苗期夜间低温处理对番茄叶片蔗糖代谢的影响

Effects of Low Night Temperature on Sucrose Metabolism in Seeding Tomato Leaves

[目的]探讨夜间低温处理对番茄叶片蔗糖代谢的影响。[方法]以夜温15℃为对照,设夜温6℃(18:00～6:00)为处理,处理7d后测定番茄叶片糖和淀粉含量及蔗糖代谢相关酶活性。[结果]夜间低温处理增加了叶片中的果糖、葡萄糖、蔗糖、总糖和淀粉的含量,果糖和葡萄糖含量与对照相比差异不显著,蔗糖、总糖和淀粉含量与对照相比差异达极显著水平;夜间低温处理增加了叶片中酸性转化酶(AI)和中性转化酶(NI)活性,降低了蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性。[结论]夜间低温导致番茄叶片中光合产物积累,对光合作用产生反馈抑制。

[ Objective J To explore the effects of low night temperature on sucrose metabolism in tomato leaves. [ Methods ] Treatment was set up： 6℃ treatment over night（ 18：00 -6：00） for 7 days, using 15℃ as control to determine the content of sucrose and starch in tomato leaves and the relative enzyme activity of sucrose metabolism. [ Results ] Contents of fructose, glucose, sucrose, total sugar and starch were increased in tomato leaves under low night temperature. Contents of fructose and glucose were no obvious difference compared with control, contents of sucrose, total sugar and starch were very significantly different between control. The activities of acid invertase （AI） and neutral invertase （NI） in leaves were increased under low night temperature. And the activities of sucrose synthase （SS） and sucrose phosphate synthase （SPS） in leaves were decreased. [ Conclusion] Lead to carbohydrate accumulation in leaves under low night temperature, the photosynthesis feedback inhibition effect has been apparent.