Evaluation of Planting Dates on Growth and Yield of Three Cowpea [Vigna unguiculata (L) Walp.] Genotypes in Northern Ghana

Abstract

Background: Time of planting has remarkable influence on both yield and yield components of crops and therefore identification of the appropriate planting time is essential for crop improvement. Aims: To assess the effect of planting dates on growth and yield of three cowpea genotypes. Study Design: The study was designed as 3×4 factorial experiments in a randomized complete block design. Place and Duration of Study: The study was carried in the field over a three-month period at the Savanna Agricultural Research Institute, Tamale-Northern Ghana. Methodology: The study was designed as 3×4 factorial experiments in split-plot in randomized complete block design. The genotypes were 3 genotypes with 4 planting dates. Treatment combinations were replicated three times. Results: Analysis of variance indicated significant effects on percentage germination, plant height at flowering, plant height at maturity and at harvest, pods per plant, pod yield and seeds per pod. Padi- tuya performed better than the other two genotypes in terms of performance for grain yield for all the planting dates. However, there were no significant difference between the first planting and second planting date. Conclusion: Padi-tuya was the most superior variety for grain yield. To achieve higher yields, cowpea should be planted between the middle of July and Early August. Early planting resulted in maturity coinciding with wet period resulting in reduction in quality of seeds. Late planting especially in late August resulted in poor yields.