Mechanisms on inhibition of photosynthesis in Kandelia obovata due to extreme cold events under climate change  

作　　者：Chunfang Zheng Jianwu Tang Jinong Chen Weicheng Liu Jianbiao Qiu Xin Peng Yong Ye 

机构地区：[1]Zhejiang Mariculture Research Institute,Zhejiang Key Laboratory of Exploitation and Preservation of Coastal Bio-resource,Wenzhou 325005,Zhejiang,People’s Republic of China [2]Nanji Islands National Marine Nature Reserve Administration,Pingyang 325401,People’s Republic of China [3]Key Laboratory of the Ministry of Eduction for Coastal and Wetland Ecosystem,College of the Environment and Ecology,Xiamen University,Xiamen 361005,People’s Republic of China

出　　处：《Ecological Processes》2016年第1期250-260,共11页生态过程（英文）

基　　金：funded by the projects of Special Funding for Research of National Oceanic Public Service Industry(201505028);Zhejiang Provincial Natural Science Foundation(LQ13C030002);Science and Technology Plan of Zhejiang Province(2012C12017-3,2013C25096,and 2014F50003);China and Israel Cooperation Project(2015);Wenzhou Municipal Science and Technology Plan Project(S20110007).

摘　　要：Introduction:Mangroves that grow at the latitudinal extremes of their distribution are susceptible to extreme cold events.Successive enhancement of low temperature stress(seLTS)is a typical characteristic of extreme cold events.Low temperature stress can inhibit mangrove photosynthesis,which often inhibits the growth and development of mangroves.However,the possible reasons for impairment to photosynthesis of mangroves due to extreme cold events remain unclear.Methods:Kandelia obovata seedlings in a growth chamber were exposed to 5℃/−2℃(day/night)for 36 h(−2℃ for 16 h)with 12 h light per day at 600μmol m^(−2) s^(−1) photosynthetic photon flux density(PPFD)(a low temperature stress,aLTS),then the plants were transferred to the control condition(15℃/10℃(day/night)and allowed to recover for 5 days(R1).The other seedlings were subjected to low temperature treatment with a day/night temperature of 5℃/−1℃ in a growth chamber for 24 h.Then these plants were transferred to 5℃/−2℃(day/night)under the same light and climate conditions for 36 h(two low temperature stresses,tLTS).Following the successive enhancement of low temperature treatment,these plants were returned to 15℃/10℃(day/night)for another 5-day recovery period(R2).Results:Results showed that aLTS treatment significantly reduced leaf net photosynthetic rate(P_(n))and stomatal conductance(G_(s)),while increased intercellular CO_(2) concentration(C_(i)).Photosynthetic activity of leaves quickly recovered after the plants were returned to control temperature for 5 days(R1).However,decreases in leaf Pn were more obvious under tLTS treatment than those under aLTS treatment.This reduced Pn might be attributed to stomatal and non-stomatal limitations.Moreover,non-stomatal limitation played a major role in reducing Pn during tLTS treatment,as proven by reduced ribulose 1,5-biphosphate carboxylase(RuBPCase)activity.This limitation also enhanced lipid peroxidation in chloroplasts,decreased sucrosemetabolizing enzymes and ratios of both

关 键 词：Kandelia obovata Low temperature Gas exchange Sucrose synthesis PEPTIDASE 

分 类 号：Q94[生物学—植物学]