Influence of Resource Quality on the Reproductive Fitness of Flower Thrips (Thysanoptera: Thripidae)

Abstract

Reproductive fitness of the flower thrips, Frankliniella occidentalis (Pergande), was much lower on leaves of a cotton variety resistant to spider mites, Tetranychus urticae Koch, than on leaves of a spider mite-susceptible variety. The addition of mite eggs or pollen to cotton leaves significantly improved several fitness traits of flower thrips. Pollen was nutritionally better than mite eggs. The addition of pollen lowered the time from egg to adult, increased fecundity, and improved longevity over that which occurred on leaf tissue alone. The effect of pollen was more pronounced on resistant than on susceptible leaves. Pollen raised the intrinsic rate of increase (r) by 0.063 on susceptible leaves and by 0.202 on resistant leaves. When pollen is available, flower thrips can completely overcome the negative effects of resistant leaves.