【作者】 梁芳； 郑成淑； 孙宪芝； 王文莉； 孙霞；

【Author】 LIANG Fang ZHENG Cheng-shu SUN Xian-zhi WANG Wen-li SUN Xia (State Key Laboratory of Crop Biology,College of Horticulture Science and Engineering, Shandong Agricultural University,Tai’an 271018)

【机构】 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；

【摘要】 以切花菊品种‘神马’为试材,在偏低温弱光(16℃/12℃,PFD100μmol·m^-2·s^-1)、临界低温弱光(12℃/8℃,PFD60μmol·m^-2·s^-1)下分别胁迫11 d,然后转入CK(22℃/18℃,PFD450μmol·m^-2·s^-1)恢复11d,研究不同低温弱光强度及恢复对菊花光合作用和叶绿素荧光参数的影响。结果表明低温弱光导致菊花叶片的净光合速率（Pn）与气孔限制值（Ls）下降,而胞间浓度CO₂浓度（Ci）上升。引起Pn下降的主要原因是非气孔因素;偏低温弱光胁迫对菊花叶片的暗适应下最大光化学效率（Fv/Fm）和初始荧光（Fo）并无影响,光适应下最大光化学效率（Fv′/Fm′）处理前期略有下降,后期则有所回升,而临界低温弱光处理的Fo明显升高,Fv/Fm和Fv′/Fm′显著降低。PSⅡ光合电子传递量子效率（ΦPSⅡ）、光化学猝灭系数（qP）和电子传递速率（ETR）均随着低温弱光胁迫程度的增加和时间的延长而降低;偏低温弱光处理植株在解除胁迫后能迅速恢复到对照水平,而临界低温弱光处理植株回升速度较慢;同时,吸收光强分配于光化学反应的部分（Prate）减少,而天线热耗散（Drate）和反应中心的能量耗散（Ex）比例上升,但天线热耗散为主要的过剩光能分配途径。从整体看,临界低温弱光使上述参数变化的程度要比偏低温弱光明显。更多还原

【Abstract】 Cut flower chrysanthemum（Dendranthema grandiflora’Jinba’） plants were selected as material in this study to research the effects of the combination of lower temperature and poor light(16℃/ 12℃,PFD100μmol·m^-2·s^-1),critical temperature and poorlight(12℃/8℃,PFD60μnol·m^-2·s^-1) stress for 11 days and then transferred to CK(22℃/18℃, PFD450μmol·m^-2·s^-1 )for 11 days to study the changes on photosynthesis and chlorophyll fluorescence parameters Characteristic in chrysanthemum leaves.The results showed that net photosynthetic rate（Pn） and stomatal limitation（Ls） value decreased, however intercellular CO₂ concentration（Ci） decreased.The cause of reduction of Pn in chrysanthemum under low temperature and poor light stress might be mainly non - stomata limitation.The combination of poor light and lower temperature stress did not affect maximal photochemical efficiency of PSⅡin the dark（Fv/ Fm） and initial fluorescence（Fo）,and led to a little decrease during the early period of stress and recovered slowly during the later period of stress in maximal photochemical efficiency of PSⅡin the light（Fv’/Fm’）;but Fo increased and Fv/Fm and Fv’/Fm’ decreased evidently under the combination of critical temperature and poor light;ΦPSⅡ,qP and Fv’/Fm’ decreased with degree increasing and time prolonging of low temperature and poor light and arose to a value similar to control for the combination of poor light and low temperature stress,but recovered slowly for the combination of critical temperature and poor light stress after relieving the stress;At the same time,Prate decreased,but Drate and Ex increased under low temperature and poor light.Drate was the main way of superfluous light allocation.In all,the changes of the above parameters were smaller significantly under the critical temperature and poor light stress than the lower temperature and poor light.更多还原