“…Hypovirulence in plant pathogenic fungi can be caused by several infectious cytoplasmic factors, including viruses, virus-like agents, and plamids (Elliston, 1982), but most commonly, hypovirulence has been associated with double-stranded RNA (dsRNA) genetic elements. The hypovirulence-associated mycoviruses in several plant pathogenic fungi have been characterized and classified into five virus families, the Chrysoviridae, Hypoviridae, Narnaviridae, Reoviridae, and Totiviridae, based on genome structure, particle morphology, or absence of an encoded coat protein (Buck, 1998;Hillman et al, 2000;Wickner et al, 2000;Ghabrial, 2002;Nuss, 2005).…”