Assessment of D-genome Based Genetic Diversity in Drought Tolerant Wheat Germplasm

The complex nature of drought stress is one of the key bottlenecks in wheat improvement.Besides conventional breeding approaches for wheat improvement under water deficit conditions use of wild relatives like Aegilops tauschii (DD), as a source of rich genetic variation has significantly triggered the process.In this study, we have assessed the D-genome based genetic diversity in drought tolerant germplasm by using SSR markers.A total number of 178 alleles were detected on 49 loci with an average of 3.49 alleles per locus with the highest number being of 10 alleles for marker gwm515-2D.Genetic diversity explained by these SSR makers ranged from 4 to 67% with an average of 56.2% per marker.There were 23 SSR markers, which revealed PIC (Polymorphism Information Content) values of more than 50% while overall the PIC values for all markers ranged from 8 to 63.2% with an average of 48.1%.Clustering of genotypes D41, D43, D44, D50 and D51 within two well-known drought tolerant cultivars viz.Dharwar Dry and Sitta showed the suitability of these genotypes for water deficit areas.In conclusion, the genetic diversity present in the studied germplasm may be used in wheat breeding programs targeted for the drought tolerance especially in arid/semi-arid (rain-fed) environments.