Na_(2)SO_(4)和Na_(2)CO_(3)胁迫对苦楝幼苗渗透调节特性和离子分配的影响  

Effects of Na_(2)SO_(4) or Na_(2)CO_(3) on osmotic regulation characteristics and ion distribution in Melia azedarach seedlings

作　　者：张远兰[1,2] 胡鑫 郁万文 国靖[1,2] 蔡金峰 曹福亮[1,2] 汪贵斌 ZHANG Yuanlan;HU Xin;YU Wanwen;GUO Jing;CAI Jinfeng;CAO Fuliang;WANG Guibin(Co-Innovation Center for the Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing 210037,Jiangsu,China;College of Forestry,Nanjing Forestry University,Nanjing 210037,Jiangsu,China)

机构地区：[1]南京林业大学南方现代林业协同创新中心,江苏南京210037 [2]南京林业大学林学院,江苏南京210037

出　　处：《中南林业科技大学学报》2021年第4期76-85,共10页Journal of Central South University of Forestry & Technology

基　　金：国家重点研发计划项目(2017YFD06000700);江苏省农业科技自主创新基金项目(CX(16)1005);江苏高校优势学科建设工程资助项目(PAPD)。

摘　　要：【目的】探究不同浓度中性盐或碱性盐处理对苦楝幼苗渗透调节特性和离子分配的影响,以了解苦楝在幼苗生长阶段对盐碱胁迫的响应。【方法】以1年生苦楝Melia azedarach实生苗为材料,通过设置中性盐Na2SO4和碱性盐Na2CO33个浓度(200、400和600 mmol·L^(-1))处理40 d,研究苦楝渗透调节物质含量、抗氧化酶活性及离子分布的差异。【结果】苦楝叶片游离脯氨酸和可溶性蛋白含量在低盐浓度(200 mmol·L^(-1))随时间延长呈递增趋势,在中、高盐浓度(400和600 mmol·L^(-1))呈先升后降的变化趋势。可溶性糖含量、超氧化物歧化酶(SOD)酶活性和过氧化物酶(POD)酶活性在3种盐浓度均是随时间延长呈先升后降的趋势,且碱性盐对苦楝幼苗可溶性糖含量和酶活性的影响更大。盐胁迫下苦楝根、茎和叶中Na+含量均随盐浓度的升高而上升,Na+在各器官中的分布总体上呈叶>茎>根的趋势。200 mmol·L^(-1)浓度中性盐处理促进了苦楝根和叶中K+的积累,在400和600 mmol·L^(-1)浓度下,两种盐对根和叶中K+的积累均起到显著的抑制作用,碱性盐比中性盐的抑制作用更强。苦楝根、茎和叶中K+/Na+整体上随盐浓度的升高而呈下降的趋势,且盐浓度越高,下降程度越大。【结论】苦楝幼苗遭受盐胁迫时,渗透调节起重要作用,碱性盐对苦楝幼苗的影响大于中性盐,苦楝具有一定的耐盐碱能力,可作为低盐土壤环境改良树种引种栽培。【Objective】To investigate the response of Melia azedarach to saline-alkali stress in seedling growth stage,the effects of neutral or alkaline salt stress on osmotic regulation and ion distribution of Melia azedarach seedlings were studied.【Method】Three salt concentrations(200,400 and 600 mmol·L^(-1))of neutral salt(Na2SO4)or alkaline salt(Na2CO3)were set up to study osmotic regulation and ion distribution of Melia azedarach seedlings for 40 days in greenhouse.【Result】Consistent growth in proline and soluble protein contents are observed under low salt concentration(200 mmol·L^(-1))and they increased first and then decline at medium and high salt concentrations(400 and 600 mmol·L^(-1)).The soluble sugar content,superoxide dismutase(SOD)activities and peroxidase(POD)activities in Melia azedarach seedling leaves increase firstly and then decrease.The fluctuation of SOD activity increases with the increase of salt concentration.And the effects of alkaline salt on SOD and POD activities are greater.Na+content in root,stem and leaf increase with the increase of salt concentration.The distribution of Na+in all organs show the trend of leaf>stem>root.The accumulation of K+in root and leaf is promoted by 200 mmol·L^(-1)neutral salt stress.However,under 400 and 600 mmol·L^(-1)salt treatments,the accumulation of K+in root and leaf are significantly inhibited,and the inhibitory effect of alkaline salt is greater than that of neutral salt.K+/Na+in root,stem and leaf decrease with the increase of salt concentration,and the higher salt concentration,the greater the difference.【Conclusion】Osmotic regulation plays an important role under salt stress of Melia azedarach seedlings,and the effect of alkaline salt on Melia azedarach seedlings is greater than that of neutral salt.Melia azedarach has certain salt and alkali tolerance,and can be introduced and cultivated as tree species for improving low-salt soil environment.

关 键 词：苦楝 盐碱胁迫 渗透调节 离子分布 

分 类 号：S718.43[农业科学—林学]