Molecular Marker Based Identification Of Diversity for Drought Tolerance in Wheat Cultivars (Triticum Aestivum L.)

Abstract

Wheat is the most Important staple food of about two b111ion people (36% of the wortd population) and demand for wheat is elCpected to grow faster than for any other maJor crop. Climate change is putting pressure on the resources we depend on increasing risks assoc1ated with disasters such as drought and floods. A rapidly growing and more affluent world population is increasing the demand for food commodities. Sustainable growth and diversification of food production with specific attention to productivity of small scale producers is needed W1th1n a contelC! of abiotic stresses particularly drought wh1ch affect the wheat crop production adversely and a major challenge for securing food security m India Cultivation of wheat in adverse climate condition IS one of the major challenges to attain sustamable food production. Eighty one wheat genotypes were assessed for water stress conditions using morpho-physic-biochemical and molecular tools. A set of eighty one wheat genotypes were used under normal sown in irrigated condition and non-irrigated conditions. Results revealed that post-flowering drought stress reduced the grain yield and Yield components in all genotypes. The highest yield loss was caused by the number of grain per spike and 1 OOQ-grain weight reduction under drought stress conditions The genotypes AKDW 2997-16. K 8027, K 8962 and NL 897/NL 724/IBL 2281 showed m1mmum decline and K 9006 and K 907 showed sharp decline for morpho and physiological as well as yield characters in stress at anthes1s. However, low to h1gh reductions were observed 1n stress conditions as compared to non-stress. In this study 45 SSR pnmers could be used to distinguish genetic vanation among 26 wheat genotypes. Among 45 primers only 10 primers showed highest polymorphism (100%) and 14 primer are monomorphic in nature. Ma.J<imum diversity was observed between AKAW- 4627 with K-9644 and K-8027 While least diversity was observed between UP-2425 and K- 9162. The presence or absence of DREB gene was first analysed at DNA level The varieties which showed the presence of DREB gene at DNA level were selected to characterize for the level of expression of transcnpt1on factor i.e. ORE elements However dreb-for2/rev1 oligo pair produced a band of 350bp in case of NL 897/NL 724/IBL 2281 while dreb- for21rev1 amplified a band of 250bp in case of AKDW 2997-16, K 8027. K 8962 and NL 897/NL 7241/BL 2281. After 5 days without water the intensity of bands was h1gher followed by slight decrease on 9 and 10 days respectively