Wheat farmers may soon have a new tool to fight a devastating plant disease, wheat streak mosaic virus.

Texas A&M AgriLife Research scientists in Amarillo, including Dr. Shuyu Liu, small grains geneticist; Silvano Ocheya, doctoral graduate student in College Station; Dr. Jackie Rudd, wheat breeder; and Dr. Qingwu Xue, crop stress physiologist are developing genetic diagnostic markers to identify wheat streak mosaic virus resistance.

Those markers will provide wheat breeders a new tool in breeding wheat varieties resistant to one of the region’s most prevalent diseases.

They were joined by Dr. Guorong Zhang, wheat breeder at Kansas State University Agriculture Research Center at Hays, Kan.; and Dr. Guihua Bai, U.S. Department of Agriculture-Agricultural Research Service Central Small Grain Genotyping Center at Manhattan, Kan.

Wheat streak mosaic virus, which is transmitted by wheat curl mite, is one of the major limiting factors for wheat production in the Southern High Plains, Liu said. The yield loss can be up to 50 percent due to wheat streak mosaic virus in any given epidemic year.

There are several resistance genes to wheat streak mosaic available, but only one gene, labeled Wsm2, is from a wheat line, he said. The other two are from wheat relative species. Wsm2 has been bred in two wheat cultivars, RonL and Snowmass. This resistance gene is now being used by breeders in Kansas, Colorado and Texas to combine with other traits.

Ocheya, funded by Monsanto Beachell Borlaug Scholarship, is using a wheat population derived from CO960293-2 and TAM 111 to map the drought tolerance genes in TAM 111 and identify tight linked single nucleotide polymorphic or SNP markers, for drought tolerance genes and Wsm2. SNPs are variations within the DNA.

More on TMU study.