低温弱光对黄瓜幼苗Rubisco与Rubisco活化酶的影响  

Responses of Rubisco and Rubisco activase in cucumber seedlings to low temperature and weak light.

作　　者：姜振升[1] 孙晓琦[1] 艾希珍[1] 王美玲[1] 毕焕改[1] 王洪涛 

机构地区：[1]山东农业大学园艺科学与工程学院作物生物学国家重点实验室/园艺作物生物学农业部重点开放实验室,山东泰安271018 [2]山东省枣庄市农业示范园,山东枣庄277300

出　　处：《应用生态学报》2010年第8期2045-2050,共6页Chinese Journal of Applied Ecology

基　　金：教育部博士点基金项目(20070434002);国家自然科学基金项目(30972032);国家重点基础研究发展计划项目(2009CB119000);国家"十一五"科技支撑计划项目(2006BAD07B04-9);现代农业产业技术体系建设专项资金项目资助

摘　　要：以‘津优3号’黄瓜幼苗为试材,研究弱光(100μmol.m-2.s-1)下适温(WL:25℃/18℃)、亚适温(ST+WL:18℃/12℃)和低温(LT+WL:10℃/5℃)对黄瓜幼苗光合速率(Pn)、核酮糖-1,5-二磷酸羧化/加氧酶(Rubisco)、Rubisco活化酶(RCA)活性及其基因表达量的影响.结果表明:与对照(25℃/18℃,400μmol.m-2.s-1)相比,WL、ST+WL和LT+WL处理的单株叶面积和干物质量均明显减小.处理初期,Pn、Rubisco活性及其大亚基基因(rbcL)、小亚基基因(rbcS)表达、RCA活性与基因(CsRCA)表达量大幅度降低,5～7 d后,WL处理趋于平稳,ST+WL处理缓慢回升,而LT+WL处理持续下降,表明黄瓜光合机构对适温弱光和亚适温弱光环境有逐步适应机制.Rubisco和RCA活性及其基因表达对低温弱光的响应与Pn基本一致,表明低温弱光下RCA和Rubisco活性及其基因表达量下降是黄瓜幼苗Pn降低的重要原因.Using ＇Jinyou 3＇ cucumber seedlings as test materials,this paper studied their photosynthetic rate（Pn）,Ribulose 1,5-bisphosphate carboxylase/oxygenase（Rubisco） and Rubisco activase（RCA） activities,and gene expression of Rubisco and RCA under optimal temperature and weak light（WL： 25 ℃/18 ℃,100 μmol·m-2·s-1）,suboptimal temperature and weak light（ST＋WL： 18 ℃/12 ℃,100 μmol·m-2·s-1）,and low temperature and weak light（LT＋WL： 10 ℃/5 ℃,100 μmol·m-2·s-1）.Comparing with the control（25 ℃/18 ℃,400 μmol·m-2·s-1）,treatments WL,ST＋WL,and LT＋WL all led to a remarkable decrease in leaf area and dry matter mass.At initial stage,the Pn,Rubisco activity,rbcL and rbcS expression,RCA activity,and CsRCA expression in the three treatments declined by a big margin;5-7 days later,these parameters tended to be less changed in treatment WL,ascended slowly in treatment ST＋WL,and decreased continuously in treatment LT＋WL.These results suggested that the photosynthetic apparatus of test cucumber seedlings could gradually adapt to weak light or suboptimal temperature and weak light.The Rubisco and RCA activities and the gene expression of Rubisco and RCA showed the similar responses to low temperature and weak light as the Pn,suggesting that the decline in Rubisco and RCA activities and gene expression in cucumber seedlings under low temperature and weak light could be the important reason leading to the decrease of Pn.

关 键 词：核酮糖-1 5-二磷酸羧化/加氧酶(Rubisco) Rubisco活化酶(RCA) 基因表达 低温弱光 亚适温弱光 黄瓜 

分 类 号：S642.2[农业科学—蔬菜学]