Measuring susceptibility in maize varieties in free and no choice tests against Sitophilus oryzae (L.) and Rhyzopertha dominica (F.)

Among six maize varieties evaluated against Sitophilus oryzae and Rhyzopertha dominica, Madhuri (sweet corn) and Shaktiman-1 (Quality protein maize) remained most and least susceptible, respectively, when released in equal numbers in interspecific competition in no choice test. S. oryzae was found to be dominating species over R. dominica in competition in all six maize varieties tested. S. oryzae showed significant correlation with grain weight loss and R. dominica with flour produced. In free choice test, Shaktiman-1 attracted nearly 60% S. oryzae but its population build-up and % weight loss was not significantly different from Madhuri which attracted only 15% of the released insects. In no choice test, variety Basi local was intermediate in susceptibility but was found least susceptible to R. dominica in free choice test.