草业科学2017，Vol.34Issue(5)：1024-1031,8.DOI:10.11829/j.issn.1001-0629.2016-0484
镉处理后两种景天的光合相关参数变化
Variation in photosynthesis related parameters in two kinds of Sedum after cadmium treatment
摘要
Abstract
Hyperaccumulator plants are recognized as promising phytoremediation candidates owing to their ability to accumulate substantial heavy metal ions without obvious signs of poisoning.Two ecotypes of Sedum alfredii (hyperaccumulating,HE and non-hyperaccumulating,NHE) were employed for hydroponic experi ments with a modified culture solution.The chlorophyll content,photosynthetic parameters,and chlorophyll fluorescence characteristics were analysed.The results indicated that the chlorophyll a (Chla) and chlorophyll b (Chlb) content of the HE plants significantly decreased (P＜0.05) by 46.91％ and 43.09％,respectively,compared with non-Cd treated samples after stress for 7 days,whereas the Chla and Chlb contents of NHE were significantly decreased by 50.9％ and 49.98％,respectively.Under the stress,the decrease in net photosynthetic rate (Pn) in HE was less than that in NHE.The Pn of HE was 31.97％ less than that of the control and 50.69％ less in NHE;both changes were statistically significant.The transpiration rate (Tr) of HE decreased by 50.58％ after stress for 4 days and then increased,whereas the Tr of NHE decreased by 60.47％ after stress for 1 day and then increased.The initial fluorescence (F0) of HE increased promptly and then decreased,whereas the F0 of NHE gradually increased during stress for 4 days.The maximum fluorescence (Fm) in HE was always higher than NHE.The actual photochemical efficiency (ΦPSⅡ),photochemical quenching coefficient (qP),and apparent photosynthetic electron transport rate (ETR) of HE firstly decreased and then increased,whereas the ΦPSⅡ and ETR of NHE were stable after a decrease.The non-photochemical quenching coefficient (NPQ) of HE gradually increased,whereas NPQ and qP tended to be stable.Thus,the response of the two ecotypes of Sedum to cadmium treatment was completely different.This study also investigated the physiological responses of the two S.alfredii ecotypes to cadmium stress,which would provide further evidence for the HE S.alfredii restoration of soil cadmium pollution.关键词
超积累植物/东南景天/镉/叶绿素/光合特性/荧光参数Key words
hyperaccumulator/Sedum alfredii/cadmium/chlorophyll/photosynthetic characters/fluorescence parameter分类
农业科技引用本文复制引用
郑柳,贺雪莲,邱文敏,韩小娇,刘明英,何正权,卓仁英..镉处理后两种景天的光合相关参数变化[J].草业科学,2017,34(5):1024-1031,8.基金项目
863项目“林木抗重金属关键基因的鉴定与分子育种技术研究” （）
中央公益类科研院所专项基金 （）
“超积累植物馒头柳和东南景天耐镉的分子机制研究” （）
