Aspects of the Effect of ABA on the Water Status of Barley and Wheat Seedlings

Abstract

Abstract The effect of abscisic acid on plant growth and survival during water deprivation was studied in barley and wheat seedlings. Under conditions of both limited and ample water supply, treatment with abscisic acid greatly reduced transpiration and, in addition, suppressed root growth. In water‐deprived seedlings, abscisic acid increased the total dry matter, reflecting improved efficiency in water‐use. In addition, the growth period and survival of water‐deprived seedlings were markedly prolonged. In field trials, however, abscisic acid had no significant effect on waterdeprived seedlings. Possible reasons for this lack of response are discussed.