一、Freezing ( frost )injure
（一）Mechanism of freezing (frost )injure 1.Freezing：
Freezing in intercellular――细胞间隙结冰。。 Intracellular Freezing——胞内结冰。 2. damage of protein——二硫键假说。 3.Damage of biomembrane （二）、Chilling injure 1. Change in state of lipid
2. Metabolism disorder：青枯死苗（水稻）和黄枯死苗。 （四）、Methods to increase the resistance to low temperature. 二、 High temperature stress and heat resistance of plants. （一）、Reasons for heat injure 1. Indirect damage 2. Direct injure
二、Mechanism of heat resistance
High contents of saturated fatty acid和organic acid。 heat shock proteins
Section3 Salt stress and resistance to salt
1. 生理干旱。 2. 单盐毒害。 3. 破坏正常代谢。 二、抗盐性机理
泌盐。稀盐。拒盐。耐盐。