Reaction of a Diverse Collection of Barley Lines to Fusarium Head Blight.

Fusarium head blight (FHB) is currently the primary disease of concern in barley in Canada and sources of FHB resistance need to be identified. A diverse collection of 77 two-rowed and 81 six-rowed barley lines was screened for resistance to FHB in inoculated, irrigated nurseries from 1995 to 1998. Barley spikes were spray inoculated with conidia of Fusarium graminearum and visual symptoms of FHB were scored to determine an FHB index. Deoxynivalenol (DON) content was determined from harvested seed samples during 1997 and 1998. Although there was variation in the average FHB index and DON content among the different years of testing, the rankings of the lines generally were correlated among the years of testing and the two measures of FHB. Based on the FHB index from 1995 and 1996, a subset of 18 lines with low FHB and 12 lines with high FHB were compared with 20 FHB resistance sources and 7 Canadian lines or cultivars during 1997 and 1998 in both inoculated and noninoculated nurseries. Lines Nepolegajuscij, Krasnojarskij, Nordic, Murakaki-mochi, Golozernyj 1, Maris Mink, Symko, Ussurijskij 8, Suvenir, and Canadian cultivars AC Sterling and Morrison were similar to the best resistance sources (Zhedar1, Seijo II, and Chevron) and had consistently low DON content.