Effect of different phosphorus levels on four cowpea (Vigna unguiculata Walp L.) varieties for grain and fodder yield in Upper East Region of Ghana

Abstract

A field experiment was conducted to examine the effect of cowpea varieties and different phosphorus levels on grain and fodder yield. Four cowpea varieties i.e. Asetenapa, Asomdwe, Hewale and Videza with four different phosphorus levels of single superphosphate (SSP) were used in the experiment. The experimental design was 4 × 4 factorial experiment laid in randomized complete block with four replicates. The results showed that cowpea varieties and phosphorus levels significantly influenced number of nodules per plant, pod length, number of pods per plant, fodder yield and grain yield. Phosphorus levels had no significant effect on stem girth, plant height and 100 seed weight. Asomdwe recorded the highest grain yield of 1229kgha^-1 while Videza and Asetenapa produced the highest fodder yield of 957kgha^-1. Interactive effect between Videza and 30kgha^-1 of SSP produced the highest fodder yield while Asomdwe and 60kgha^-1 of SSP was the treatment combination that produced the highest grain yield. Cowpea varieties and different phosphorus levels had effect on grain and fodder yield. Asomdwe would be recommended for commercial grain production because of the high grain yielding potential as observed in the study Asetenapa and Videza for fodder production to feed livestock.