A new race of stripe rust adds another element of risk for Texas wheat producers who now have fewer resistant varieties available to help battle the devastating disease.

That’s according to Robert Duncan, Texas AgriLife Extension agronomist and small grains specialist, who said the new race of stripe rust caused yield loss in varieties that were previously resistant.

“Jagger and Jagalene now exhibit a susceptible reaction,” Duncan said during the recent Texas Plant Protection Association annual conference in College Station. Only three hard red winter varieties, Fannin, Doans and TAM 111, remain resistant.

“Management will require an integrated approach including use of resistant varieties and fungicide applications,” Duncan said. He and others are looking at best management practices to combat the new threat to wheat yields.

Part of that effort includes examining “the interaction between host resistance and fungicide application timing,” Duncan said. They used four varieties—TAM 111, TAM 112, TAM 304 and Fannin—along with multiple fungicide timings to identify best programs for stripe rust management.

“TAM 111 is resistant to stripe rust but not leaf rust,” Duncan said. Texas wheat growers often have problems with both.