1. Insect Chemical Ecology Laboratory, Plant Sciences Institute, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Maryland 20705, Subtropical Agricultural Research Laboratory, Crop Quality and Fruit and Insects Research, Agricultural Research Service, U.S. Department of Agriculture, Weslaco, Texas 78596, and Mission Methods Development Center, APHIS, PPQ, U.S. Department of Agriculture, Edinburg, Texas 78539