Registration of 'RWA 1758' Russian Wheat Aphid-Resistant Spring Barley

'RWA 1758' (Reg. No. CV-336; PI 648913) is a spring, Russian wheat aphid (Diuraphis noxia Mordvilko) (RWA)-resistant two-rowed barley (Hordeum vulgare L.) developed by the USDA-ARS. RWA 1758 was selected and released on the basis of competitive agronomic performance and resistance to damage caused by RWA feeding. RWA 1758 derives from a BC(3) F(3:4) selection from the cross 'Baronesse'*4/STARS 9577B. It was tested under the experimental designation 01ST1758. STARS 9577B is a six-rowed spring RWA-resistant germplasm line developed and released by the USDA-ARS. STARS 9577B is resistant to the five RWA biotypes known to be present in the United States. STARS 9577B was developed via selection from Clho 4165, a landrace originally collected in Afghanistan. The main component of the resistance is tolerance, conferred by two dominant genes with recessive epistasis.