Recent introduction and establishment of the leafroller parasitoid <i>Trigonospila brevifacies</i> (Hardy) (Diptera Tachinidae) in Nelson

Abstract

To assist the natural distribution of the leafroller parasitoid Trigonospila brevifacies to horticultural areas in the Nelson region 181 T brevifacies pupae and 329 adults were released in 1999 at four sites adjacent to apple orchards near Motueka Release material was supplied from fieldcollected parasitoids in Hawkes Bay and a laboratory colony held at the Mt Albert Research Centre in Auckland Successful establishment of the parasitoid was recorded at all four sites and at a nearby nonrelease site in 2000 In 2000 319 of fourth instar and older larvae were parasitised by T brevifacies while in 2001 parasitism was 1166 Important pest tortricid species including Epiphyas postvittana (Walker) (lightbrown apple moth) were among the hosts The successful establishment of T brevifacies in Nelson and its further natural dispersal will increase the potential for the reduction of economically important leafroller species by biocontrol agents