拔节期低温冻害对扬麦16光合特性及产量形成的影响  

Effect of low temperature at jointing stage on photosynthetic characteristics and yield in wheat cultivar Yangmai 16

作　　者：陈思思[1,2] 李春燕[1] 杨景[1] 徐雯[1] 朱新开[1] 郭文善[1] 封超年[1] 

机构地区：[1]扬州大学农学院/江苏省作物遗传生理重点实验室,江苏扬州225009 [2]启东市农业委员会,江苏启东226200

出　　处：《扬州大学学报（农业与生命科学版）》2014年第3期59-64,共6页Journal of Yangzhou University：Agricultural and Life Science Edition

基　　金：国家自然科学基金资助项目(31000683);江苏省高校自然科学基金资助项目(10KJB210007);江苏省科技支撑计划项目(BE2012467);江苏高校优势学科建设工程项目(20101105)

摘　　要：以扬麦16为试验材料,利用人工气候室模拟低温逆境,研究拔节期低温对扬麦16光合特性和产量形成的影响。结果表明:拔节期-2、-4℃低温胁迫48h,叶片叶绿素a、叶绿素b、叶绿素总量均呈下降趋势,叶绿素a/b比呈先下降后上升的趋势。低温胁迫下叶片净光合速率、气孔导度、蒸腾速率均随胁迫程度的加重而显著下降,胞间CO2浓度则先下降后上升,-2℃胁迫12h、-4℃胁迫6h引起光合作用的气孔限制、-2℃胁迫12h以上、-4℃胁迫6h以上引起光合作用的非气孔限制以及叶绿素含量显著下降是导致光合速率下降的主要原因。产量随着胁迫程度的加重减产越重,-2、-4℃处理胁迫48h,产量较对照分别下降71.08%和80.15%,穗数和每穗粒数显著下降是冻害减产的主要原因。Photosynthetic characteristics and yield changes of wheat （cv. Yangmail6） under low temperature treat- ments （ 2, -4 ℃） at jointing stage were studied by means of artificial temperature-controlled phytotron. The contents of chlorophyll, chlorophyll a （chl a）, and chlorophyll b （chl b） in leaves decreased significantly under lower temperatures and longer stress. The ratio of chlorophyll a to chlorophyll b decreased at the preliminary stage, and then increased. Un- der low temperature stress, net photosynthesis rate （Pn）, stomatal conductance （G）, transpiration rate （Ti） decreased, whereas intercelecullar COz concentration （C5） decreased firstly and then increased significantly. Under the stress of --2 ℃ lasting for 12 h and --4 ℃ lasting for 6 h, the decrease in photosynthetic rate was mainly caused by stomatal fac- tors. Under the stress of --2 ℃ lasting for more than 12 h and --4 ℃ lasting for more than 6 h, the decrease in photo- synthetic rate was primarily caused by non-stomatal factors. Therefore, stomatal effects, non-stomatal effects and chloro- phyll content reduction mainly caused the decrease in net photosynthetic rate of wheat plants under cold stress. The lon- ger and lower temperature was, the more yield declined. The yield of the treatments of --2 ℃ and --4 ℃ lasting for 48 h were significantly lower than that of the control, which decreased by 71.08 % and 80.15 % respectively. The number of spikes and grains per ear reduction were the main reasons of yield decrease under low temperature stress at jointing stage.

关 键 词：小麦 低温 光合特性 产量 

分 类 号：S512[农业科学—作物学]