Studies on the legume pod-borer, Maruca testulalis (Geyer)—VI. Cowpea resistance to oviposition and larval feeding

Abstract

Three cowpea cultivars, TVu 946, Ife Brown and Vita 1 were examined for resistance to the legume pod-borer, Maruca testulalis (Geyer). TVu 946 was found to be the most resistant in both the flowering and pre-flowering stages, followed by Ife Brown and Vita 1, respectively. Field and screen-house experiments show that Maruca larvae caused significantly less damage on TVu 946 than on Ife Brown and Vita 1. In addition, larval survival and development on TVu 946 was the most negatively affected. Screenhouse experiments in a choice situation clearly show non-preference of TVu 946 for oviposition by adult Maruca females, and biochemical studies show evidence of antibiosis due to nutritional and antibiotic factor(s).