Evaluation of Orchardgrass Varieties for Foliar Disease Susceptibility.

With the increasing importance of high quality hay in the Northeast commodity market, a healthy, high yielding orchardgrass variety that is naturally resistant to foliar disease helps to ensure an attractive, profitable product.  This evaluation summarizes the data collected from the 2006, 2007, and 2008 growing seasons of an ongoing disease evaluation of 17 varieties of orchardgrass and 2 varieties of perennial ryegrass grown at the Russell E. Larson Agricultural Research Farm, Rock Springs, PA.  Percent disease severity (0- no disease, 100- all tissue diseased) of each variety was collected by visually assessing the amount of diseased foliar tissue in the complete plot at three times during the growing season, representing early, mid, and late season harvest.  The principle disease that was observed is brown stripe of orchardgrass, caused by the fungus Cercosporidium graminis, which causes premature tip dieback and reduces the quality of dry hay.  The 5 varieties with the least diseased foliage included Barlemas, LG-31, Tekapo, Athos, and OG 9704.  The 5 varieties with the highest diseased tissue included Persist, Takena 2, OG 9701, ECF 30, and Pennlate.  Extend was one of the higher yielding varieties that exhibited low diseased tissue.