357 4.16812 1.7501

Error 8 19.053251 2.38166 Prob > F

C. Total 11 31.557608 0.2341

Appendix 41: Analysis of Variance of stem diameter at the 32nd day


Model 3 21.086386 7.02880 7.5676

Error 8 7.430405 0.92880 Prob > F

C. Total 11 28.516791 0.0101



Model 3 14.186110 4.72870 5.8470

Error 8 6.469950 0.80874 Prob > F

C. Total 11 20.656060 0.0205



Model 3 26.222058 8.74069 5.9226

Error 8 11.806616 1.47583 Prob > F

C. Total 11 38.028674 0.0198

Appendix 44: Analysis of Variance of stem diameter at the 53rd day


Model 3 22.071141 7.35705 3.0359

Error 8 19.386688 2.42334 Prob > F

C. Total 11 41.457829 0.0929

Appendix 45: Analysis of Variance of leaf area

24


Model 3 32693.536 10897.8 6.5155

Error 8 13380.866 1672.6 Prob > F

C. Total 11 46074.402 0.0153

Appendix 46: Analysis of Variance of fresh weight at the 25th day


Model 3 190204.68 63401.6 2.3896

Error 8 212256.15 26532.0 Prob > F

C. Total 11 402460.83 0.1444

Appendix 47: Analysis of Variance of fresh weight at the 39th day


Model 3 107854.05 35951.4 13.5254

Error 8 21264.53 2658.1 Prob > F

C. Total 11 129118.59 0.0017

Appendix 48: Analysis of Variance of fresh weight at the 53rd day


Model 3 230383.07 76794.4 10.0779

Error 8 60960.82 7620.1 Prob > F

C. Total 11 291343.89 0.0043

Appendix 49: Analysis of Variance of total fresh weight in t/ha


Model 3 10579.053 3526.35 20.0144

Error 8 1409.527 176.19 Prob > F

C. Total 11 11988.580 0.0004

Appendix 50: Analysis of Variance of total fresh weight in grams/ha

25


Model 3 8972307 2990769 19.0657

Error 8 1254931 156866 Prob > F

C. Total 11 10227238 0.0005

Appendix 51: Analysis of Variance of Total oven-dry mass in grams/ha


Model 3 882454.0 294151 16.2240

Error 8 145045.4 18131 Prob > F

C. Total 11 1027499.4 0.0009

Appendix 52: Analysis of Variance of Total oven-dry mass in tones/ha


Model 3 44.622451 14.8742 16.2240

Error 8 7.334412 0.9168 Prob > F

C. Total 11 51.956863 0.0009

Appendix 53: Picture in the field from the beginning up to the end of the experiment

26

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