生态学杂志2024，Vol.43Issue(11)：3255-3265,11.DOI:10.13292/j.1000-4890.202411.034
褪黑素对镉胁迫下蒿柳光合速率下降的缓解效应
Alleviation effect of melatonin on degressive photosynthetic rate in Salix viminalis exposed to cadmium
摘要
Abstract
Salix viminalis has an outstanding capacity to accumulate cadmium(Cd),but with poor tolerance to high concentrations of Cd.Investigating the regulation function of melatonin(MT)on photosynthetic rate of S.vimi-nalis exposed to high concentrations of Cd would help reveal the alleviation effect of MT on woody plants exposed to Cd and provide supporting measures for phytoremediation of heavy metals.Cutting seedlings of clonal S.viminalis were used as experimental material.Three treatments were set as blank(BT),Cd stress(CT),and foliar spraying MT followed by Cd stress(MCT).We examined the regulatory modes of MT on photosynthetic gas exchange param-eters,chlorophyll fluorescence parameters under dynamic light,and the content of ribulose-1,5-bisphosphate car-boxylase/oxygenase(Rubisco)in S.viminalis under Cd stress.The chlorophyll a(Chla)and Rubisco contents of S.viminalis exposed to Cd were decreased by 20％and 21％on the 7th day after treatment,respectively.The chlo-rophyll b(Chlb),stomatal conductance(Gs),intercellular CO2 concentration(Ci),net photosynthetic rate(Pn)of S.viminalis exposed to Cd were decreased by 32％,35％,23％,21％on the 14th day after treatment.Under the treatment of spraying 50 µmol·L-1 MT,Chl a,Chlb Gs,Ci,Rubisco content were increased by 30％,28％,47％,35％,25％respectively.Pn and photosystem Ⅱ(PS Ⅱ)maximum photochemical effiiciency(Fv/Fm)of S.viminalis exposed to Cd stress were decreased by 36％and 16％on the 21st day after treatment.After MT spra-ying,Pn and Fv/Fm were increased by 39％and 13％,respectively.Photoinhibition of S.viminalis exposed to Cd was aggravated,while spraying MT alleviated its photoinhibition.Under Cd stress,MT promoted photosynthetic gas exchange of S.viminalis by increasing stomatal conductance,promoted light harvesting by maintaining chlorophyll concentration,improved photosynthetic capacity by enhancing light energy conversion efficiency and photosynthetic electron transfer rate,and promoted C02 assimilation by increasing Rubisco content.Moreover,MT promoted growth of S.viminalis exposed to Cd stress by increasing photosynthetic intensity.关键词
褪黑素/镉(Cd)/蒿柳/光合速率Key words
melatonin/cadmium(Cd)/Salix viminalis/photosynthesis rate引用本文复制引用
殷佳慧,李霞,邹竣竹,巨关升,宁崴,李奥,王元成,孙振元..褪黑素对镉胁迫下蒿柳光合速率下降的缓解效应[J].生态学杂志,2024,43(11):3255-3265,11.基金项目
吉林省自然科学基金(联合基金项目)资助项目"基于镉污染植物修复的长白山区蒿柳资源评价及研究"(YDZJ202101ZYTS113)和山东省自然科学基金重点项目"蒿柳-丛枝菌根真菌修复多环芳烃污染土壤的协同强化机制研究"(ZR2020KC020)资助. （联合基金项目）
