EVALUATION OF SHIN-ETSU TWIST-TIE ROPE DISPENSERS BY THE MATING TABLETECHNIQUE FOR DISRUPTING MATING OF THE COTTON BOLLWORM, HELICOVERPA-ARMIGERA (LEPIDOPTERA, NOCTUIDAE), AND THE PINK-BOLLWORM, PECTINOPHORA-GOSSYPIELLA (LEPIDOPTERA, GELECHIIDAE)

Different Shin-Etsu twist-tie rope formulations, containing either the cotton bollworm, Helicoverpa armigera (Hubner) pheromone or pink boll worm, Pectinophora gossypiella (Saunders) pheromone, or both, in the s ame rope, were tested in Israel for mating disruption. The success of mating disruption was evaluated by the mating table technique, compari ng the percentage of mating of virgin sentinel females in pheromone-tr eated and control plots. Two variants of this technique were evaluated , one with two mating tables per plot, each containing five to sea en females, and the other with six to eight mating tables per plot, with only one female per table. The latter method was more sensitive than t he former, particularly at low population densities. Two tests were co nducted in 1995 in order to compare a blend of five components of H. a rmigera pheromone with a blend of two components for mating disruption . The application consisted of 2000 ropes/ha, each with 80 mg pheromon e. Evaluation by the two mating table methods showed clearly that the formulation containing two components was superior to the five-compone nt blend for mating disruption, suppressing mating almost completely f or 49 days. A new combined formulation, HPROPE, containing 175 mg of t he H. armigera two component blend and 65 mg of P. gossypiella pheromo ne was tested in 1996 for mating disruption of both pests. Application of 625 ropes/ha caused a high level of suppression of mating of H. ar migera females for at least 94 days and that of P. gossypiella females for 161 days. The pheromone release rates were c. 625 mg/day/ha for H . armigera and 162 mg/day/ha for P. gossypiella. A 'long-life' formula tion of P. gossypiella pheromone, PEW rope L(sic), applied at 125 rope s/ha releasing 137 mg/day/ha achieved complete suppression of mating o ver 75 days. This release rate of P. gossypiella pheromone was much lo wer than that currently used in Israel (275 mg/day/ha). The present st udy indicates that mating of females of two moth pests with different pheromones can be disrupted by one combined formulation.