Abstract

IPCC has predicted increase in drought and heat affected areas under wheat. To combat this challenge, development of heat and drought tolerant wheat genotypes is on priority. Landraces are unexploited genetic resources for various agronomic traits contributing tolerance to abiotic stress. Twenty-one wheat genotypes were evaluated in irrigated timely, rainfed timely and irrigated late field conditions for two years for their response to drought and heat stress. Genotypes differed significantly in their response to 1000-grain weight under stress conditions. Stress susceptibility index (SSI) was used to identify drought and heat tolerant genotypes. Nine genotypes were tolerant to drought stress and 11 to heat stress. Six of these genotypes were tolerant to both the stresses. SSR and allele specific markers were used to validate the results. Allelic variation for heat tolerance was observed in two genotypes IC 36761A and IC 41504 with gwm 63. Similarly, SNP marker for distinguishing drought tolerance in bread wheat was used and bi-allelic variation with this primer was observed in genotypes IC 57586, IC 30276A, IC 36761A and IC 31405B. IC 36761A was tolerant to both the stresses and was differentiated using molecular markers also. This genotype can be used for breeding drought and heat tolerant cultivars.