Enveloped, prolate ellipsoid form (ichnoviriform) and cylindrical (bracoviriform). Depending on the species, a virion contains one or several nucleocapsids.
Segmented, circular supercoiled dsDNAs ranging from 6.0-20kb. Each virion contains multiple copies of the genome.
a) replicative: occurs in the calyx cells of the ovary.
- Excision and circularization of viral DNA in the ovary cells.
- Viral DNA synthesis.
- Appearance of viral envelopes and nucleocapsids in the nucleus.
- Mature virions are released into the lumen of the oviduct probably by lysis (brachoviriform) or budding through the cell membrane (ichnoviriform).
b) vegetative: occurs in all non-reproductive cells.
The viral genome is transmitted in proviral linear form integrated in the wasp's chromosomes. The virus DNA is replicated, just like any other part of the wasp's genome.