Studies on disruption of sexual communication in the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), with microencapsulated gossyplure or its component Z, Z-isomer

Abstract

AbstractMicroencapsulated gossyplure or its component Z,Z-isomer were applied to 0·04-ha field plots in Arizona for disruption of sexual communication in adults of Pectinophora gossypiella (Saund.). In an initial efficacy test, the materials were placed on cotton plants in 50-μl drops by hand at a rate of 3·7 g a.i./ha (24 690 drops/ha). Trap catches were reduced by averages of 92 and 81% for the Z,Z-isomer or gossyplure treatments, respectively, during a one-week test period. Mating in mini-mating stations was reduced by 100 and 91% for Z,Z-isomer and gossyplure treatments, respectively. In a further test, sprays were applied using a Micron Herbi 77 hand-held spinning disc applicator that was calibrated to deliver 1·97 × 108 spray droplets/ha (about 250 μm in diameter and 0·01 μl/drop). The spray and drop methods were used to apply rates of 2·5 or 12·3 g a.i./ha of both materials to 0·04-ha field plots. The 12·3 g/ha rate of microencapsulated materials was necessary to give about 90% reductions in trap catches for the 9–12–day test periods. Gossyplure and its Z,Z-isomer gave similar reductions in catches when the same rates and method of application were used. However, comparisons of results for 50-μl drops vs. spray indicated that the drops generally resulted in significantly lower trap catches than sprays at the 2·5 g/ha dose rate. The results indicate that spray application of microencapsulated gossyplure or its Z,Z-isomer have potential for communication disruption of P. gossypiella.