低温和赤霉素对百合鳞茎休眠解除的影响

Effects of Temperature and GA_3 on the Breaking Dormancy in Lily Bulbs

以百合品种＂西伯利亚＂为材料,研究了低温和赤霉素（GA3）处理对百合鳞茎休眠解除过程中形态和碳水化合物含量的影响,以及不同温度条件下鳞茎不同部位内源GA3含量的变化。结果表明：低温（5℃）和0.15g·L-1GA3处理35d时芽长与鳞茎高比值为67.954%,芽生长点位于鳞茎直立高度约2/3处,解除休眠所需天数最少;鳞茎在0~14d时淀粉降解最快,第35天时可溶性总糖和还原糖含量最高。低温处理的内层鳞片和芽内源GA3含量变化显著,且温度越低,变化越明显。低温条件下内层鳞片和芽的内源GA3含量较高,上升趋势最为明显;而外层鳞片和根的GA3含量水平较低,变化趋势较小。可见,顶芽和内层鳞片可能为整个鳞茎休眠解除活动的中心。

To investigate an effective way to break dormancy in Lily bulbs,Siberian Lily bulbs were used to study the effects of low temperature and GA3 on the morphological and physiological changes,the change of endogenous GA3 in different temperature and different parts of lily bulbs.The results showed that,the ratio of bud length and total height of bulbs reached 67.954%,the bud growth point located at the 2/3 vertical height of bulb,and the time spent on dormancy releasing was minimum under the treatment of low temperature（5℃）and GA3（0.15 g爛L-1）for 35 d.Under the condition of low temperature（5℃）,the starch degradation rate was fastest in bulbs with the treatment of 0.15 g爛L-1 GA3 in 0-14 d,moreover,the soluble sugar content and reducing sugar content reached the maximal value at the 35 th d.The endogenous GA3 content was changed noticeably in inner scales and buds under low temperature condition,and the changes was more visible with the decreasing of temperature.Consequently,low temperature and GA3 treated together have significant effects on dormancy breaking in bulb of Siberia Lily,the optimum concentration of GA3 was0.15 g爛L-1,the optimum temperature was 5℃.The endogenous GA3 content was higher with low temperature treatment in inner scales and buds,and had the most evident escalating trend;however,the endogenous GA3 content was lower in outer scales and roots,and had a less change trend.It will be seen from this that,the kernel of dormancy breaking in the whole bulb might be the terminal bud and inner scales.