板栗雏梢分化期内源激素的动态变化特征

Changes of Endogenous Hormones during the Younger Shoot Differentiation of Chestnut

以3个品种板栗上部芽为材料,采用石蜡切片法确定板栗雏梢分化进程,再运用高效液相色谱(HPLC)对雏梢分化期内源激素含量进行分析,探讨板栗内源激素与花芽分化的关系。结果表明:板栗雏梢分化进程可划分为冬前花序原基分化期、休眠期、冬后花序原基分化期、花簇苞片原基分化期和花簇原基分化期5个时期。在板栗整个雏梢分化过程中,各品种芽内源ZT含量总体呈"M"形双峰曲线变化,分别在11月中旬和翌年1月中旬出现峰值;芽内源GA3含量也总体呈双峰曲线变化,分别在冬前花序原基分化期(10月中旬)和冬后花序原基分化期(翌年2月中旬)达到峰值;内源ABA含量在冬前花序原基分化期达到最大值,之后呈逐渐下降,于1月中旬降到一个较低的水平并一直维持至花簇原基分化期(3月中旬)。内源激素GA3/ZT值从9月中旬开始持续下降,于冬前花序原基分化过后下降到低水平状态并保持至花簇原基分化期。可见,在整个板栗雏梢分化过程中,较高浓度GA3有利于花序原基的分化,低水平的ABA有利于休眠期的解除和冬后花序原基的分化;内源激素GA3和ZT间的平衡关系在板栗雏梢分化的过程中起着重要的调控作用。

By high performance liquid chromatography,the changes of endogenous hormone contents in the upper buds of 3 chestnut cultivars were studied during the younger shoot differentiation stage which was defined through paraffin cut method.The results showed that the younger shoot differentiation progress could be divided into 5 stages：pre-winter inflorescence primordium differentiation stage,dormancy stage,post-winter inflorescence primordium differentiation stage,flower clusters bract primordium differentiation stage and flower cluster primordium differentiation stage.The changes of ZT content shown a curve just like a ＇M＇,the two peaks appeared in mid-November and mid-January,respectively.In the progress of the younger shoot differentiation,the GA3 content had a curve with two peaks and reached the peak at pre-winter inflorescence primordium differentiation stage（mid-October） and post-winter inflorescence primordium differentiation stage（mid-February next year）,respectively.ABA content reached maximum at pre-winter inflorescence primordium differentiation stage（mid-October） and then decreased slowly.The content of ABA decreased to a stable low level in mid-January and maintained this level to flower cluster primordium differentiation stage（mid-March next year）.The value of GA3/ZT decreased slowly from mid-September and reached a lower level after pre-winter inflorescence primordium differentiation stage,then maintained this lower level to flower cluster primordium differentiation stage（mid-March next year）.In the younger shoot differentiation stage of chestnut,the higher GA3 content will be beneficial to the differentiation of inflorescence primordium.The lower ABA content would be beneficial to the promotion of dormancy breaking and the differentiation of the post-winter inflorescence primordium.The balance of endogenous hormones GA3 and ZT also played an important role in regulating and controlling the younger shoot differentiation of chestnut.