Preliminary results on the preferences of Callosobruchus maculatus on Apulian germplasm of Cicer arietinum

Abstract

The susceptibility of six genotypes of Cicer arietinum L. (Fabaceae) to Callosobruchus maculatus (Fabr.) (Coleoptera: Bruchidae) was evaluated through comparative laboratory bioassays. The egg-laying amount, pattern of adult emergence, median development time and pre-adult mortality were assessed under free-choice and no-choice bioassays on three local genotypes (Altamura, Grumo Appula White and Grumo Appula Black) and three commercial varieties (Barraco, Sultano and standard of large-scale retail trade as control). Trials were performed on a completely randomized experimental design under artificial conditions with the release of males and females (ratio 1:3), at the most 24-h old. Among the assayed genotypes, the local one provided with a black coat (Grumo Appula Black) was significantly (P<0.05) the least susceptible to the cowpea beetle owing to the least number of laid eggs (2.0±1.8 under free-choice and 2.2±1.3 under no-choice bioassays), the delayed median developmental time (30.3±0.6 and 32.3±0.6, respectively), the lower adult emergence (45.6 and 46.2, respectively) and susceptibility index (7.7±2.04 and 7.8±0.51, respectively).