Pink Bollworm: Response of Released APHIS Strain and Native Moths to Ratios of Z,Z and Z,E Isomers of Gossyplure in the Field123

Abstract

Native male Pectinophora gossypiella (Saunders) showed a statistically significant preference for bait containing 60% of the Z,Z isomer of gossyplure and 40% of Z,E isomer early and late (May and Oct., respectively) in the 1977 cotton-growing season in Phoenix, AZ. The same preference was shown by released irradiated moths produced by the Animal and Plant Health Inspection Service (APHIS), USDA (same production released in the San Joaquin Valley of California during the 1977 season). During the intervening months, the 50% baits caught as many or more of both types of moths than the 60% baits. Early in the season, the 50 and 60% baits accounted for 78% of the total catches of native males; in Aug., the comparable catch was 34%, indicating an increased acceptance of less than optimum ratios during mid-season. Recovery of APHIS moths ranged from 0–29% during the season; lowest recoveries occurred in Aug. and Sept. when native populations were greatest.