黄瓜幼苗Rubisco与Rubisco活化酶对光强的响应  

Response of Rubisco and Rubisco Activase in Cucumber Seedlings to Light Intensity

作　　者：姜振升[1] 刘培培[1] 王美玲[1] 毕焕改[1] 艾希珍[1] 

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

出　　处：《西北农业学报》2011年第9期95-99,共5页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：国家自然科学基金(30972032);博士点基金(20070434002)

摘　　要：以津优3号幼苗为试材,研究弱光(LL:100μmol.m-2.s-1)、亚弱光(SL:300μmol.m-2.s-1)下黄瓜幼苗光合速率(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变化。结果表明,11 d弱光处理后,黄瓜幼苗叶片的Pn、Rubisco初始活性、总活性及RCA活性均显著降低,亚弱光处理的Pn也明显降低,但其Rubisco初始活性和总活性与CK差异不显著。弱光和亚弱光处理的rbcS相对表达量有所降低,而rbcL和CsRCA相对表达量明显增加。说明弱光下Rubisco和RCA活性降低是引起Pn降低的重要原因之一,但当光强达到300μmol.m-2.s-1时,Rubisco和RCA活性与Pn相关性不明显。较长时间的弱光处理后,Pn的降低与rbcS相对表达量减小有关,而rbcL和CsRCA的表达量增加可在一定程度上弥补Rubisco和RCA活性降低引起的光合速率下降。Changes of photosynthetic rate（Pn）,activities and gene expression of Ribulose 1,5-bisphosphate carboxylase/oxygenase（Rubisco） and Rubisco activase（RCA） in Jinyou 3 cucumber seedlings under low light intensity（LL： 100 μmol·m-2·s-1） and suboptimal light intensity（300 μmol·m-2·s-1） were investigated.The results showed that low light intensity led to remarkable decrease in Pn and activities of Rubisco and RCA.Suboptimal light intensity also caused to a significant decrease in Pn,but no notable differences in Rubisco activity,compared with control.The treatments of LL and SL showed a decline in rbcS expression,whereas increase in expression of rbcL and CsRCA.These data suggested that the decrease in activities of Rubisco and RCA under low light intensity is one of the important reasons which result in decrease in Pn.However,there are not significant correlation between Pn and activities of Rubisco and RCA,when photo flux density（PFD） is higher than 300 μmol·m-2·s-1.Low Pn under weak light condition is related to the decline of rbcS expression.Increase of rbcL and CsRCA expression may compensate the decrease of Pn resulted by the decline of Rubisco and RCA activities under low light intensity.

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

分 类 号：S642.2[农业科学—蔬菜学]