Associations between plant production and some physiological components of drought resistance in wheat

Abstract

Abstract. Drought resistance in terms of plant production under conditions of drought stress was previously defined for several spring wheat ( Triticum aestivum L.) varieties. Four varieties, differing in their drought resistance by this definition, were compared in their physiological responses to water stress, as induced by polyethylene glycol 6000 in the growth medium. Drought resistance was associated with osmotic adjustment, total root mass production under stress, maintenance of some stomatal permeability under stress, and maintenance of turgor at a given level of drought stress, by either osmotic adjustment or elevated plant water potential. Drought resistance was not associated, in this experiment, with plant top growth under stress or non‐stress conditions, maximum leaf area per plant, plant transpiration, and total root mass production under non‐stress conditions.