淹水解除后互叶白千层幼苗光合特性的恢复  

Recovery of Photosynthetic Characteristics of Melaleuca alternifolia Seedlings after Submersion

作　　者：靖元孝[1] 刘瑞仙[1] 肖林[1] 李国梁[1] 杨丹菁[2] 

机构地区：[1]华南师范大学生命科学学院,广东省高等学校生态与环境科学重点实验室,广东广州510631 [2]广州市环境保护科学研究院,广东广州510620

出　　处：《湿地科学》2011年第4期361-366,共6页Wetland Science

基　　金：广东省科技计划项目(2005B33302014)资助

摘　　要：为了优选用于河岸、库岸等间歇性淹水地区植被恢复的适生树种,研究了30d完全淹水解除后互叶白千层(Melaleuca alternifolia)幼苗气体交换特性、叶绿素荧光特性和质膜透性的恢复情况。在全淹30d及退水后70d的恢复生长过程中,互叶白千层成活率为100%。经过30d的全淹处理,互叶白千层的叶绿素含量、净光合速率、气孔导度、蒸腾速率、光系统Ⅱ(PSⅡ)的最大光化学量子效率和光化学猝灭明显下降,而非光化学猝灭和质膜透性明显上升,分别为对照植株的51%、48%、45%、40%、86%、45%、163%和145%。在退水后的恢复生长过程中,互叶白千层的叶绿素含量、净光合速率、气孔导度、蒸腾速率、PSⅡ的最大光化学量子效率和光化学猝灭系数不断升高,而非光化学猝灭和质膜透性不断下降,60d后恢复到对照植株水平。互叶白千层是一种耐淹植物,可在河岸、库岸等间歇性淹水地区种植。Periodic flooding of trees in tropical floodplains and reservoirs where water levels fluctuate is a common phenomenon. The alternating terrestrial and aquatic periods with advancing and receding floods poses a variety of constraints to the plants growing in this habitat. If flooding is recurrent before the plants recover from previous flooding, injuries will accumulate and serious damage may occur. Therefore, when assessing plant resistance to flooding, it is important to consider the ability of plants to recover from transient waterlogging. The success of tree planting on floodplain and reservoir depends not only on the tree’s tolerance to submersion, but also on their subsequent recovery. Previous studies on physiological and growth responses of tree species to flooding have mostly focused on the responses to continuous flooding, but little is known about the responses to subsequent recovery after the removal of the flooding stress. Recovery effects of gas exchange, chlorophyll fluorescence and membrane permeability of Melaleuca alternifolia seedlings, a tall shrub species used in floodplain and reservoir forest restoration in southern China, were studied after submersion. Throughout a 30-day submersion and another 70-day recovery period, the survival rates of M. alternifolia seedlings were 100%. After 30-day submersion, pronounced decrease of chlorophyll content, net photosynthetic rate（Pn）, stomatal conductance（Gs）, transpiration rate（Tr）, the maximum quantum efficiency of the photosystemⅡ（Fv/Fm）, photochemical quenching coefficient （qP）, and increase of non-photochemical quenching （NPQ）, membrane permeability in the period after submersion, gradual increase of chlorophyll content, Pn, Gs, Tr, Fv/Fm, qP, and decrease of NPQ, membrane permeability in the recovered seedlings were found, and the above parameters in the recovered seedlings reached the levels similar to the control after 60-day recovery. Our study demonstrated that M. alternifolia seedlings is tolerant of flooding, and

关 键 词：互叶白千层 光合特性 淹水 气体交换 叶绿素荧光 恢复 

分 类 号：Q948[生物学—植物学]