细叶百合低温解除休眠过程中鳞茎内糖分及相关酶的研究

通过低温处理打破细叶百合鳞茎休眠,探讨细叶百合鳞茎解除休眠过程中的糖类化合物及蔗糖、淀粉代谢酶的变化规律。结果表明,鳞茎休眠解除过程中伴随着旺盛的糖类代谢活动,淀粉含量下降,淀粉酶活性升高。内层鳞片在冷藏60d时可溶性糖含量达到峰值,贮藏前期,蔗糖含量,蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性上升,SPS和SS协同控制蔗糖代谢及转运。冷藏条件下鳞片及顶芽内淀粉向可溶性糖方向代谢过程中促进了腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)活性的增加。各种淀粉代谢相关酶在鳞茎冷藏不同时期和不同部位的作用规律不同。鳞茎各个部位总可溶性糖含量与蔗糖、葡萄糖含量及淀粉磷酸化酶(SP)、SS、α-及β-淀粉酶活性都存在显著或极显著的正相关性。糖类代谢成为鳞茎休眠解除的物质基础。

Changes in carbohydrate status and related enzymes of Lilium pumilum bulbs during breaking dormancy under refrigerated conditions

The changes in carbohydrate levels and related enzyme activities during breaking dormancy under low temperature were studied in Lilium pumilum .Sugar metabolic activity was strong during breaking dormancy and the starch content of bulbs decreased,while amylase activity remained high.The concentration of soluble sugars peaked at 60 d of storage.In the early phase of storage,the sucrose content,and the activities of su-crose synthase (SS)and sucrose phosphate synthase were rising,synergistically controlling sucrose metabolism and transport.Under refrigeration the metabolism of starch to soluble sugar promoted an increase in AGPase activity.The functions and changes of enzymes involved in starch metabolism in different parts of the bulb were different.There were significantly or very significantly positive correlations of total soluble sugar content with the contents of sucrose and glucose,and the activities of starch phosphorylase,SS,and alpha and beta amylases in different parts of bulbs.Sugar metabolism was the primary metabolic activity for breaking dorman-cy of bulbs.