Virus-like particles in the ovaries of Microctonus aethiopoides Loan (Hymenoptera : Braconidae), a parasitoid of adult weevils (Coleoptera : Curculionidae)

The morphology of the female reproductive system of Microctonus aethiopoide s is described and illustrated, and an ultrastructural examination of the o varies was carried out. Virus-like particles (VLPs) were initially found in the ovarial epithelial cells of females from pre-adult emergence from the pupal cocoon until at least 5 days after emergence. The particles assembled in the nucleus of the epithelial cells, apparently being synthesized de no vo in association with a putative virogenic stroma, and they moved into the lumen of the ovarioles surrounding the developing eggs, VLPs were also fou nd in some other cells in both male and female M. aethiopoides. VLPs have n ot been found in M. hyperodae or the New Zealand native species M. zealandi cus. The function of the VLP and its possible role in potential parasitoid host range determination are discussed. (C) 1999 Academic Press.