低温胁迫对烟草保护性酶类及氮和碳化合物的影响

Effects of Low Temperature Stress on the Protective Enzymes and Contents of Nitrogen and Carbon Compounds of Tobacco Seedlings

在6℃和10℃低温胁迫下,研究了2个烟草品种的膜透性、保护性酶类活性和N,C化合物含量的变化.结果表明:2个烟草品种幼苗的膜透性都随着胁迫温度的降低和胁迫时间的增加而增加;酶活性的变化趋势为:CAT和SOD随着胁迫温度的降低和胁迫时间的增加而降低,POD的变化则有相反的趋势;蛋白质含量在低温胁迫下下降,脯氨酸含量则增加,并且脯氨酸在叶片中的变化较为剧烈;可溶性总糖和蔗糖含量低温胁迫下在叶片中有所积累,而叶绿素a、叶绿素b和叶绿素总量则可能因叶绿体受损而下降.

Changing of membrane permeability, protective enzyme and content of N, C compound were studied under 6℃ and 10℃ low temperature stress. The results showed that membrane permeability of two tobacco variety seedling increased as the stress temperature decreased and stress time increased. Changing of enzyme activity was that CAT and SOD activity reduced because of the increase of low temperature stress time and decrease of temperature. However, it was contrary to the POD. As regard to the content of protein and proline, the former decreased while the latter increased by low temperature stress. But the changing of proline in leaf was more greatly. Total content of soluble sugar and sucrose accumulated in leaf and content of chlorophyll, chlorophyll b and total chlorophyll reduced due to the damage of chlorophyll corpuscle under low temperature stress.