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The toxicity of fourteen different pesticides used in 'Tahiti' lime, Citrus aurantifolia (Christman) Swingle, to the spider, Hibana velox (Becker) was tested under laboratory conditions. Among the nine pesticides tested using a coated glass vial method, the five broad-spectrum insecticides (azinphos-methyl, chlorpyrifos, ethion, carbaryl, dicofol) were all highly toxic to H. velox, causing 100% mortality even at the lowest concentration. Avermectin and Provado® (a.i., imidacloprid) applied as sprays had moderate toxicity; whereas, Admire® (a.i., imidacloprid) applied as a drench and Tri-Basic® (copper fungicide) caused the lowest percent mortality (10-30%) even at the highest concentration. With a leaf-dip method, petroleum oil exhibited a low toxicity to H. velox. However, when combining petroleum oil with avermectin, a synergistic effect elevated the toxicity to moderate. Azadirachtin, Bacillus thuringiensis, and diflubenzuron showed low impact on H. velox . Less than 20% mortality was recorded at the highest concentrations for all of these products.

Trap crops and barrier crops are among the cultural control methods promoted for management of Bemisia argentifolii Bellows & Perring, particularly for small farmers in the tropics. In 1996 eggplant, Solanum melongena L., was tested as a trap crop, and in 1996 and 1997 corn, Zea mays L., was tested as a barrier crop for management of B. argentifolii on bean, Phaseolus vulgaris L. In 1996 treatments were compared by sampling immature B. argentifolii on bean leaves. Neither egg nor nymphal densities were reduced by eggplant or corn treatments in 1996. In the 1997 corn barrier trial plot size was increased and the orientation of barrier row to wind direction was evaluated. A dust-and-release procedure was used to measure entry of greenhouse-reared adult B. argentifolii into experimental plots. Counts from yellow sticky traps in 1997 indicated that migration by adult whiteflies into plots was determined primarily by air currents and was only marginally influenced by the presence of a corn barrier. The results indicate that barrier crops and certain trap crops may have limited value for whitefly management.