Mating disruption of the Japanese giant looper in tea gardens permeated with synthetic pheromone and related compounds

Abstract

Abstract The Japanese giant looper, Ascotis selenaria cretacea , is a serious defoliator of tea gardens in Japan. The females produce racemic ( Z,Z )‐6,9‐ cis ‐3,4‐epoxynonadecadiene (epo3,Z6,Z9‐19:H, main component) and ( Z,Z,Z )‐3,6,9‐nonadecatriene (Z3,Z6,Z9‐19:H, minor component). The orientation of the males to the synthetic pheromone placed in a trap was strongly disrupted by Z3,Z6,Z9‐19:H or a mixture of its monoepoxy derivatives (epoxydiene mixture, EDM) impregnated in septa and placed around the trap. Based on this result, polyethylene tubes containing Z3,Z6,Z9‐19:H or EDM were prepared and effect of these dispensers was examined in a field. Disruption of male orientation to synthetic pheromone traps was achieved in orchards permeated with Z3,Z6,Z9‐19:H at dispenser density of 3000 and 5000 tubes ha −1 (release rate: 0.55–0.61 mg day −1 tube −1 ) and with EDM at every tested dose, 250–5000 tubes ha −1 (release rate: 0.25–0.39 mg day −1 tube −1 ). Furthermore, disruption of mating in tethered females was observed in these orchards; particularly, the mating was perfectly inhibited in the areas treated with EDM at 3000 and 5000 tubes ha −1 . This is the first formulation for the mating disruption of a geometrid pest.