ABSTRACT
The consumptive use of water assures all year round production of groundnut prone to the vagaries of weather and climate. This brought about the need to supply moisture that is naturally available through rainfall. The successful design of any irrigation system requires the knowledge of the consumptive use of water by the crop under consideration. This need led to the investigation of the water use rate of groundnut in a typical area found in Awha-Imezi of Ezeagu in Enugu State of Nigeria. Climate data required for computing or estimating consumptive use of water for groundnut using the Blaney-Criddle method were obtained from Awha-Imezi, the same area as the location of this case study. The determination was for the period of the study, April to August, 2013. Field measurements were carried out to determine the consumptive use of groundnut with the aid of a portable non-weighing lysimeter. The estimated values of consumptive use as determined by the Blaney-Criddle method were lower than those determined experimentally. It was then recommended that a more elaborate study that would spread throughout the life span of the plant be conducted to confirm the results that were obtained so far. This would be required for irrigating the crop throughout its growing season.
TABLE OF CONTENT
Title page i
Approval page ii
Dedication iii
Acknowledgment iv
Abstract v
List of tables vi
List of figures vii
CHAPTER ONE: INTRODUCTION
1.1 Economic Importance of the study 1
1.2 Objectives of the study 3
1.3 Scope of the study 4
CHAPTER TWO: LITERATURE REVIEW
2.1 Description of the Groundnut Plant and Species 6
2.2 Groundnut Cultivation 9
2.2.1 Cultivars 9
2.2.2 Environment Response 10
2.2.3 Cultural Requirements 10
2.2.4 Irrigation 13
2.2.5 Nutrient Requirements 13
2.2.6 Growth Period and Harvesting 14
2.2.7 Yield 14
2.2.8 Seed production 14
2.2.9 Use and Nutritional Composition 14
2.2.10 Diseases/pest Control 15
2.3 Evapotranspiration (ET) 15
2.3.1 Main Concept 16
2.3.2 Factor Affecting ET 18
2.3.3 Measurement of ET 18
2.3.3I Soil Moisture Depletion studies 19
2.3.3 II Lysimeter Experiments 20
2.3.3.III Field experiment Plots 21
2.3.3.IV Water balance Method 22
2.4 Estimating ET from Evaporation Data Pan Method 27
2.5 Estimating Et from Climatological data 29
2.5.1 Blaney-Criddle method 30
2.5.2 FAO Penman-Monteith Method 33
2.6 Estimating Crop Coefficient 35
2.7 Measurement of Soil Moisture 40
2.8 Previous studies on Consumptive Use of Crops 42
CHAPTER THREE
3.0 Experimental Procedure 45
3.1 Description of the Experiment Plot 45
3.1.1 Portable Non-weighing Lysimeter and field Layout 45
3.2 Characterization of soil Physical properties 48
3.2.1 Textural Class 48
3.2.2 Specific Gravity 49
3.2.3 Bulk Density 50
3.2.4 Porosity 50
3.2.5 Field Capacity 51
3.2.6 Permanent Wilting Point 51
3.2.7 Available Moisture 52
3.3 Measurement of Soil Moisture Content 52
3.3.1 By Gravimetric Method 53
3.3.2 Resistance Block 53
CHAPTER FOUR: DATA PRESENTATION
AND ANALYSIS 55- 72
CHAPTER FIVE RESULTS AND DISCUSSION 72
CHAPTER SIX: CONCLUSION AND RECOMMENDATION 75
APPENDIX 77- 84
REFERENCES 85
LIST OF TABLES
Table 1: The major producers of groundnut in the shell and the major producing countries.
Table 2. Range of inorganic constituents occurring in peanut kernels.
Table 3: Values of crop factor to compute consumptive use from pan evaporation data.
Table 4: Hydrometer reading
Table 5: Soil analysis data
Table 6: Soil property determination and calibration data
Table 7: Evapotranspiration data for the month
Table 8: Evapotranspiration values determined by lysimeter method.
Table 9: Groundnut daily crop consumptive use for the month of April 2013.
Table 10: Groundnut daily crop consumptive use for the month of May 2013.
Table 11: Groundnut daily crop consumptive use for the month of June 2013.
LIST OF FIGURES
Figure 1: The pods and kernels of the Dixie Spanish and North Carolina varieties of peanuts.
Figure 2: Simple drainage lysimeter (non-weighing)
Figure 3: Small weighing lysimeter.
Figure 4: Generalized crop coefficient curve during the growing season and stage definitions.
Figure 5: Crop coefficient definition showing the basal keb, ke, and time average (keb + ke values).
Figure 6: Portable non-weighing lysimeter
Figure 7: Experimental field layout.
Figure 8: USDA textural class.
Figure 9: Calibration curve of resistance block for a sand loam soil.
Figure 10: Groundnut evapotranspiration curve determined by lysimeter method.
