A Virginia Tech horticulturalist has received a $1 million grant from the National Institute of Food and Agriculture to develop rust-resistant switchgrass varieties.

The fast-growing warm-season perennial is seen as a potential feedstock for cellulosic ethanol production, but it could be devastated by a rust fungus that has been identified as Puccinia emaculata Schwein, says Bingyu Zhao. He and his colleagues have already identified several rust-resistance genes in a collection of 2,000 switchgrass plants at Virginia Tech’s Kentland Farm.

“A potential virus-induced gene-silencing tool for quickly analyzing the function of rust-resistance genes in switchgrass has been developed,” says Zhao. “The aim is to breed broad- spectrum rust-resistant switchgrass cultivars that could be strategically deployed according to the local rust pathogen population to ensure the large-scale and sustainable biomass production in the future. Deployment of host resistance genes guided by rust population genetics information is the best practice to durably and sustainably protect switchgrass feedstock production against rust infection.”

In 2009, Zhao received a $1 million award from the National Science Foundation for his research on a disease-resistant gene in corn that will prevent bacteria from invading distantly related plant species. His work could help plant breeders transfer resistance genes from model plant species into important crop plants.

Co-investigators on the switchgrass project are Brett Tyler, Virginia Tech plant pathologist; Stephen Marek and Carla Garzón, Oklahoma State University plant pathologists; and Bing Yang, Iowa State University plant geneticist.