ABSTRACT
Three field experiments were conducted at the National Root Crops Research Institute (NRCRI), Umudike experimental field (located on longitude 07˚ 33̍ E and latitude 05˚ 29̍ N and at an elevation of 122 m above sea level in the rainforest agro-ecological zone of Nigeria) in 2014 and 2015 cropping seasons. The experiments were laid in a randomized complete block design (RCBD) with three replications. Each plot size was 6m x 4m (24m2). Land equivalent ratio (LER) and Gross monetary returns (GMR) and net returns (NR) were used to assess the productivity of the intercropping systems. The first experiment was to determine the effect of eggplant population on growth and yield of component crops in sweetpotato/eggplant intercropping system. It consisted of four eggplant populations (10,000; 20,000; 30,000 and 40,000 plants/ha) and two sweetpotato varieties of Umuspo 1 and TIS 87/0087 at 33,333 plants/ha each. The second experiment was on the effect of time of introduction of eggplant in sweetpotato/eggplant intercrop. There were three different times of introduction such as simultaneous planting of eggplant and sweetpotato; eggplant 2 weeks before planting (WBP) and 2 weeks after planting (WAP) sweetpotato varieties; eggplant 4 WBP and 4 WAP sweetpotato varieties. The third experiment evaluated the effect of organic and inorganic fertilizers application on growth and yield of component crops of sweetpotato/eggplant intercrop. The treatments were made up of 3 rates of NPK 15:15:15 fertilizer (0, 300 and 600 kg/ha) and 2 levels (5 and 10t/ha) of poultry manure (PM). In the first experiment, intercropping reduced the growth and yield parameters of eggplant and sweetpotato. Optimum yield was achieved at mixture of 10,000 eggplant + 33,333 sweetpotato (plants/ha). Land equivalent ratio (LER) in the two years of study was mostly above 1.00. Best performance (1.79) was obtained from 10,000 eggplant + 33,333 sweetpotato (plants/ha) in 2014 and (1.60) from 20,000 eggplant + 33,333 sweetpotato (plants/ha) in 2015. The best gross monetary returns (GMR) and net returns (NR) for both years were from a population of 10,000 eggplant + 33,333 sweetpotato (plants/ha). In the second experiment, the result showed that intercropping decreased growth and yield parameters of eggplant and sweetpotato. Simultaneous planting of eggplant and sweetpotato was the best time of introduction. LER for both years were above unity for all times of introduction but the best productivity in both years was obtained with simultaneous planting of eggplant and sweetpotato. The highest GMR and NR for both years also came from simultaneous planting of eggplant and sweetpotato. The result of the third experiment indicated also that intercropping reduced the growth and yield parameters of eggplant and sweetpotato. LER in all the applications were above unity, with the application of 300kg/ha of NPK 15:15:15 fertilizer + 5t/ha PM giving the best result. The same trend was observed with the GMR and NR. In both years of study, intercropping was more productive than sole cropping and gave greater revenue. The greatest net return in mixture was obtained when NPK fertilizer was applied at 300kg/ha and poultry manure at 5t/ha on average. From the results obtained intercropping sweetpotato and eggplant at mixture of 33,333 sweetpotato + 10,000 eggplant plants/ha; simultaneous planting of sweetpotato and eggplant; and application of 300kg/ha of NPK 15:15:15 fertilizer + 5t/ha PM were recommended for maximum crop productivity and income generation.
TABLE OF CONTENTS
Title Page
i
Declaration
ii
Certification iii
Dedication
iv
Acknowledgements v
Table of
Contents
vi
List of
Tables ix
Abstract xii
CHAPTER 1: INTRODUCTION 1
CHAPTER 2:
LITERATURE REVIEW
5
2.1 Intercropping 5
2.2 Types
of Intercropping 6
2.2.1 Row intercropping 6
2.2.2 Mixed intercropping 7
2.2.3 Strip intercropping 7
2.2.4 Relay intercropping 7
2.2.5 Patch intercropping 7
2.2.6 Intercropping practice 7
2.3 Advantages of Intercropping 7
2.3.1 Increase
in yield 8
2.3.2 Efficient
use of environmental resources 8
2.3.3 Reduction
of pests, diseases and weeds 9
2.3.4 Stability
and uniform yield 10
2.3.5 Improvement
in soil fertility and nitrogen 10
2.3.6 Increase
income per unit area 11
2.4 Disadvantages
of Intercropping 11
2.5 Resources used in intercropping 12
2.5.1 Sunlight in intercropping systems 12
2.5.2 Soil water or moisture in
intercropping systems 13
2.5.3 Soil nutrient uptake in intercropping
system 13
2.5.4 Weed control in intercropping systems 13
2.5.5 Pest and diseases in intercropping
systems 14
2.6 Spacing in intercropping systems 15
2.6 .1 Plant populations/ Density in
Intercropping System 15
2.6.2 Relative
time of Introduction of Component Crops in Intercropping
Systems 16
2.6.3 Fertilizer Requirement in
Intercropping 16
2.7 Methods
of Assessing Crop Performance and Yield in Intercropping Systems 17
2.7.1 Land
equivalent ratio (LER) 18
2.7.2 Land
equivalent coefficient (LEC) 19
2.7.3 Area
x time equivalent ratio (ATER). 19
2.7.4 Competitive
ratio (CR) 20
2.7.5 Relative
yield total (RYT) 21
2.7.6 Economic
evaluation of production in intercropping systems 21
CHAPTER 3: MATERIALS AND METHODS 22
3.0 Study Area and Location 22
3.1 Experiment 1: Effect
of Eggplant Population on Growth and Yield of
Component Crops in
Sweetpotato/Eggplant Intercropping System 22
3.1.1 Land preparation 22
3.1.2 Planting materials 23
3.1.3 Experimental design and field lay out 23
3.1.4 Experimental treatments 23
3.1.5 Planting and cultural operations 25
3.1.6 Data collection 25
3.1.7 Data analysis 27
3.1.7 (1) Land Equivalent Ration
(LER) 28
3.1.7 (2) Gross Monetary Return
(GMR) 28
3.1.7 (3) Net Returns 28
3.2 Experiment
2: Effect of relative time of introduction of
eggplants in sweetpotato/eggplant intercropping system 28
3.2.1 Land preparation 28
3.2.2 Planting material 29
3.2.3 Experimental design
and field lay out 29
3.2.4 Experiment treatment 29
3.2.5 Planting and cultural
operations 30
3.2.6 Data collection 31
3.2.7 Data analysis 33
3.2.7 (a) Land Equivalent Ratio
(LER) 33
3.2.7 (b) Gross Monetary Ration
(GMR) 34
3.3.0 Experiment 3: Effect
of organic and inorganic fertilizers on growth
and yield of component
crops of Sweetpotato/Eggplant intercrop 34
3.3.1 Land preparation 34
3.3.2 Planting materials 34
3.3.3 Experimental design and field lay out 35
3.3.4 Experimental treatment (organic and inorganic fertilizers) 35
3.3.5 Treatment
combinations 35
3.3.6 Planting and cultural operations 37
3.3.7 Data collection 37
3.3.8 Data analysis 39
CHAPTER 4: RESULTS AND DISCUSSION
4.1 Results 40
4.1.1 Soil Physico-chemical Properties and
Meteorological Data of
Experimental Sites 40
4.2 Experiment 1: Effect of Eggplant Population on Growth and
Yield of
Components Crops
in Sweetpotato/Eggplant Intercropping System
43
4.2.1 Eggplant growth parameters 43
4.2.2
Eggplant yield and yield components 44
4.2.3 Sweetpotato growth parameters 44
4.2.4 Sweetpotato yield and yield components 54
4.2.5 Weed dry matter 54
4.2.6 Productivity of the intercropping systems 55
4.2.7
Discussion experiment 1 65
4.3 Experiment 2: Effect
of Time of Introduction of Eggplant in
Sweetpotato/Eggplant
Intercropping System 67
4.3.1 Eggplant growth parameters 67
4.3.2 Eggplant yield and yield components 68
4.3.3: Sweetpotato growth
attributes 68
4.3.4: Sweetpotato yield and yield components 69
4.3.5 Weed dry matter 69
4.3.6 Productivity of the intercropping systems 70
4.3.7 Discussion experiment 2 82
4.4 Experiment 3: Effect of Organic and
Inorganic Fertilizers on
Growth
and Yield of Component Crops of Sweetpotato/Eggplant Intercrop 84
4.4.1 Growth attributes of
eggplant 84
4.4.2 Eggplant yield and yield components
84
4.4.3: Sweetpotato growth attributes 85
4.4.4: Sweetpotato yield and yield components
89
4.4.5 Weed dry matter 92
4.4.6 Productivity of the intercropping systems 92
4.4.7 Discussion experiment 3 100
5.0 CHAPTER
5: CONCLUSION AND RECOMMENDATIONS
5.1 Conclusion 102
5.2 Recommendations 102
References 104
Appendices
116
LIST TABLES
4.1: Physical
and chemical properties of the experimental site in 2014 and 2015 cropping
seasons 41
4.2: Monthly
total rainfall (mm), rainy days, sunshine (hr), maximum and minimum temperature
in 2014 and 2015 42
4.3: Effect
of cropping system and eggplant population on growth and growth parameters
of eggplant at 8 WAP and 10 WAP in 2014 cropping season 45
4.4: Effect
of cropping system and eggplant population on growth and growth parameters of
eggplant at 8 WAP and 10 WAP in 2015 cropping season 46
4.5: Effect
of cropping system and eggplant population on yield and yield components of
eggplant in 2014 and 2015
47
4.6: Effect
of interaction cropping system and sweetpotato varieties on fruit girth of eggplant in 2014 and 2015 48
4.7: Effect
of cropping system and eggplant population on growth and growth parameters
of sweetpotato varieties in 2014 cropping season 49
4.8: Effect
of cropping system and eggplant population on growth and growth parameters
of sweetpotato in 2015 cropping season 50
4.9: Interaction
effects of cropping system and sweetpotato varieties on growth parameters of sweetpotato in
2014 51
4.10: Interaction
effect for cropping system and sweetpotato varieties on growth and growth parameters of
sweetpotato in 2015 52
4.11: Interaction
effect of sweetpotato varieties and eggplant population on vine length of
sweetpotato in 2014 and 2015 53
4.12: Effect
of cropping system and eggplant population on yield and yield components of
sweetpotato varieties in 2014 57
4.13: Effect
of cropping system and eggplant population on yield and yield components of
sweetpotato in 2015 cropping season 58
4.14: Interaction
effects for cropping system and sweetpotato varieties on yield and yield components of sweetpotato
varieties in 2014 and 2015 cropping seasons 59
4.15: Interaction
effect of sweetpotato varieties and eggplant population on some yield components of sweetpotato
in 2015 60
4.16: Effect
of cropping system and eggplant population on weed dry weight at 8 WAP and 10 WAP in 2014 and 2015
cropping seasons 61
4.17: Effect
of component population of eggplant/sweetpotato intercropping on land equivalent ratio (LER) and gross
monetary returns (GMR) in 2014 cropping season 62
4.18: Effect
of component population of eggplant/sweetpotato intercropping on land equivalent ratio (LER) and gross monetary
returns (GMR) in 2015 cropping
season 63
4.19: Gross
monetary returns (₦/ha), total revenue variable cost and net returns (₦/ha) as effected by eggplant population on
sweetpotato/eggplant on 2014 and 2015 cropping
seasons 64
4.20: Effect
of cropping system and time of introduction of eggplant on growth and growth parameters of eggplant
in 2014 71
4:21: Effect
of cropping system and time of introduction of eggplants on growth parameters of eggplants in
2015 72
4.22: Effect
of cropping system and time of introduction of eggplant on yield and yield components of eggplant
in 2014 and 2015 73
4.23: Effect
of cropping system and time of introduction of eggplant on growth parameters
of sweetpotato in 2014 74
4.24: Effect
of cropping system and time of introduction of eggplant on growth parameters
of sweetpotato in 2015 75
4.25: Effect
of cropping system and time of introduction of eggplant on yield and yield components of
sweetpotato in 2014 76
4.26: Effect
of cropping system and time of introduction on yield and yield components of
sweetpotato in 2015 77
4.27: Effect
of cropping system and time of introduction on weed dry matter of sweetpotato in
2014 and 2015 78
4.28: Effect
of time of introduction of eggplant in sweetpotato/eggplant intercropping
system on land equivalent ratio (LER) and gross monetary returns (GMR) in
2014 79
4.29: Effect
of time of introduction of eggplant in sweetpotato/eggplant intercropping
system on land equivalent ratio (LER) and gross monetary returns (GMR) in
2015 80
4.30: Gross
monetary returns (₦/ha), total revenue variable cost and net returns (₦/ha) as effected by time of introduction of
eggplant in sweetpotato/ eggplant intercropping
system in 2014 and 2015 cropping seasons 81
4.31: Effect
of cropping system, NPK 15:15:15 fertilizer and poultry manure on growth parameters
of eggplant in 2014 86
4.32: Effect
of cropping system, NPK 15:15:15 fertilizer and poultry manure on growth parameters
of eggplant in 2015 87
4.33: Effect
of cropping system, NPK fertilizer and poultry manure on yield and yield components of eggplant
in 2014 and 2015 88
4.34: Effect
of cropping system, NPK 15:15:15 fertilizer and poultry manure on growth and growth
parameters sweetpotato in 2014 90
4.35: Effect
of cropping system, NPK 15:15:15 fertilizer and poultry manure on growth and growth
parameters of sweetpotato in 2015 91
4.36: Effect
of cropping system, NPK 15:15:15 fertilizer and poultry manure on yield and yield
components of sweetpotato in 2014 93
4.37: Effect
of cropping system, NPK 15:15:15 fertilizer and poultry manure on yield
and yield components of sweetpotato in 2015 94
4.38: Effect
of cropping system, NPK 15:15:15 fertilizer and poultry manure on weed dry matter
(WDM) of sweetpotato and eggplant in 2014 and 2015 95
4.39: Effect
of poultry manure and NPK 15:15:15 fertilizer on eggplant/sweetpotato intercropping on land equivalent
ratio (LER) and gross monetary returns (GMR)
in 2014 97
4.40: Effect
of poultry manure and NPK 15:15:15 fertilizer on eggplant/sweetpotato intercropping on land equivalent
ratio (LER) and gross monetary returns (GMR)
in 2015 98
4.41: Gross
monetary returns (₦/ha), total revenue variable cost and net returns (₦/ha) as effected
by poultry manure and NPK 15:115:15 fertilizer sweetpotato eggplant intercropping in 2014 and
2015 cropping seasons 99
Login To Comment