Genetic diversity of spring wheat from Kazakhstan and Russia for resistance to stem rust Ug99 uri icon

abstract

  • The spring wheat belt of Western Siberia and Northern Kazakhstan covers more than 15 million ha. While moisture stress is the main factor limiting production, rusts also represent a major challenge, especially in years with higher rainfall. Stem rust was not considered economically important until 2015 when a local epidemic occurred in the Omsk region of Russia and neighboring areas of Kazakhstan and affected more than 1 million ha. It occurred again in 2016 though the spread, severity and losses were less. This study used 16 pathotypes and 17 molecular markers to characterize a set of 146 spring wheat varieties and breeding lines identified as stem rust resistant in Kenya and the Kazakhstan-Siberia region for the presence of major genes. The genetic basis of resistance in the material was limited to Sr25, Sr31, Sr36, Sr6Ai, Sr6Ai#2, and some unknown major genes. Genes Sr25 and Sr6Ai#2 also provided high levels of resistance to leaf rust through linkages with Lr19 and Lr6Ai#2. Adult plant resistance to stem rust was observed in 26 genotypes (16.5 %), including eight possessing Sr57 gene. The high risk of stem rust-as indicated by the 2015 Siberian epidemic-means that there is an urgent need to diversify the genetic bases of resistance and to promote resistant varieties with farmers.

publication date

  • 2016
  • 2016