Effect of Some Antitranspirants on growth and yield of wheat plants under limited irrigation

Abstract

A pot experiment was carried out to study the effect of 3 irrigation intervals (7, 14, 21 days) and two antitranspirants (Abscisic and Phenylmercuric acetate) on some growth, physiological and anatomical· characters of wheat plants . It has been found that the increase in water stress by gradual increasing of irrigation intervals the growth criteria reduced gradually (Shoot length, fresh and dry weights, Oag leaf area, and root fresh and dry weights), while root length was increased. Also, there was a reduction in stomatal opening, shoot water content and relative turgidity by water stress In addition, T. carbohydrate content, T. protein in shoots and grains were decreased but proline content was increased by water shortage . The mineral ions have been also decreased . The anatomy of leaves alkt"ted however, stomatal chambers, thickness of lhl l'pidermal cclh,, size of the hinge cells, mid rib diameter and the mean distance between the vascular bundles were decreased .

The antitranspirant (ABA) decreased the growth criteria causing a reduction in water loss but not affected the photosynthesis rate . ABA improved the yield of wheat plants and water relations . In addition, ABA decreased proline content while T. carbohydrates and T. proteins of grains as well as mineral ions (N,K and Na) were increased in shoots and grains .

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Spraying plants with PMA decreased the growth criteria, yield and yield components . Also, T. carbohydrates, T. protein and mineral ions content (N,K, and Na) m shoots and grains were decreased by PMA application .

With the anatomical studies the two antitranspirants decreased the stomatal opening, stomatal chamber, thickness of mesophyll tissue and the thickness of epidermal cells, but increased the mid-rip diameter and the main distance between vascular bundles in proportion to the nag leaf area .