红叶樱花不同采集时期外植体萌芽差异及其原因分析

Differences of Axillary Bud Germination in Vitro and Their Causal Analysis in Different Explant Harvesting Period of Prunus serrulata ‘Royal burgundy'

为了研究适宜红叶樱花腋芽萌发的外植体采集时期及其潜在的内源物质影响规律,分别在1—5月的每月中旬采集红叶樱花枝条,以枝条腋芽为外植体进行萌芽试验,同时测定各个时期外植体的可溶性糖、可溶性蛋白、内源激素含量,观察不同时期外植体内源物质含量的变化规律。结果表明:1—2月中旬红叶樱花腋芽处于休眠期,ABA、GA3含量与休眠分别呈正、负相关,IAA、可溶性糖和可溶性蛋白在冷胁迫下含量较高;2—3月中旬,ABA、IAA、可溶性蛋白含量开始反向变化,慢慢解除休眠;3月中旬解除休眠因子GA3和可溶性糖含量大幅增加,GA3/ABA比值大幅上升,红叶樱花腋芽组培萌发率较高但萌发后生长缓慢;4月中旬,ZA/IAA比值开始上升,此时期红叶樱花腋芽组培萌发率最高,表明GA3含量和GA3/ABA比值在指示红叶樱花休眠中具有重要作用,ZA含量和ZA/IAA比值在红叶樱花腋芽组培生产中具有重要指导作用。春季新萌枝条适宜作为红叶樱花组织培养的外植体,排除酚类物质引起的褐化影响,最适的采集时期是4月中旬。

In order to study the effects of explant harvesting period and its potential endogenous substance on the axillary bud germination of Prunus serrulata‘Royal burgundy’,the branches were collected in mid-month from January to May,and the buds on the branches were used as explants.The contents of soluble sugar,soluble protein and endogenous hormones in the explants were measured at different time points,and the changes of the contents of endogenous substances in the explants were observed.The results showed that the contents of ABA and GA3 were positively and negatively correlated with dormancy respectively,and the contents of IAA,soluble sugar and soluble protein were higher under cold stress.In the middle of February andMarch,the contents of ABA was positively correlated with dormancy,while IAA and soluble protein content began to reverse the change showing dormancy release.In mid-March dormancy release factor GA3,soluble sugar content and GA3/ABA ratio increased significantly,the germination rate of axillary bud in tissue culture was high but slowed down after germination.In the middle of April,ratio of ZA/IAA begin to increase,and axillary bud germination was the highest,indicating that the ratio of GA3 and GA3/ABA played an important role in the dormancy.ZA and ZA/IAA played an important guiding role in the propagation of Prunus serrulata‘Royal burgundy’.In the spring,the new shoots were suitable as explants for tissue culture of Prunus serrulata‘Royal burgundy’,eliminating the browning effect caused by phenolic substances,the optimum collection period was in mid-April.