Barley Germplasm Resistant to Both Russian Wheat Aphid and Greenbug.

Both Russian wheat aphid, Diuraphis noxia (Kurdjumov), and greenbug, Schizaphis graminum (Rondani) are potential pests on winter cereals grown in the southern plains.  In outbreak years, both aphids can drastically reduce grain yield of susceptible cultivars.  In barley, two single dominant genes, Rsg1 and Rsg2, confer resistance to the most prevalent biotypes of greenbug.  Greenbug-resistant winter barley cultivars are available to growers in the southern plains.  There are no RWA-resistant winter barley cultivars for the US.  RWA resistance from  8 different sources was transferred by backcross breeding into Post 90, a high yielding, greenbug resistant cultivar with Rsg1 resistance.  Promising lines breeding true for resistance to both aphids were evaluated for agronomics in Idaho and Oklahoma.  Eight germplasm lines, STARS 1006B – STARS 1013B, with grain yield equal to or greater than the recurrent parent, Post 90, have been released.    Each line carries RWA resistance from one of 8 different sources as well as Rsg1 greenbug resistance.