Genetic analysis of pod quality characteristics in vegetable cowpea (Vigna unguiculata L. Walp.)

A preliminary study of consumer preferences for pod characteristics in Vegetable cowpea showed a general preference for greener, longer, fleshier pods that are less seedy. Methods of quantitatively assessing these traits were developed and used in understanding the inheritance of pod quality traits. Combining ability analysis, involving a 6 x 6 diallel mating design, showed that GCA effects were predominant for all pod characteristics. The additive effects were especially high for pad seediness. The dominance effect was, nevertheless, significant for all the characters. The dominance effects were unidirectional in the case of pod wall thickness and were in the direction of the thin walled parent. Dominance was ambidirectional for the other characteristics investigated. The study showed that it is relatively easy to improve these characters by carefully selecting the parents in hybridisation programmes. (C) 1997 Elsevier Science B.V.