Control of <i>Epiphyas postvittana</i> (lightbrown apple moth Lepidoptera Tortricidae) on grapevines with tebufenozide

Abstract

Feeding by leafroller larvae damages grape bunches and makes them susceptible to Botrytis cinerea disease Leafroller infestation of foliage and bunches and the incidence of botrytis was measured on vineyards in Gisborne Hawkes Bay and Marlborough over 2 years Fortyfour blocks received no leafrolleractive insecticides while 22 were sprayed once preflowering with the selective insect growth regulator tebufenozide Tebufenozide very effectively reduced infestations and gave seasonlong control On leaves untreated blocks averaged 14 leafrollers/search compared with 4 on sprayed blocks Comparative figures for fruit at harvest were 18/100 bunches and 3/100 respectively There was a trend for lower botrytis incidence in blocks where tebufenozide was used Over 99 of the leafrollers reared were Epiphyas postvittana Parasitism of larvae and pupae at 67 on leaves and 50 in bunches was similar in untreated and treated blocks Epiphyas postvittana in vineyards is easily managed using tebufenozide which did not compromise biological control