Abstract

                                Considerable work has been done on the physiology of drought resistance in crop plants. Most of the work, however, represents attempts to find some simple index of measuring drought resistance by means of easily observable anatomical or physiological characters. Studies of such physiological characters as water requirement, transpiration rates, bound water content, osmotic pressure and water balance are some of the popular aspects of approach to the problem of drought resistance. Among these characters, osmotic pressure and transpiration rate have been studied in great detail by many workers. Root studies have not received adequate attention owing to the difficulty in studying this underground part of the plant. The present studies relate to the above three characters in rice varieties which differ in their degree of drought resistance.

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