Lan Xu1, Arvid Boe2, Roger N. Gates3, and Patricia S. Johnson3. (1) Biology and Microbiology, South Dakota State University, Ag Hall 104, Box 2207B, Brookings, SD 57007, (2) Plant Science, South Dakota State University, SNP 244, Box 2140C, Brookings, SD 57007, (3) Animal and Range Sciences, South Dakota State University, West River Ag Center, 1905 Plaza Blvd., Rapid City, SD 57702-9302