Abstract: The major components of fatty acids of the membrane Lipid in wheat (Triticum aestivum L.) are palmitie 16:0), paimitoleic (16:1), stearie (18:0), oleeic (18: 1), linoleic (18:2) linolenic acid (18:3) and a few others. Of the total fatty acids, palmitic, linoleie and linolenic acid are predominant in amount. Under the condition of high temperature and low humidity the contents of palnfitie and oloie acid in the membrane lipids increased and the linoleic and linolenie acid decreased, which resulted in high degree of saturation of membrane fatty acid. It was found that the influence of high temperature on the fatty acid compositions was stronger than that of low humidity. Two winter eultivars showed different in their resistance to high temperature and low humididty, and a difference in degree of saturation of membrane fatty acid Was also detected. The resistant eultivar possessed a higher degree of staturation of fatty acid than the sensitiveone. Similar trend was obtained from various oultivars to high temperature and low humidity. This seems to be a corelation between the resistivity of wheat cultivar to high temperature and low humidity and the degree of saturation of membrane fatty acids.

Key words: winter wheat, high temperature and low humidity, membrane fatty acid