中国岩溶2016，Vol.35Issue(6)：649-656,8.DOI:10.11932/karst20160606
麻疯树和枫杨幼苗对5种模拟喀斯特逆境的光合生理响应
Photosynthetic physiological response of Jatropha carcas and Pterocarya stenoptera seedlings to five simulated karst adversities
摘要
Abstract
The karst ecosystem is vulnerable and rocky desertification in karst regions develops rapidly.The situation of karst ecosystem becomes increasingly severe.In order to quickly build a stable forest ecosystem,it is better to select the appropriate plant species to carry out revegetation.Research on photosynthetic response traits can help to quickly identify plant adaptability to karst environment.In this study,5 different karst adversities including high pH,high bicarbonate,drought,low phosphorus (P) and low nutrient were simulated,and Hoagland solution was taken as control.Jatropha carcas and Pterocarya stenoptera seedlings were cultivated with these treatment solutions synchronously.Photosynthetic response traits of these two plant species to 5 different simulated adversities were analyzed through determining the photosynthetic characteristics and variation of stable carbon isotopic compositions (δ13 C).On the 15th day,the net photosynthetic rates (Pn) of J.carcas seedlings under alkalescent,drought,low P,high bicarbonate and low nutrient were 4.39,0.27,2.58,3.08,6.26 μtmol · m-2 · s-1,respectively.On the 25th day,the values became 4.09,0.66,4.57,3.83,4.04 μtmol · m-2 · s-1,respectively.Pn and water use efficiency (WUE) of P.stenoptera seedlings were all lower than J.carcas seedlings.Pn of P.stenoptera seedlings under alkalescent,low P,high bicarbonate and low nutrient excepted for drought condition all increased on the 25th day compared to the values on the 15th day.On 25 days from the onset of adversity treatment,WUE of J.carcas seedlings under drought stress increased significantly,and was higher than the value under other adversities.However,WUE of P.stenoptera seedlings under drought stress remained the lowest compared to the values of WUE under other adversities.Initial fluorescence (Fo) and primary conversion of light energy of PSⅡ (Fv/Fm) values in J.carcas seedlings were independent of adversities,there was no significant change.But the value of Fo of P.stenoptera seedlings under drought stress increased significantly and Fv/Fm value decreased significantly,photosynthetic apparatus of P.stenoptera seedlings suffered more serious damage under drought stress than J.carcass seedlings.On the 25th day,δ13C values of J.carcas seedlings under those adversities were more positive compared to that under control,the intracellular bicarbonate use capacity of J.carcas seedlings was higher than P.stenoptera seedlings.The utilization of two different inorganic carbon resources in J.carcas seedlings enhanced its photosynthetic carbon fixation efficiency and growth potential,improved the adaptability of J.carcas seedlings to adversities.Meanwhile,higher WUE under drought stress conditions helped improve the inorganic carbon capture efficiency of J.carcas seedlings.And the damage of drought stress on photosynthetic apparatus of these two plant species was irreversible,but J.carcas seedlings exhibited better photosynthetic capacity under drought stress conditions compared to P.stenoptera seedlings.Therefore,in the water deficit hillside environments,it is better to plant J.carcas,whereas along the river streams dank environments,it is better to plant P.stenoptera.关键词
光合作用/叶绿素荧光/水分利用效率/稳定碳同位素组成/胁迫Key words
photosynthesis/chlorophyll fluorescence/water use efficiency/stable carbon isotopic composition/stress分类
农业科技引用本文复制引用
邢德科,吴沿友,吴沿胜,于睿,黎明鸿,姚香平..麻疯树和枫杨幼苗对5种模拟喀斯特逆境的光合生理响应[J].中国岩溶,2016,35(6):649-656,8.基金项目
国家自然科学基金青年基金(31301243) （31301243）
国家重点基础研究发展计划(973)项目专题(2013CB956701) （973）
贵州省社会发展攻关项目(黔科合SY[2010]3043) （黔科合SY[2010]3043）
江苏大学引进人才科研启动基金(13JDG030) （13JDG030）
