Evaluation of Yield and Yield Components of Some Cowpea (<i>Vigna unguiculata</i> (L.) Walp) Genotypes in Forest and Transitional Zones of Ghana

Abstract

Cowpea adapts very well to environmental conditions that normally affect production of crops such as drought, temperature changes and other environmental stresses. However, apart from these attributes, the growth and development of some cowpea genotypes especially during flowering stage and yield of some cowpea are affected by drought and high temperatures. Two field trials were conducted at two different locations (Mampong and Fumesua) in the 2015 and 2016 growing seasons to evaluate yield stability of eight cowpea varieties (Asontem, Tona, Nhyira, Videza, Asomdwe, Asetenapa, Soronko and Tona) released over two decades ago by CSIR-CRI in the forest and transitional zones of Ghana. The experimental design used was a Randomized Complete Block Design with three replications. The results revealed that Asontem, Tona and Nhyira had high yields in both locations and across seasons. Asontem showed superiority amongst the genotypes across the seasons and locations with Soronko and Asetenapa having the lowest yields. The growth and development of the cowpea genotypes especially during flowering stage and yield were affected by drought and high temperatures, hence Soronko and Asetena had low yields compared to Asontem and other genotypes. It is recommended that, for farmers to get more profit due to unpredictable climatic conditions prevailing in Ghana, it will be profitable to grow early maturing cowpeas such as Asontem that can be stable across different environments in order to get stable yields with good returns.