The objective of this research was to verify the behavior of Bemisia tabaci (Gennadius) biotype B (Hemipetra; Aleyrodidae) in systems with coriander (Coriandrum sativum L.) associated with melon (Cucumis melo L.) and watermelon (Citrullus lanatus Thumb. Mansf.). The essays were set in a greenhouse in Fortaleza between 2003 and 2004 in a completely randomized design with four replicates. Watermelon experiments associated with coriander and melon were accomplished this way: fourteen days after planting the watermelon, they were arranged in a cage and then released 50 adults of whiterflies per plant. Those plants were uninfested five days later. The same process was used for melon with coriander. Treatments were evaluated when watermelon and melon plants were with 25 days by cutting a circular area of 2.8 cm2 of the four oldest leaves of each melon, watermelon plants, and 3 coriander leaves, and then all nymphs were recorded. We confirmed that melon was the least chosen by whitefly insect in presence of coriander. On the other hand, in a restricted environment coriander associated with watermelon, was the least favorite plant, and could be responsible to elicit a hormoligosys process.
