VATIS UPDATE Article

Dazhong “Dave” Zhao, at University of Wisconsin-Milwaukee (UWM), the United States, hopes to build a genetic sterility switch that prevents the modified grass from contaminating the genes of nearby unmodified grasses. Switchgrass is an attractive biofuel feedstock because it can grow on marginal lands of little agricultural value. It also requires less chemical fertilizer than corn, the dominant source of ethanol currently mixed into unleaded gasoline.

“Grasses can grow anywhere and are not in competition with human food production,” said Zhao. In addition to being a low-input and fast-growing crop, switchgrass can survive for 10 years or more, while corn must be sown at the start of each growing season. Last but not least, switchgrass greatly reduces erosion by holding soil in place while providing habitat for birds, insects and other wildlife.

To make biofuel production more sustainable, Zhao and team are tackling the main obstacle keeping genetically modified switchgrass off the commercial market. Zhao is testing this method in Brachypodium distachyon, a model grass very similar to switchgrass. He has already demonstrated that his fusion gene, works well in tobacco and Arabidopsis, a flowering plant commonly used as the first test case for genetic modifications. If the fusion gene works well in the model grass, Zhao plans to collaborate with USDA scientists on testing it in switchgrass.