The seasonal abundance of the newly established parasitoid complex of the Eucalyptus tortoise beetle ( Paropsis charybdis)

Abstract

Enoggera nassaui has been the key biological control agent of the eucalyptus tortoise beetle Paropsis charybdis since 1987 In 2001 a second egg parasitoid Neopolycystus insectifurax as well as an obligate hyperparasitoid of E nassaui Baeoanusia albifunicle were detected in New Zealand Monitoring of Eucalyptus nitens plantations in the central North Island revealed that 50 of P charybdis eggs in half the sites were parasitised by E nassaui in early summer However later in the season this was followed by a reduction to 10 parasitism by E nassaui the remaining 40 of parasitised eggs being hyperparasitised by B albifunicle Neopolycystus insectifurax parasitised an additional 35100 of eggs in late summer This indicates that while B albifunicle has the potential to severely reduce the effectiveness of E nassaui the new agent N insectifurax is a promising alternative