Effects of Mildew and Nitrogen on Grain Yield of Barley Artifically Infected in the Field

Powdery mildew was artificially introduced into field plots of barley given two amounts of nitrogen fertilizer. In Tyra and Triumph, grain dry matter and nitrogen yield of healthy plots increased in response to nitrogen fertilizer. In mildewed plots increases in response to nitrogen did not occur in Triumph, despite low levels of mildew infection. Mildew reduced grain yield and nitrogen content at both levels of nitrogen in both varieties.