低温胁迫下烤烟幼苗叶片光合作用和抗氧化能力基因差异表达谱  

Expression profiling of genes related to photosynthesis and antioxidant capacity in flue-cured tobacco seedlings subjected to chilling stress

作　　者：崔翠[1] 王利鹃 周清元[1] 谭尊飞[1] 曲存民[1] 张正圣[1] 

机构地区：[1]西南大学,农学与生物科技学院,重庆400715

出　　处：《生态学报》2014年第21期6076-6089,共14页Acta Ecologica Sinica

基　　金：高等学校学科创新引智计划(B12006);重庆市自然科学基金项目(cst2011jj A80023);西南大学博士启动基金(SWU112074);中央高校基本科研业务费专项(2362014xk09;XDJK2014C150)

摘　　要：对低温(5—7℃)胁迫下烤烟"K326"幼苗叶片光合指标、膜氧化水平及其抗氧化指标进行测定,并利用数字化基因表达谱技术进行基因差异表达分析。低温胁迫后烤烟幼苗叶绿素含量、光合能力显著下降,脯氨酸含量、丙二醛含量上升,超氧化物歧化酶活性、过氧化氢酶活性、抗坏血酸含量和谷胱甘肽含量均显著上升。低温胁迫后有2357个基因发生了显著差异表达,其中1673个基因表达上调、684个基因表达下调,其分子功能、细胞位置和主要代谢过程均涉及光系统、膜氧化系统和抗氧化系统。对涉及到的代谢过程进行分析,结果表明:光合天线蛋白调控基因表达量均显著下降、光合作用的主要调控基因表达量多数表现为显著下调、而与氧化能力相关的谷胱甘肽代谢差异表达基因大多数显著上调。基因差异表达谱分析结果和低温胁迫后叶片光合能力、抗氧化能力生理生态指标测定结果基本一致,为进一步研究低温胁迫对作物的生态影响和研究基因克隆与功能提供基础。Tobacco is an important economical leaf crop and complex model organism that is cultivated worldwide.Low temperature is the one of major factors causing abiotic damage to flue-cured seedlings;this damage can affect the growth and development of flue-cured tobacco seedlings and can decrease the yield and quality of flue-cured tobacco leaves.Currently,technologies for cultivating seedlings by using water and oxygen have been widely adopted in southern tobacco-cultivating regions.However,temperature is dependent on climate,which is difficult to control artificially.Low temperatures during the early spring season limit the culture of strong seedlings in southern tobacco-cultivation areas.The objective of this study was to analyze physiological and ecological adaptations of flue-cured tobacco seedlings by measuring parameters related to levels of photosynthetic,oxidant,and antioxidant factors in the cell membranes of leaves.We also used digital gene expression profiling technology to analyze the differential expression of genes in flue-cured tobacco seedlings after chilling stress.Seedlings of flue-cured tobacco strain K326 were used as experiment materials.Tobacco seedlings with 5—6 true leaves were divided in two groups.One group of flue-cured seedlings was placed in a light incubator at a low temperaturerange of 5 ℃（ night） to 7 ℃（ day） for 3 days as chilling stress treatment.Seedlings in the other（ control） group remained at the initial temperature and illumination conditions and grew at a normal temperature range of 23 ℃（ night） to25 ℃（ day）,with other similar conditions.After chilling stress for 3 days,total chlorophyll（ Chl）,chlorophyll a（ Chl a）,and chlorophyll b（ Chl b） contents decreased significantly by 2.88% —6.82%,and the net photosynthetic rate（ Pn）,stomatal conductance（ Gs）,and transpiration（ Tr） decreased significantly by 14.14% —68.50% compared with that of seedlings grown under the favorable temperature.Intercellular CO2concentration（ Ci）

关 键 词：烤烟 低温胁迫 数字化基因表达谱 抗氧化能力 

分 类 号：S572[农业科学—烟草工业]