Characterization of blast resistance in the durably resistant rice cultivar moroberekan

摘要

Despite tremendous investment on blast research and control, blast remains one of the most widespread and destructive diseases of rice. Growing blast-resistant varieties is the preferred method for protecting rice from blast and for reducing the use of fungicides. Although resistance to blast is often short-lived, especially when resistance is conferred by single major genes, some cultivars possess durable resistance, as defined by Johnson (1981; Parlevliet, 1988). For instance, rice cultivars IR36, IR42, IR64, Milyangv30 and Milyang42 show durable resistance to blast under irrigated or rainfed lowland conditions. Moroberekan, ROKI6, LAC23, IRAT13, OS6 and some Brazilian upland rice cultivars show durable resistance to blast in upland conditions (Bonman and Mackill, 1988; Lee el al., 1989; Bidaux, 1978; Ahn, 1994; Fomba and Taylor, 1994). Characterization of the genetic basis of the resistance in these cultivars would provide insight into the durable resistance, and would be useful in designing genotypes with novel resistance.