茶树越冬芽在休眠与萌发时期的物质交流变化及其分子调控  

Molecular Regulation and Substance Exchange Dynamics at Dormancy and Budbreak Stages in Overwintering Buds of Tea Plant

作　　者：唐湖 郝心愿[2] 王璐[2] 肖斌[1] 王新超[2] 杨亚军[1,2] 

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100 [2]中国农业科学院茶叶研究所/国家茶树改良中心/农业部茶树生物学与资源利用重点实验室,浙江杭州310008

出　　处：《作物学报》2017年第5期669-677,共9页Acta Agronomica Sinica

基　　金：国家自然科学基金项目(31370690);国家现代农业产业技术体系建设专项(CARS-23);中国农业科学院农业科技创新工程(CAAS-ASTIP-2014-TRICAAS)资助

摘　　要：为揭示不同萌发物候型茶树的休眠机制,以特早生茶树品种龙井43和中生茶树品种碧云为材料,利用钙黄素处理茶树茎段,检测越冬芽在休眠与萌发时期与其他器官的物质交流情况。利用同源比对鉴定胼胝质水解相关基因,并分析其序列特征及在冬季不同时期的表达模式。结果表明,越冬芽在茶树生长阶段和休眠阶段都存在着与着生茎段和母叶间的物质交流;从茶树越冬芽休眠形成到解除的不同时期,其物质交流存在"强-弱-强"的变化规律,但龙井43的与碧云相比存在较短的物质交流减弱时期;两种茶树的物质交流变化模式与鉴定到的茶树胼胝质水解正向调控相关基因CsGLU1的表达模式密切相关;启动子序列分析进一步证实CsGLU1启动子区有多个与激素信号以及低温和休眠响应相关转录因子结合的保守序列。茶树越冬芽在休眠和非休眠状态下都存在与茎和母叶之间的物质交流,且物质交流强弱与茶树越冬芽休眠状态改变密切相关。CsGLU1可能是参与胼胝质水解调控,改变茶树越冬芽物质交流水平,进而影响茶树休眠状态的关键基因。这对明确茶树越冬芽休眠状态变化和深入揭示不同萌发物候型茶树休眠机理有重要意义。Early-sprouting cultivar Longjing 43 and late-sprouting cultivar Biyun were employed in this study to disclose the dormancy mechanism in tea plant with different sprouting phenophases. The levels of substance exchange were monitored by detecting the fluorescence signal in calcein treated overwintering buds. The glucanase related genes were identified by sequence homology analysis. Their characteristics and expression patterns during different time of winter were further analyzed. The substance exchanges were detected either in stem-bud unit or mother leaf-stem unit. From the initial formation to release in dormancy, the substance exchange in overwintering buds showed strong-weak-strong variation patterns in both cultivars, however, the duration of weak exchange stage was much shorter in Longjing 43 than in Biyun. Moreover, there was a close correlation between substance exchange variation pattern and the expression pattern of CsGLU1, a gene identified in tea plant with positive callose hydrolyzation activity. On the basis of promoter sequence analysis, plenty of transcription factor binding sequences related to hormone signaling, cold stimulation and dormancy regulation were found in CsGLU1 promoter region, which validates its putative functions in dormancy regulation. In conclusion, overwintering buds of tea plant have substance exchange with stem and mother leaf both in dormancy and non-dormancy status, furthermore, the variation of substance exchange level was consistent to the changes of dormancy status. CsGLU1 is a callose hydrolyzation related gene, which is supposed to be a key gene regulating tea plant dormancy transition through affecting the substance exchange in overwintering buds. The study provides meaningful results for understanding the changes of dormancy statuses in overwintering buds and deeply exploring the regulation mechanism in tea plant with different sprouting phenophase.

关 键 词：茶树 越冬芽休眠 物质交流 钙黄素 

分 类 号：S571.1[农业科学—茶叶生产加工]