摘要
采用干旱胁迫处理不同来源的披碱草属六种野生牧草幼苗,对其生长高度、相对含水量(RWC)、丙二醛(MDA)、脯氨酸(Pro)和叶绿素(Chl)含量进行测定。结果表明:供试材料幼苗生长明显受到干旱胁迫的抑制,在水分条件较好情况下老芒麦株高生长迅速,明显高于其它材料,但随着干旱胁迫的加强,干旱对幼苗生长的影响较大,而肥披碱草和紫芒披碱草受到的抑制较小。叶片RWC和Chl均随着干旱胁迫的加强呈下降趋势,其中叶片RWC下降幅度较小的为披碱草,下降较多的为肥披碱草和紫芒披碱草,而Chl含量降低较多的为麦宾草和紫芒披碱草,降低较少的为老芒麦和垂穗披碱草。MDA含量和Pro含量均随胁迫的加强呈上升趋势,MDA增加幅度较大的材料为麦宾草和紫芒披碱草,增加幅度较小的为披碱草和垂穗披碱草;Pro增幅较大的材料为紫芒披碱草和垂穗披碱草。恢复供水以后,除Pro含量持续升高外,其它指标都有不同程度的恢复。经层次聚类分析,6份材料的抗旱性可分为3类:相对抗旱材料为垂穗披碱草,中等抗旱的为肥披碱草和披碱草,相对敏感的为老芒麦、麦宾草和紫芒披碱草。
The seedlings of six wild species in Elymus were treated with drought stress, and their height, MDA, proline, and chlorophyll content were investigated. The results showed that the height was obviously reduced by drought stress. The growth rate of E. sibiricus was higher than others under no water stress. Furthermore, the drought stress had greater impact on the seedling growth of E. sibiricus and had less impact on the E. escelsus and E. purpuraristatus. With increasing drought stress, the relative water content and the total chlorophyll of all the materials decreased, while the MDA and Pro content increased. The leaf relative water content in XZD4 from Tibet decreased the lessest, E. escelsus and E. purpuraristatus from Xinjiang decreased the most; The MDA content in E. tangutorum and E. purpuraristatus increased more, while E. dahuricus and E. nutans increased less than others. The Pro content in E. purpuraristatus and E. nutans increased more. After rewatering, Pro content continued increasing, others restorated in different degrees. Through the hierarchical cluster analysis, the relative high resistance material was E. nutans, the moderate materials were E. escelsus and E. dahuricus, the low resistance materials were E. sibiricus, E. tangutorum and E. purpuraristatus.
出处
《中国草地学报》
CSCD
2008年第5期18-24,共7页
Chinese Journal of Grassland
基金
"973"计划项目"北方草地与农牧交错带生态系统维持与适应性管理的科学基础"(2007CB106806)
国家科技支撑项目"内蒙古半干旱草原区天然草地改良与人工饲草料基地建设技术集成与示范"(2006BAD16B05-4)
关键词
披碱草属
干旱胁迫
生理生态
苗期
抗旱性
Elymus
Drought stress
Eco-- physiological
Seedling stage
Drought resistance
作者简介
祁娟（1972-），女，甘肃省镇原县人，在读博士，主要从事牧草种质资源与育种方面的研究，E-mail：qijuan0622@163．com．
通讯作者，E-mail：yxuzhu@yahoo．com.
