盐碱胁迫对紫花苜蓿种子发芽的协同影响  

Synergistic Effects of Salt and Alkaline Stresses on the Seed Germination of Medicago sativa

作　　者：蔺吉祥[1] 高战武[2] 王颖[3] 于兴洋[4] 邵帅[1] 李晓宇[4] 

机构地区：[1]东北林业大学盐碱地生物资源环境研究中心东北油田盐碱植被恢复与重建教育部重点实验室,黑龙江哈尔滨150040 [2]白城师范学院地理系,吉林白城137000 [3]吉林建筑大学松辽流域水环境教育部重点实验室,吉林长春130118 [4]中国科学院东北地理与农业生态研究所,吉林长春130024

出　　处：《草地学报》2014年第2期312-318,共7页Acta Agrestia Sinica

基　　金：中央高校基本科研业务费专项资金(DL12BA32)(2572014EA04);哈尔滨市科技创新人才专项基金(2013RFQXJ022)资助

摘　　要：以紫花苜蓿(Medicago sativa)为材料,在实验室内模拟土壤复杂盐碱逆境条件,将2种中性盐NaCl,Na_2SO_4与2种碱性盐NaHCO_3,Na_2CO_3以不同的摩尔比例混合,按碱性盐比例递增的顺序共设置A^F组,同时每个组又设置6种盐浓度(24~168 mM),涵盖Na+浓度为32~192 mM,pH为7.03~10.68范围的盐碱生境,试验共模拟出36种盐度和碱度(pH值)各不相同的盐碱条件,并对胁迫下苜蓿种子发芽指标进行了测定。结果表明:低浓度胁迫对苜蓿种子发芽有一定的促进作用,在各胁迫处理组下苜蓿种子的发芽指标(发芽率、发芽势、发芽指数和活力指数)均随着盐浓度的增加不断下降,且碱性盐比例越大下降越明显,而平均发芽天数逐渐增加。胚根与胚芽生长表现出与发芽相似的变化规律,并且胚根适应盐碱能力更强。因此,复合盐碱胁迫不同于单独的盐或碱胁迫,一旦浓度较高时,盐和碱的交互作用更明显,二者存在明显的协同作用,加剧了对植物的伤害。Alfalfa （Medicago sativa） was taken as research material.Saline stress was simulated by mixing NaCl and Na2SO4 in different molar ratios.Similarly,alkaline stress was simulated by mixing NaHCO3and Na2CO3 with different molar ratios.Six groups （A to F） with different Na＋ concentrations and pH values were designed.Results showed that the germination rate of alfalfa seed was promoted by lower concentration.The germination indices of alfalfa seed （germination rate,germination energy,germination index and vigor index） were all decreased with the increase of salinity and the decreasing degree were more obvious with increasing the proportion of alkaline salt,whereas mean germination days were increased.Radicle was more tolerant to saline and alkaline stresses compared with embryo.These data indicated that the mixed salinity-alkalinity stresses were different from either saline or alkaline stress.The interactions of saline and alkaline stresses increased with the increase of salt concentration.Plant was damaged severely by the synergy of both stresses.

关 键 词：紫花苜蓿 种子 盐碱胁迫 发芽率 发芽势 

分 类 号：Q945.78[生物学—植物学]