摘要
为了探究油沙豆生长和光合生理过程对盐、碱复合胁迫的响应,文中以油沙豆植株为材料进行盐碱交叉胁迫的盆栽控制试验,在中性(pH≈7)和碱性(pH>8)背景下分别设置50、100、150、200、250mmol/L五个盐浓度梯度以模拟不同盐碱环境,另设置无盐碱胁迫处理作为空白对照,测定各盐碱胁迫处理下油沙豆的生长指标、光合生理参数以及叶片光合相关酶活性的变化趋势。结果表明:1)低于100mmol/L的盐浓度胁迫对油沙豆生长和生物量指标无显著影响,即油沙豆对于盐碱环境具有一定耐受性。2)盐浓度低于150mmol/L时,植株的净光合速率(Pn)、蒸腾速率(Tr)与对照组相比有所增大;盐浓度超过150mmol/L时,Pn、Tr显著降低,但胞间二氧化碳浓度(Ci)和气孔导度(Gs)无显著变化,此时非气孔限制是影响光合同化能力的主要原因。3)盐浓度低于200mmol/L时,随着盐浓度的升高,叶片PEP羧化酶和抗氧化酶POD活性均逐渐增大,盐浓度超过200mmol/L时,两种酶活性均显著降低;碱性环境下酶活性低于中性环境。4)盐、碱胁迫对油沙豆生长和光合生理过程具有交互效应。低盐浓度下,碱性环境缓解了盐胁迫的影响;高盐浓度下,碱性环境加剧了盐胁迫对油沙豆各生理过程的抑制作用。研究结果为油沙豆在我国北方盐碱地的引种栽培和管理调控提供实践支撑。
A potted control experiment was conducted for studying the effects of saline-alkali combined stress on the growth and photosynthetic physiological process of Cyperus esculentus.Five salt concentration gradients of 50,100,150,200 and 250 mmol/L in the background of neutral(pH≈7)and alkaline(pH>8)were set to simulate different stress conditions,and a saline-free treatment was set as control(CK).The growth index,photosynthetic characteristics and enzyme system activity of plants were detected,and results showed as follows:1)Compared to CK,the growth indicators of C.esculentus in low concentration of salt stress(<100 mmol/L)did not decrease significantly,which means C.esculentus had a certain degree of salt tolerance.2)The net photosynthetic rate(Pn)and stomatal conductance(Gs)of plants under<150 mmol/L salt stress gradient were higher than plants of CK.In salt stress gradient of>150 mmol/L,Pn and transpiration rate(Tr)decreased significantly,but there was no significant changes in intercellular carbon dioxide concentration(Ci)and Gs,which indicated non-stomatal limitation plays dominant role in decline of photosynthesis.3)In 0-200 mmol/L salt concentration gradients,the activities of both PEP enzyme and POD enzyme gradually increased with higher salt concentration.However,both PEP and POD significantly decreased when the salt concentration was>200 mmol/L.Enzymatic activity was lower in alkaline environment than in neutral environment.4)Salt and alkali stress had interactive effects on the growth and physiological processes of C.esculentus.In the low concentration salt stress condition,alkaline alleviated the impact of salt stress on C.esculentus.In the high concentration salt stress condition,alkaline exacerbated the inhibitory effect of salt stress on C.esculentus.This study provided a theoretical basis for the introduction of C.esculentus in saline land in northern China,and a reference for cultivation and management of C.esculentus.
作者
王艺臻
丁国栋
崔欣然
于明含
张琳琳
WANG Yizhen;DING Guodong;CUI Xinran;YU Minghan;ZHANG Linlin(Key Laboratory of State Forestry Administration on Soil and Water Conservation,Beijing Forestry University,Beijing 100083;Yanchi Ecology Research Station of the Mu Us Desert,Yanchi 751500,China)
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2022年第5期146-152,共7页
Journal of Arid Land Resources and Environment
基金
国家重点研发计划课题(2019YFC0507601)资助。
关键词
油沙豆
盐碱胁迫
光合特性
酶活性
Cyperus esculentus
saline-alkali stress
photosynthetic characteristics
enzymatic
