外源褪黑素对盐胁迫下石榴幼苗光合及抗氧化特性的影响  

Effects of exogenous melatonin on photosynthetic and antioxidant properties of young seedlings under salt stress conditions in pomegranate

作　　者：杨元玲 刘慧英[1] 关思慧 柴亚倩 盖昊圣 刘明轩 刘阳 刁明[1] YANG Yuanling;LIU Huiying;GUAN Sihui;CHAI Yaqian;GAI Haosheng;LIU Mingxuan;LIU Yang;DIAO Ming(School of Agriculture,Shihezi University/Key Laboratory of Cultivation Physiology and Germplasm Resource Utilization of Specialty Fruits and Vegetables,Xinjiang Production and Construction Corps,Shihezi 832003,Xinjiang,China)

机构地区：[1]石河子大学农学院·新疆生产建设兵团特色果蔬栽培生理与种质资源利用重点实验室,新疆石河子832003

出　　处：《果树学报》2025年第2期360-375,共16页Journal of Fruit Science

基　　金：新疆生产建设兵团科技攻关重点项目(2021AB015)。

摘　　要：【目的】探明外源褪黑素(MT)处理对盐胁迫下石榴(Punica granatum L.)幼苗光合特性及抗氧化能力的影响,筛选出缓解盐胁迫的适宜MT浓度。【方法】以突尼斯软籽(敏盐)和叶城酸石榴(耐盐)为试材,采用基质盆栽的方法,设置对照、盐胁迫(200 mmol·L^(-1)Na Cl)及盐胁迫下分别喷施50、100、200、400μmol·L^(-1)MT共6个处理,研究不同浓度MT处理对盐胁迫5、10、15 d后两个品种叶片光合气体交换参数、叶绿素荧光、叶绿素含量及抗氧化能力的影响。【结果】200μmol·L^(-1)盐胁迫导致2个品种的光合和抗氧化能力均下降,而施用适宜浓度(100、200μmol·L^(-1))的外源MT可显著提高盐胁迫下两个品种叶片的光合气体交换参数(P_n、Gs、Tr)、荧光参数(F_(v)/F_(m)、q P、Y_(Ⅱ)),降低电解质外渗(REC),减少丙二醛含量(MDA),提高抗氧化物酶(SOD、POD、CAT)活性。但高浓度(400μmol·L^(-1))外源MT会进一步加剧氧化胁迫和渗透胁迫,导致幼苗的光合能力受抑。【结论】综合评价表明,分别外施200、100μmol·L^(-1)MT对缓解突尼斯软籽和叶城酸石榴遭受盐胁迫伤害的效果最佳。【Objective】The pomegranate,a significant economic forest fruit crop predominantly cultivated in Northwest China,is favored by consumers due to its extensive nutritional and medicinal benefits.However,the escalating issue of land salinization has resulted in reduced pomegranate yields and diminished fruit quality,thereby significantly hindering the advancement of the pomegranate industry.While the selection and breeding of salt-tolerant plants,along with the application of transgenic plants,represent crucial strategies for enhancing and utilizing saline soils,these methods are constrained by their prolonged duration and inherent challenges.In recent years,melatonin(MT)has emerged as a significant phytohormone capable of mitigating the detrimental effects of salt stress on plants.This study aims to examine the impact of exogenous MT on the photosynthetic characteristics and antioxidant capacity of pomegranate(Punica granatum L.)seedlings subjected to salt stress,with a focus on identifying the optimal concentration for alleviating such stress.【Methods】Tunisian Soft-seeded(salt-sensitive)and Yecheng Acid(salt-tolerant)pomegranates were used as test materials,and the potting culture with substrate(vermiculite∶perlite∶grass charcoal=1∶1∶1,V/V/V).was adopted Six treatments were set up,namely,non-salt stress(CK),200 mmol·L^(-1) NaCl(T1),200 mmol·L^(-1) NaCl+50μmol·L^(-1) MT(T2),200 mmol·L^(-1) NaCl+100μmol·L^(-1) MT(T3),200 mmol·L^(-1) NaCl+150μmol·L^(-1) MT(T4),and 200 mmol·L^(-1) NaCl+200μmol·L^(-1) MT(T5)to investigate the effects of different concentrations of MT treatments.This study examined the impact of varying concentrations of melatonin(MT)on chlorophyll content,photosynthetic gas exchange parameters,chlorophyll fluorescence,osmoregulatory substances and antioxidant capacity in the leaves of two pomegranate seedling cultivars over treating durations of 5,10 and 15 days.Additionally,to identify key physiological indicators of exogenous MT effects on pomegranate seedlings under salt

关 键 词：石榴 褪黑素 盐胁迫 光合特性 抗氧化特性 综合评价 

分 类 号：S665.4[农业科学—果树学]