桫椤光合特性和水势对干旱胁迫及复水的响应  

Responses of Photosynthetic Characteristics and Water Potential of Alsophila spinulosa to Drought Stress and Rehydration

作　　者：吕朝燕[1,2] 高智席[1,2] 徐兴线 吴焕 陈兴艳 LV Chaoyan;GAO Zhixi;XU Xingxian;WU Huan;CHEN Xingyan(School of Biological and Agricultural Technology,Zunyi Normal College,Zunyi,Guizhou 563006,China;Institute of Food Green Processing and Nutrition Control Engineering,Zunyi Normal College,Zunyi,Guizhou 563006,China)

机构地区：[1]遵义师范学院生物与农业科技学院,贵州遵义563006 [2]遵义师范学院食品绿色化加工与营养调控工程研究所,贵州遵义563006

出　　处：《林业资源管理》2023年第1期51-61,共11页Forest Resources Management

基　　金：国家自然科学基金项目(32260383);贵州省科技计划项目(黔科合基础-ZK﹝2022﹞一般574);遵义师范学院学术新苗培养及创新探索培育项目(黔科合平台人才[2017年]5727-17号)。

摘　　要：为了弄清木本蕨类植物对干旱胁迫的适应能力,选用3a生桫椤苗,通过盆栽控水对其进行干旱胁迫和复水处理,研究了干旱历时3,6,9,12d和复水历时3,6,9d时桫椤叶片水势和光合作用的变化情况。结果表明,随干旱时间的延长,桫椤叶片水势整体呈升高趋势,净光合速率(P_(n))呈下降趋势,胞间CO_(2)浓度(C_(i))呈先降低后升高的趋势,气孔导度(G_(s))和蒸腾速率(T_(r))呈降低—升高—降低的趋势。干旱初期(6d前),P_(n)与G_(s),C_(i)变化趋势基本一致,P_(n)的下降主要由气孔限制引起。而干旱后期(6d后),P_(n)与G_(s),C_(i)变化趋势不一致,P_(n)的下降主要由非气孔限制引发。复水后,桫椤叶片P_(n)和T_(r)基本恢复到了充分供水时的水平,而水势、G_(s)和C_(i)恢复到了充分供水时以上的水平。同时,桫椤叶片水分利用效率(WUE)随干旱时间的延长呈先升高后降低的趋势,在干旱6d后即呈下降趋势,且复水后,桫椤叶片WUE基本恢复到了充分供水时的水平。综合来看,桫椤具有相对较差的干旱耐受能力和相对较强的复水恢复能力。并且,通过干旱胁迫和复水过程光合生理特征的综合分析,初步认为桫椤属于干旱避免型植物。In order to clarify the adaptability of woody ferns to drought stress,3-year-old Alsophila spinulosa seedlings were selected for drought stress and rehydration treatment through potted water control.The changes of water potential and photosynthesis in the leaves of Alsophila spinulosa were studied after 3,6,9,12 days of drought and after 3,6,and 9 days of rehydration.The results showed that with the prolongation of drought time,the water potential of Alsophila spinulosa leaves showed an overall upward trend,the net photosynthetic rate(P_(n))showed a downward trend,the inter-CO_(2)concentration(C_(i))first decreased and then increased,and the stomatal conductance(G_(s))and transpiration rate(T_(r))showed a trend of decreasing-increasing-decreasing.In the early stage of drought(6 days ago),the change trend of P_(n),G_(s)and C_(i)was basically the same,and the decrease of P_(n)was mainly caused by stomatal limitation.In the later period of drought(after 6 days),the change trend of P_(n)was inconsistent with that of G_(s)and C_(i),and the decrease of P_(n)was mainly caused by non-stomatal limitation.After rehydration,P_(n)and T_(r) of Alsophila spinulosa leaves recovered to the level of adequate water supply,while the water potential,G_(s)and C_(i)recovered to the level above that of adequate water supply.At the same time,the water use efficiency(WUE)of Alsophila spinulosa leaves increased first and then decreased with the prolongation of drought time,and showed a downward trend after 6 days of drought.And after rehydration,the WUE basically recovered to the level of adequate water supply.Taken together,Alsophila spinulosa has relatively poor drought tolerance and relatively strong rehydration recovery ability.Through the analysis of the photosynthetic physiological characteristics of drought stress and rehydration process,it is preliminarily considered that Alsophila spinulosa is a drought-avoiding plant.

关 键 词：桫椤 光合作用 干旱胁迫 复水 水分利用效率 水势 

分 类 号：Q945[生物学—植物学]