Twenty wheat varieties varying in their drought tolerance were grown in the field under irrigated and unirrigated conditions. The leaf water spin-lattice relaxation time Tl measured at tillering stage of the crop grown under both conditions varied between 445–293 nis in the 20 varieties. In general, these values were higher for those varieties which were drought or heat tolerant. Biomass reduction under unirrigated conditions showed significant correlation with leaf water (T1) values confirming the positive association of T1 with drought tolerance in wheat genotypes.
