Effect of Barley yellow dwarf virus Infection on Yield and Malting Quality of Barley.

Barley yellow dwarf virus (BYDV) infection occurs frequently in barley in the Upper Midwest region of the United States; however, the impact of this disease on the yield and quality of malting cultivars has not been adequately addressed. Studies were conducted at Fargo, North Dakota (from 1989 to 1990) to determine the effect of BYDV infection on yield and malt quality parameters in barley. Three malting cultivars varying in yield potential and malting characteristics were artificially inoculated at the seedling stage with a North Dakota BYDV isolate of the PAV serotype. Overall yields were reduced 32.5 to 38% in 1989 and 8.5 to 19.8% in 1990 by BYDV infection. Thousand-kernel weight (3.2 to 14.9%) and kernel plumpness (11.9 to 38.9%) also were reduced. Kernel color and three malt quality parameters (α-amylase, malt recovery, and wort viscosity) were not affected by BYDV infection. Increases in wort protein (2.5 to 14.5%) and diastatic power (3.8 to 12.6%), and decreases in malt extract (1.1 to 5.6%) were found. Most notably, total protein increased 4.6 to 17.5% with BYDV infection. Higher proportions of thin seed, as a result of BYDV infection, contributed to the effects on several quality parameters. In summary, the negative effect of BYDV infection on overall quality is significant and should be considered when assessing the impact of this disease. Although annual BYD disease-related losses are typically not extensive in the Midwestern malting barley region, the incorporation of host resistance into recommended cultivars would ameliorate the negative effects of BYD disease on crop quality as well as on yield.