Der Parasitenkomplex des Heckenwicklers, Archips rosana (Linné), im Havelländischen Obstbaugebiet.

Abstract

The investigation of the parasite complex of the apple leafroller Archips rosana (L.) in the „Havelländisches Obstbaugebiet", GDR, revealed 18 species, which have been reared from caterpillars and pupae. The most common species of the parasite guild are the hymenopterans Itoplectis maculator (F.) and Phytodietus segmentator (Grav.). They were collected in almost all orchards of the fruit-culture district. The other species including 4 tachinids occurred locally and are of minor importance. Egg parasites such as Trichogramma spec. could not be detected in the field, neither in unsprayed nor in sprayed orchards. In order to ascertain the percent parasitism of A. rosana (L.) an orchard was selected, which remained unaffected by insecticidal applications. The percent parasitism reached 28,9%. It is supposed, that the percentage of parasitism remained below 28,9% in the normally sprayed orchards. The parasite complex must probably regarded as of secondary importance for the A. rosana dynamics in apple orchards.