外源6-BA对高温胁迫下甜椒幼苗叶绿素荧光参数和抗氧化酶活性的影响  

Effects of exogenous 6-BA on chlorophyll fluorescence parameters and antioxidant enzyme activities of sweet pepper seedlings under high temperature stress

作　　者：刘凯歌[1] 龚繁荣[1] 宋云鹏[1] 张丽丽[1] LIU Kaige;GONG Fanrong;SONG Yunpeng;ZHANG Lili(Horticultural Research Institute,Shanghai Academy of Agricultural Sciences,Shanghai Key Lab of Protected Horticultural Technology,Shanghai 201403,China)

机构地区：[1]上海市农业科学院设施园艺研究所,上海市设施园艺技术重点实验室,上海201403

出　　处：《上海农业学报》2020年第2期19-25,共7页Acta Agriculturae Shanghai

基　　金：上海市科学技术委员会科研计划项目(13391901100)。

摘　　要：为探明高温胁迫下外源6-BA对甜椒幼苗生理响应的调控机制,采用水培法研究了外源6-BA对不同高温处理时间下甜椒幼苗生长、叶绿素含量、叶绿素荧光参数、活性氧代谢和抗氧化酶活性以及MDA含量和相对电导率的影响.结果表明:(1)高温胁迫严重抑制了甜椒幼苗的生长,喷施外源6-BA可显著缓解高温带来的伤害,促进植株生长.(2)高温处理下,甜椒叶片叶绿素a、叶绿素b以及总叶绿素含量大幅下降,与之相比,S3处理组(高温条件下喷施10μmol/L 6-BA)分别上升了103.3%、106.9%和104.2%.(3)高温胁迫下,叶绿素荧光参数Fv/Fm、Yield、ψPSII显著降低,NPQ显著升高,喷施6-BA后,各项指标得到缓解并趋于常温水平.(4)抗氧化酶在高温条件下表现不同,但施加外源6-BA后,各抗氧化酶活性均表现出大幅增加的趋势.另外,喷施6-BA显著降低了甜椒幼苗叶片的O2^-·产生速率、MDA含量以及相对电导率.以上结果说明:6-BA在高温胁迫下促进了甜椒幼苗叶绿素的合成,缓解了高温导致的叶绿素含量降低,维持了正常的光合作用和甜椒幼苗的正常生长.6-BA在光能的吸收、转换、传递上起到了促进作用,从而使植物对光能的利用效率显著提升.6-BA增强了体内抗氧化酶活性以减轻膜脂过氧化作用,进而降低了O2-·的产生速率及MDA的积累.In order to explore the regulatory mechanism of exogenous 6-BA on the physiological response of sweet pepper seedlings under high temperature stress,the effects of exogenous 6-BA on the growth,chlorophyll content,chlorophyll fluorescence parameters,active oxygen metabolism,antioxidant enzyme activity,MDA content and relative electric conductivity of sweet pepper seedlings under different high temperature treatment time were studied by hydroponics.The results showed that:(1)high temperature stress seriously inhibited the growth of sweet pepper seedlings,exogenous 6-BA could significantly alleviate the damage caused by high temperature and promote the growth of plants.(2)Under high temperature treatment,the content of chlorophyll a,chlorophyll b and total chlorophyll in the leaves of sweet pepper decreased significantly,compared with S2 treatment,those of S3 treatment group(spraying 10μmol/L 6-BA at high temperature)increased 103.3%,106.9%and 104.2%respectively.(3)Under high temperature stress,chlorophyll fluorescence parameters Fv/Fm,Yield,φPSII decreased significantly,NPQ increased significantly.After spraying 6-BA,all indicators were relieved and tended to the level of normal temperature.(4)The activities of antioxidant enzymes were different under high temperature,but the activities of antioxidant enzymes increased significantly after exogenous 6-BA was applied.In addition,exogenous 6-BA significantly reduced the O2^-·production rate,MDA content and relative electric conductivity of sweet pepper seedling leaves.The above results indicated that 6-BA promoted the synthesis of chlorophyll,alleviated the decrease of chlorophyll content caused by high temperature,and maintained the normal photosynthesis and growth of sweet pepper seedlings.6-BA played an important role in the absorption,conversion and transmission of light energy,so that the utilization efficiency of light energy in plants was improved significantly.6-BA enhanced the activities of antioxidant enzymes in vivo to reduce membrane lipid peroxidation,

关 键 词：甜椒 6-BA 高温胁迫 叶绿素荧光参数 抗氧化酶活性 

分 类 号：S641.3[农业科学—蔬菜学]