Potential of field corn as a barrier crop and eggplant as a trap crop for management of Bemisia argentifolii (Homoptera : Aleyrodidae) on common beanin North Florida

Trap crops and barrier crops are among the cultural control methods promote d for management of Bemisia argentifolii Bellows & Perring, particularly fo r 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 vulg aris L. In 1996 treatments were compared by sampling immature B. argentifol ii on bean leaves. Neither egg nor nymphal densities were reduced by eggpla nt 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 evaluat ed. A dust-and-release procedure was used to measure entry of greenhouse-re ared adult B. argentifolii into experimental plots. Counts from yellow stic ky traps in 1997 indicated that migration by adult whiteflies into plots wa s determined primarily by air currents and was only marginally influenced b y the presence of a corn barrier. The results indicate that barrier crops a nd certain trap crops may have limited value for whitefly management.