Abstract only

The rusts are the most important biotic constraints to wheat production in Uzbekistan. Stripe (yellow) rust and leaf rust occur every year and cause substantial reductions in grain yield. Stem rust occurs in the foothills and flat-hilly zones with advancing crop maturity, but generally causes only limited yield reductions. The highest losses are caused by stripe rust. Both traditional and molecular breeding methods are used to improve rust resistance. The objective of the present study was to identify resistant genotypes; in Uzbekistan and Turkey for stripe rust, and in Kenya for Pgt race Ug99. Some varieties and advanced lines showed moderate to high levels resistance at all three locations. Markers were used to screen for the presence of Yr15, Sr22, Sr24, Sr26, Sr36 and Lr34/Yr18. According to marker data, 12 lines had Yr15, two lines Sr24, one line Sr26, four lines Sr22 and 49 lines carried Lr34/Yr18. Combined resistance was present in 12 newadvanced breeding lines. Agri/Bjy // Vee/3/Bul 6687.12, Co724377/Nac // Seri/3/Erythrospermum5678/87, and Zhetisu//Pyn/Bau/3/ 338-k1-1 // Anb/Buc from international nurseries, and ¹118\2004 and ¹144\2004 from local sources, were identified as high yielding rust resistant lines. This work identified potentially new varieties for release to farmers as well as useful information on effective rust resistance genes, or resistance sources, for breeders.

Global Wheat Program

English

Lucia Segura

INT1787

CIMMYT Staff Publications Collection