Reproductive Vigor in Bemisia argentifolii (Homoptera: Aleyrodidae) Associated With Bifenthrin Resistance

A bifenthrin-selected whitefly population, Bemisia argentifolii Bellows & Perring, exhibited reproductive vigor in several backcrosses compared to both the bifenthrin-resistant and bifenthrin-susceptible parent populations. Net reproductive rates (R₀) ranged from 5.7 to 32.9 with the highest rates occurring in populations resulting from resistant × susceptible F₁ females backcrossed to males from the same resistant parent population. The genetic mechanism for increased vigor in the backcrosses of bifenthrin-resistant whiteflies is not known.