Performance of vegetable cowpea (Vigna unguiculata L. walp) as influenced by P fertilizer in S.E. Nigeria

Abstract

Four cultivars of cowpea (IT 86F-2089-5, IT 81D-1228-14, IT 92KD-267-2 and IT 92KD-266-2-1) were subjected to four levels of phosphorus fertilizer in Calabar, southeastern Nigeria during the 1995 cropping season. Morphological differences were minimal between the erect and prostrate, bushy types. Significant cultivar differences for green pod yields were obtained, with IT 86F-2089-5 giving the highest and IT 92KD-266-2-1 the lowest yields. For all cultivars except IT 81D-1228-14, the phosphorus fertilizer effect increased with increasing rate of application. The green pod yields of IT 86F-2089-5 and IT 81D-1228-14 were superior to those of other cultivars, whereas the grain yield was highest in the latter cultivar. In addition, IT 81D-1228-14 gave high yields even without P fertilizer, hence it could be a useful variety for low-input farmers in the area. © 2001 Akadémiai Kiadó, Budapest.