WATER RELATIONS IN WHEAT LEAVES AS SCREENING TESTS FOR DROUGHT RESISTANCE

Abstract

Relative saturation deficit, water content and water retention ability of wheat leaves were investigated as possible tests for drought resistance. The drought tolerant Pitic 62 showed the lowest relative saturation deficit at low soil moisture stress but not at high soil moisture stress. Water content was highest in Pitic 62 throughout the soil moisture range. Analysis of individual plants from a population of Pitic 62 and ACEF-125 and their hybrid showed a greater differential between the genotypes for water content than for relative saturation deficit. Selection was effective for water content but not for relative saturation deficit. Water retention ability after a 24-h drying period varied considerably among the five cultivars examined, with Pitic 62 and Pelissier being the best water retainers. Position of leaf and stage of maturity affected water retention ability. Pitic 62 appeared to contribute the dominant genes for water retention ability and water content in a hybrid from a cross with ACEF-125.