First report of rust on switchgrass (Panicum virgatum) caused by Puccinia emaculata in Tennessee.
In the spring of 2007, switchgrass (Panicum virgatum) accessions and cultivars Alamo, Kanlow, SL-93-2001 and NSL 2001-1 (lowland), Blackwell (upland), and Grenville, Falcon and Miami (unknown ploidy levels) were sown in Tennessee, USA, for evaluation and controlled hybridization. In July and August of 2007, uredinia were observed primarily on the upper leaf surfaces, and to a lesser extent on the undersides of leaves, of switchgrass cultivars Alamo, Blackwell, Grenville, Falcon, Kanlow and Miami. Uredinia were observed on all cultivars and accessions in 2008. The pathogen was identified as Puccinia emaculata. This is thought to be the first report of P. emaculata on switchgrass in Tennessee.