Virus-like particles in testes of Heliothis virescens, H. subflexa, and backcross males derived from the hybridization of H. virescens males X H. subflexa females

Testes of adult Heliothis virescens, H. subflexa , and backcross males derived from crosses between H. virescens males and H. subflexa females were examined for the presence of virus-like particles (VLPs). These spherical 45- to 50-nm VLPs were first detected in spermatocyst cells of H. virescens embedded in plastic resin 4 years previously. Abnormal spermatocysts with degenerating sperm were present in testes of all three groups and were accompanied by massive accumulations of VLPs within the spermatocyst cell cytoplasm. The degree of spermatocyst infection was age dependent in the parent species, with young males having a low incidence (4-8%) and older males (2-3 weeks) exhibiting up to 90% abnormal spermatocysts. Backcross males showed 100% infection at 2 days posteclosion.