Biological Control of Bemisia tabaci (Homoptera: Aleyrodidae) in a Greenhouse Using Chrysoperla rufilabris (Neuroptera: Chrysopidae)

First and second instar Chrysoperla rufilabris(Burmeister) were evaluated as control agents for sweet potato whitefly, Bemisia tabaci (Gennadius), on Hibiscus rosa-sinensis L. in a greenhouse. Two inundative releases of 25 or 50 C. rufilabris larvae per plant at an interval of 2 weeks maintained all plants in a marketable condition. Two releases of 100 C. rufilabris larvae toward the center of 12 plants also maintained marketability. While most plants with 5 C. rufilabris larvae each remained marketable, the majority of the untreated plants were unmarketable at the end of the experiment. Qualitative evaluation of plant marketability was based on the presence of sooty mold and physical effects of B. tabaci on the plants 2 weeks after the last release of C. rufilabris larvae. (C) 1992 Academic Press, Inc.