When host choice is a problem for a generalist herbivore:: experiments with the whitefly, Bemisia tabaci

1. Experiments with adult females of the whitefly, Bemisia tabaci, demonstrated that when mixtures of host plants were present, performance was reduced relative to that on the best of the host plants when presented alone. 2. Behavioural observations indicated that in the presence of a variety of plants, individuals moved more, switched between plants more frequently, and stayed feeding in one place for shorter periods of time, compared with the situation when single plant species were available. 3. The data are interpreted as a constraint on attentiveness in the presence of complex, mixed-sensory stimuli.