EFFECT OF BENZYLADENINE ON TRANSPIRATION, WATER POTENTIAL AND ITS COMPONENTS IN GENOTYPES OF WHEAT CONTRASTING IN DROUGHT TOLERANCE

Drought tolerant and susceptible cultivars of wheat, C-306 and Kalyan sona, growing under non-stressed and water-stressed conditions, were s prayed with benzyladenine (BA) at 70 days after sowing (DAS). Observat ions recorded at 5, 10, 15, 20 and 25 days after spraying revealed tha t BA increased the rate of transpiration (TR) in C-306 under non-stres sed conditions. However, under water stress, the increase was signific ant only after 5 days of BA spraying. In Kalyan sona BA treatment eith er decreased TR or did not exhibit significant increase under non-stre ssed conditions, but caused significant increase in TR under water str ess. The increase in TR was elicited through enhanced stomatal opening . Water potential, osmotic potential and pressure potential of both ge notypes decreased on account of water stress. The effect of BA was not perceptible on restoration of leaf water potential (LWP) or its compo nents. The effect of BA was possibly confined to stomatal behaviour an d transpiration.