通过干旱胁迫处理测定了玉米、小麦及三叶草的土壤含水量、叶片含水量和叶片细胞膜透性.实验表明,当植物受到干旱胁迫时,质膜受到不同程度的破坏进而膜透性(电导率)增大;叶片含水量随土壤含水量下降而降低;在干旱胁迫下,越耐旱的植物,植物含水量下降越平缓,保水能力越强;不同作物保水能力从大到小依次为三叶草、玉米、小麦. The soil water content, leaf water content and leaf cell membrane permeability of maize, wheat and clover were determined by drought stress treatment.Experiments showed that when the plants under drought stress, the plasma membrane was damaged to some extent and the membrane permeability (conductivity) The water content of leaves decreased with the decrease of soil water content. Under drought stress, the more drought tolerant plants, the more the water content of plants decreased more slowly, the stronger the water retention ability. The order of water retention capacity of different crops was clover, corn ,wheat.