Abstract: Using the method of PEG-6000 to simulate drought stress,the germination rate and germination index and other indexes of ten herbaceous plant seeds growing in Ningxia coal base after preliminary investigation were measured to compare their drought resistance during germination. The results showed that different PEG concentrations treatments had different effects on seed germination of herbaceous plants. With the increase of PEG drought stress degree,the germination potential,germination rate,germination index,radicle length and radicle diameter of seeds decreased generally;Among them,PEG (5%) with low concentration had obvious promoting effects on the germination potential of Astragalus adsurgens Pall.the germination rate of Artemisia desertorum Spreng. Syst. Veg.,the radicle length of Glycyrrhiza uralensis Fisch. and the radicle diameter of Althaea rosea (Linn.) Cavan. Compared with the control,under the treatment with PEG concentration of 15%,the germination rate and germination potential of Medicago sativa L.,Althaea rosea (Linn.) Cavan. and Trifolium repens L. decreased greatly;When the PEG concentration was 20%,the germination rate and germination potential of Sophora alopecuroides L.,Medicago sativa L.,Suaedaglauca (Bunge) Bunge.,and Trifolium repens L. were greatly reduced. The method of membership function was used to evaluate the drought resistance of ten herbaceous plants in germination period,the order of drought resistance was Glycyrrhiza uralensis Fisch. > Melilotus suaveolens Ledeb. > Suaedaglauca (Bunge) Bunge. > Agriophyllum squarrosum (Linn.) Moq. > Medicago sativa L. > Sophora alopecuroides L. > Artemisia desertorum Spreng. Syst. Veg. > Astragalus adsurgens Pall. > Althaea rosea (Linn.) Cavan. > Trifolium repens L..

Key words: Herbaceous plants, PEG stress, Germination index, Membership function, Drought resistance

摘要： 本研究采用聚乙二醇（Polyethylene glycol，PEG-6000）模拟干旱胁迫的方法，测定10种生长分布在宁夏煤炭基地的草本植物种子在干旱胁迫下的萌芽率、发芽指数等指标，旨在比较其萌发期的抗旱性。结果表明：不同PEG浓度处理对草本植物种子萌发的影响不同。随着PEG浓度的增加，种子的发芽势、发芽率、发芽指数、幼苗胚根长和胚根粗总体上呈降低趋势；其中低浓度PEG（5%）胁迫处理，对沙打旺（Astragalus adsurgens Pall.）的发芽势、沙蒿（Artemisia desertorum Spreng.Syst.Veg.）的发芽率、甘草（Glycyrrhiza uralensis Fisch.）的胚根长以及蜀葵（Althaea rosea（Linn.）Cavan.）的胚根粗等具有明显的促进作用；与对照相比，在PEG浓度为15%的处理下，紫花苜蓿（Medicago sativa L.）、蜀葵、白三叶（Trifolium repens L.）的发芽率、发芽势下降幅度最大；PEG浓度为20%时，苦豆子（Sophora alopecuroides L.）、紫花苜蓿、碱蓬（Suaeda glauca （Bunge） Bunge.）、白三叶的发芽率、发芽势下降幅度最大。采用隶属函数法对10种草本植物的萌发期抗旱性进行综合评价，其抗旱性顺序为：甘草 > 草木樨（Melilotus suaveolens Ledeb.） > 碱蓬 > 沙米（Agriophyllum squarrosum （Linn.） Moq.） > 紫花苜蓿 > 苦豆子 > 沙蒿 > 沙打旺 > 蜀葵 > 白三叶。

关键词: 草本植物, PEG干旱胁迫, 发芽指数, 隶属函数, 抗旱性