低温对缺钼冬小麦幼苗生长的影响Ⅰ.对糖代谢的影响

Effect of molybdenum on growth of winter wheat seedlings induced by low temperature

对三叶一心的缺钼冬小麦进行 2 4h低温处理 (- 5℃～ 0℃ )后 ,冬小麦幼苗出现缺钼症状 ,并迅速波及整个植株 ,下部叶片尤为严重。缺钼及低温对幼苗地上部、根干重无明显影响 ;但经低温处理的冬小麦幼苗叶片色素含量下降 ,以叶绿素a +b减少最为明显 ;缺钼植株上部叶片在低温处理到 2 4h时 ,K+ 渗漏速率出现最大值 ,下部叶片在 9h时即达到高峰。常温下 ,供钼能提高冬小麦功能叶 (倒二叶 )可溶性总糖、蔗糖含量 ,同时使倒三叶中可溶性总糖、蔗糖含量也保持在较高水平 ;低温条件下 ,供钼植株倒三叶、功能叶可溶性总糖、蔗糖含量明显降低 ,缺钼植株功能叶糖含量下降 。

Low temprature(LT) has been underway for 24h when winter wheat seedlings are 28 days old. Results as followed: symptom of Mo deficiency appears quickly in whole plant after induced by LT; Mo and LT have no effects on DW of shoot and root; Chlorophyll content in different parts of winter wheat seedlings is dropped induced by LT, especially Chla+b; K + leakage rate of upper leaves maxims when time of LT is 24h, while that of lower leaves is 9h; Under NT conditions, total soluble sugar and sucrose of functional and primary leaves in Mo applied keep at a high level, under LT conditions, total soluble sugar and sucrose of functional and primary leaves in Mo applied decrease, those of functional leaves in Mo deficient drop too, but those of primary leaves raise.