低温胁迫对澳洲茶树组培苗生理特性的影响  

Effects of low temperature stress on physiological characteristics of Melaleuca alternifolia tissue culture seedlings

作　　者：张晓宁[1,2] 杨红 张烨[1,2] 陈博雯 肖玉菲[1,2] 覃子海 刘海龙[1,2] ZHANG Xiaoning;YANG Hong;ZHANG Ye;CHEN Bowen;XIAO Yufei;QIN Zihai;LIU Hailong(Guangxi Forestry Research Institute,Nanning 530002,China;Guangxi Key Laboratory of Cultivation and Utilization of Characteristic Economic Forests,Nanning 530002,China;Kunming Institute of Botany,Chinese Academy of Sciences,Kunming 650201,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]广西壮族自治区林业科学研究院,南宁530002 [2]广西特色经济林培育与利用重点实验室,南宁530002 [3]中国科学院昆明植物所,昆明650201 [4]中国科学院大学,北京100049

出　　处：《广西植物》2021年第9期1534-1541,共8页Guihaia

基　　金：广西自然科学基金(2016GXNSFBA380224);广西科技计划项目(桂科AD18281083,桂科AB18221058);南宁市青秀区科技计划项目(2018019,2019016);广西中药质量标准研究重点实验室开放课题(桂中重开202002);广西林科院基本科研业务费专项(林科201812号)。

摘　　要：为探讨澳洲茶树组培苗耐受低温的能力及对低温胁迫的响应机制,该文测定了3月龄澳洲茶树组培苗低温处理过程及恢复培养后叶片叶绿素(Chl)、丙二醛(MDA)、抗氧化物酶(SOD,POD,CAT)、抗坏血酸(AsA)、谷胱甘肽(GSH)、可溶性糖(SS)、可溶性蛋白(SP)、游离脯氨酸(Pro)的变化。结果表明:(1)-5℃胁迫24 h,保护酶及抗氧化物含量均显著下降,MDA含量显著上升。(2)0℃下,AsA和GSH先降后升,POD和CAT相反,SOD持续升高;胁迫48 h后保护酶活性显著升高,抗氧化剂含量显著降低。(3)10℃下,SOD活性先降后升;胁迫48 h后,渗透调节物质含量均显著升高。因此,3月龄澳洲茶树组培苗在-5℃受到致死冻害,幼苗能通过启动抗氧化系统及快速积累渗透调节物质响应0℃以上低温胁迫,但对10℃和0℃两种低温胁迫的应答机制却存在一定的差异。该研究结果将有助于深入了解其对低温的耐受能力及生理响应机制,为合理引种及规模化种植提供理论依据。To explore the response and adaptive mechanisms of Melaleuca alternifolia tissue culture seedlings to cold stress,3-month-old tissue culture seedlings were exposed to low temperatures and then recovered at air temperature,the physiological indexes including chlorophyll(Chl),malondialdehyde(MDA),antioxidant enzymes(SOD,POD,CAT),ascorbic acid(AsA),glutathione(GSH),soluble sugar(SS),soluble protein(SP),free proline(Pro)were examined.The results were as follows:(1)The stress at-5℃for 24 h caused a significant decrease in the activities of antioxidant enzymes and the contents of antioxidants,but an increase in the content of MDA.(2)At 0℃,the activities of POD and CAT first rose and then descended,while the contents of AsA and GSH showed an opposite pattern;After 48 h of stress,the activities of protective enzymes significantly increased but the contents of antioxidants decreased.(3)At 10℃,the activity of SOD first elevated and then declined;All three osmotic regulators manifested a remarkable elevation after the 48 h of stress.Collectively,the 3-month-old tissue cultures seedlings of M.alternifolia could be lethally injured at-5℃,but they were able to survive the low temperature above 0℃by rapidly increasing protective enzyme activities and accumulating osmotic regulators.However,there was a certain difference in mechanisms underlying the response to low temperature stress at 10℃and 0℃.The results of this study will help to understand its cold resistance ability and physiological response mechanism,and provide the theoretical basis for rational introduction and large scales of planting.

关 键 词：澳洲茶树 低温胁迫 形态特征 抗氧化物酶 抗氧化剂 渗透调节物质 

分 类 号：Q945[生物学—植物学]