Mechanism of resistance in cowpea (Vigna unguiculata (L.) Walp.) genotype, TVx 3236, to the Bean Flower Thrips, Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae) 1. Ovipositional nonpreference

Abstract

Oviposition of the bean flower thrips, (BFT) (Megalurothrips sjostedti) on the thrips‐resistant cowpea genotype TVx 3236 was compared with that of four other genotypes on field and screenhouse experiments. TVx 3236 and its resistant parent (TVu 1509) were significantly nonpreferred for oviposition by BFT in field experiments. In choice/no choice experiments in the screenhouse, TVx 3236 was also nonsignificantly preferred for oviposition in comparison with the susceptible genotype VITA 7. The physical basis of ovipositional nonpreference appeared to be associated with reduced air spaces in the calyx tissue of TVx 3236.

Keywords:

• antibiosis
• nonpreference
• Bean Flower Thrips
• cowpea
• oviposition
• calyx structure

Notes

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