两种基因型茶树新梢形态及叶片超微结构差异对其吸收累积稀土镧的影响  

Shoot morphology and leaf ultrastructure of two tea genotypes and their effects on rare earth lanthanum adsorption

作　　者：薛志慧[1,2,3,4] 王炫臻 赵静怡 柯子星 孙威江 XUE Zhihui;WANG Xuanzhen;ZHAO Jingyi;KO Tzuhsing;SUN Weijiang(College of Horticulture,Fujian Agriculture and Forestry University,Fuzhou 350002,China;Anxi College of Tea Science,Fujian Agriculture and Forestry University,Fuzhou 350002,China;Tea Industry Technology Development Base of Fujian Province,Fuzhou 350002,China;Tea Industry Engineering Technology Research Center of Fujian Province,Fuzhou 350002,China)

机构地区：[1]福建农林大学园艺学院,福州350002 [2]福建农林大学安溪茶学院,福州350002 [3]福建省茶产业工程技术研究中心,福州350002 [4]福建茶产业技术开发基地,福州350002

出　　处：《应用与环境生物学报》2020年第4期886-893,共8页Chinese Journal of Applied and Environmental Biology

基　　金：福建省自然科学基金项目(2016J01696);福建农林大学科技创新专项(CXZX2016003);安溪茶学院青年基金项目(ACKY2015003,ACKY2016005)资助。

摘　　要：不同基因型茶树品种对稀土的积累有显著性差异,但产生差异的生理机制仍不清楚.采用室内营养液培养法,对比研究稀土高/低积累基因型茶树品种铁观音和水仙在不同浓度稀土镧溶液(0.08、0.4和1.2 mmol/L)处理下的镧吸收量、生长发育以及叶片细胞超微结构的变化反应.结果显示,随着镧浓度的升高,不同叶位镧吸收量呈现出先降低后升高的规律,1.2 mmol/L镧浓度下,水仙品种不同叶位叶片镧积累量是铁观音的0.3-1.7倍.低浓度稀土镧处理下,两个品种茶树生长旺盛,新梢多为正常成熟新梢;高浓度处理下植株矮小,叶色黄绿,失去光泽,新梢生长和发育迟缓.扫描电镜观察发现低浓度稀土镧处理下细胞变化与对照相比差异不大,高浓度处理下叶片细胞褶皱明显,气孔周围蜡质增多.两个品种相比,铁观音较水仙蜡质覆盖量少,气孔密度大,受害程度较小,铁观音表现出较强的耐受性.透射电镜观察发现,高浓度稀土镧处理下两个茶树品种叶片细胞器受损,细胞质组分流失,水仙较铁观音受害程度严重.本研究表明水仙品种更容易受到稀土镧的毒害作用,铁观音表现出较强的耐性;不同茶树品种对稀土的生理反应差异结果可为茶树稀土低积累品种的筛选提供研究基础.(图7表1参27)The accumulation of rare-earth elements differs between different genotypes of tea trees,but the effects of rare earth element accumulation on the physiological mechanisms of tea trees are unclear.In this study,two tea tree varieties(Shuixian and Tieguanyin)were investigated for lanthanum(La)adsorption,growth conditions,and changes in the leaf cell ultrastructure under various La concentrations(0.08,0.4,and 1.2 mmol/L)in an indoor nutrient fluid culture system.The results showed that increased La concentrations were associated with initially lower La absorption,which then increased at different leaf positions.Under a La concentration of 1.2 mmol/L,the La accumulation at different leaf positions in Shuixian was 0.3-1.7 fold higher than in Tieguanyin.Under low La concentrations,growth was vigorous,and the new shoots were mature and healthy in both tea tree varieties.At high La concentrations,the plants were shorter,yellowish-green in color with tarnish,and the growth development of the new shoots were delayed.Scanning electron microscopy showed no significant differences in the cell structure of the control and low La concentration samples,whereas cell wrinkles were observed and wax grew around the stomata of the higher La concentration plants.Tieguanyin had less wax coverage,larger stomatal density,and less damage,indicating stronger tolerance.Transmission electron microscopy showed that the leaf organelles of two tea varieties were damaged,and the cytoplasmic components were lost in the high La concentration treatments,particularly for Shuixian.This study showed that the narcissus species are susceptible to La and Tieguanyin showed stronger tolerance.These results provide insight into the physiological reactions of different tea tree varieties to rare-earth elements and give useful information for screening low concentrations of rare-earth elements in tea trees.

关 键 词：稀土 镧 茶 基因型 超微结构 

分 类 号：S571.1[农业科学—茶叶生产加工]