Gene Discovery and Pre-breeding in Cereals for Broad Resistance Against Insects Adaptable to Variable Environments

Climate change is expected to cause drastic changes in the incidence of disease and pests throughout the world, also leading to the occurrence of highly variable insect pests. One approach to minimize the losses in crop yields due to highly variable insects is the introgression of multiple resistance genes into adapted crop cultivars. The objectives of the study are to: 1) Identify wheat and barley germplasm from around the world that are resistant to various Russian wheat aphid biotypes in various countries, 2) develop genomic tools for marker-assisted breeding, and 3) introgress multiple resistance genes into more adapted wheat and barley cultivar. We have evaluated more than 80 wheat lines and over 200 barley lines from various parts of the world against a number of RWA biotypes from USA, Mexico, Hungary, France, Chile and Iran. Wheat and barley lines with moderate to good levels of resistance were identified. Genetic analysis of lines has revealed significant diversity. With the use of Doubled-haploid and F2:3 populations we have mapped resistance genes from various sources on chromosomes 1DS and 7DS in wheat, and 1H, 2H, 3H and 7H in barley. Closely linked SSR and Diversity array technology (DArT) markers have been identified, and these markers offer opportunities for marker-assisted breeding. The presentation will also outline the strategies for introgressing multiple resistance genes to adapted wheat and barley cultivars that could have better potential for minimizing yield loses due to increased incidence of insects because of climate change.