盐碱胁迫对喜树幼苗生长及体内离子选择性运输的影响  

Effects of Saline and Alkali Stresses on Growth and Mineral Nutrition Selective Transportation of Camptotheca acuminata Decne

作　　者：郁万文[1] 曹福亮[1] 蔡金峰[1] 高长忠 

机构地区：[1]南京林业大学,南京210037 [2]盐城市红多草莓专业合作社

出　　处：《东北林业大学学报》2015年第11期1-5,共5页Journal of Northeast Forestry University

基　　金：苏北科技发展计划--科技富民强县项目(BN2014137);江苏高校优势学科建设工程资助项目

摘　　要：研究了Na+等质量分数下中性盐(Na Cl和Na2SO4)与碱性盐(Na HCO3和Na2CO3)对喜树幼苗生物量、体内离子选择性运输效应。结果表明:盐碱胁迫抑制了喜树根、茎生物量的积累;高浓度中性盐使叶生物量增加,高浓度碱性盐使叶生物量大幅降低;碱性盐对生物量的影响大于中性盐。盐碱胁迫使喜树体内Na+质量分数显著升高,使K+上运、Ca2+下运,且随着胁迫强度增强而加剧,其中碱性盐对体内Na+、K+、Ca2+质量分数的影响较大。盐碱胁迫降低了根、茎、叶中K+质量分数/Na+质量分数、Ca2+质量分数/Na+质量分数,且随着中性盐(Na Cl和Na2SO4)与碱性盐(Na HCO3和Na2CO3)质量分数增加其K+质量分数/Na+质量分数、Ca2+质量分数/Na+质量分数降低幅度增加,其影响程度由小到大的顺序为Na2SO4、Na Cl、Na HCO3、Na2CO3。盐碱胁迫降低了K+、Ca2+由根向茎中选择性运输的能力,增加了叶对K+、Ca2+的选择性吸收。中性盐对K+、Ca2+由根向茎选择性运输能力的影响低于碱性盐,但对由茎向叶中选择运输K+、Ca2+的能力的影响与之相反。总之,喜树在低强度盐碱胁迫下通过牺牲根、茎生物量积累维持叶的生长来稀释叶中迅速累积的Na+,同时通过吸收Na+降低渗透势维持对水分和矿质元素的吸收,另外,通过提高向叶中运输K+部分消除叶中的Na+毒害,又通过向根中运输Ca2+部分消除根中的Na+毒害,表现出一定的主动适应性。We studied the biomass,Na^＋,K^＋and Ca^2＋mass fractions and ionic selective transportation and distribution of organ and tissue levels in Camptotheca acuminata seedlings exposed to conditions of the same Na^＋mass fraction for understanding the responses of plants to salt and alkali stresses. The salt and alkali stresses inhibited the accumulation of root and stem biomass,and neutral salt in high concentration increased leaf biomass,and alkali salt in high concentration significantly decreased leaf biomass. The effect of alkali stress on the biomass accumulation was bigger than that of salt stress. Na^＋mass fractions of root,stem and leaf in seedlings remarkably increased under salt and alkali stresses,and the effects of NaCl and Na2SO4 stresses on Na^＋mass fraction were smaller than those of NaH CO3 and Na2CO3. Salt and alkali stresses made K^＋transport from root to leaf,and Ca^2＋transport from leaf to root which exacerbated with the increase of stress intensity,and the effects of K^＋and Ca^2＋transportation on alkali stress were bigger than those on salt stress. Salt and alkali stresses made K^＋/ Na^＋,Ca^2＋/ Na^＋of root,stem and leaf decrease which was exacerbated as the salt and alkali mass fractions increased.The order of the effects of K^＋/ Na^＋,Ca^2＋/ Na^＋of root,stem and leaf from small to big was Na2SO4,NaCl,NaH CO3 and Na2CO3. The ability of K^＋,Ca^2＋selective transportation from root to stem decreased and the ability of leaf K^＋,Ca^2＋selective absorption increased under salt and alkali stresses. The effects of the ability of K^＋,Ca^2＋selective transportation from root to stem on NaCl and Na2SO4 stresses were smaller than those on NaH CO3 and Na2CO3stresses,but the effects of the ability of leaf K^＋,Ca^2＋selective absorption under salt and alkali stresses was opposite. Under low salt and alkali stresses,Camptotheca acuminata maintained leaf growth to dilute rapidly elevating Na^＋by decreasing the accumulation of root and stem biomass,and maintained the a

关 键 词：盐碱胁迫 喜树 矿质营养 选择性吸收和运输 

分 类 号：Q945.78[生物学—植物学]