Comparative Demographic Traits of the Whitefly (Bemisia tabaci) B Biotype against different Host Plants

The sucking pests, especially whitefly, have damaged various fields and fruit crops across the globe. The study of life-history is of prime importance to monitor the dynamics for preference of a species to its host. This study tested the prevalence and preference of a whitefly species, Bemisia tabaci (Gennadius) B biotype (Hemiptera: Aleyrodidae) on tomato, cotton, pepper, and okra as hosts using age-stage two-sex life table. Results revealed the highest pre-adult developmental duration, survival rate, and fecundity on tomato while the lowest values on okra. Population parameters such as the net reproductive rate (R0), intrinsic rate of increase (r), and finite rate of increase (λ) were demonstrated longer on cotton and tomato compared to much lower R0, r, and λ on pepper and okra. Okra responded significantly differently in the case of the mean generation time, T among all tested genotypes. These findings suggest the possibility of summer vegetables as more favorable hosts for B. tabaci. © 2021 Friends Science Publishers

Antibiosis and antixenosis resistance to oviposition by Bemisia tabaci (Gennadius) B biotype (Hemiptera: Aleyrodidae) in soybean genotypes

ABSTRACT: This study was aimed at assessing some biological parameters of Bemisia tabaci B biotype at immature stages to examine antibiosis in six soybean genotypes, besides antixenosis resistance to oviposition in choice and non-choice tests, under greenhouse and laboratory conditions. Between April 2016 and August 2016, bioassays were carried out at the Laboratory of Applied Entomology at College of Agricultural Sciences at Federal University of Grande Dourados (UFGD) Dourados (MS), Brazil. The following variables were evaluated: egg incubation period, nymphal and egg-to-adult duration, egg and nymph viability, and egg-to-adult survival on the soybean genotypes 68i70 RSF IPRO, M6210 IPRO, MS 947 IPRO, BMX Potência RR, M6410 IPRO, and ANTA 82 RR. Antixenosis resistance to oviposition by the silverleaf whitefly was found for MS 947 IPRO, while oviposition was highest for ANTA 82 RR, M6210 IPRO, and M6410 IPRO. The genotype MS 947 IPRO adversely affected egg and nymph viability, and egg-to-adult survival rates was the lowest among genotypes (59.75%), suggesting antibiosis resistance to this pest.