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研究了温度(恒温和变温)、水分(含水量2.5%–40.0%)和干旱胁迫、土壤类型(盐碱土和非盐碱土)和盐碱胁迫(NaCl和Na2CO3)等环境因子对羊草(Leymus chinensis)种子萌发的影响。恒温下未经打破休眠处理的羊草种子发芽率不足2%,变温下羊草种子发芽率可达85.3%,表明温度是影响羊草种子萌发的关键因素之一。羊草种子萌发的适宜土壤含水量为2.5%–15.0%,随着含水量继续增加,发芽率呈下降趋势。松嫩平原盐碱化土壤对羊草种子萌发具有显著的抑制作用,羊草种子在重度盐碱土(pH10.24)中发芽率仅为6.0%,而在非盐碱土中发芽率可达61.3%。羊草种子在萌发阶段的耐盐碱能力差,随着NaCl和Na2CO3浓度增加,发芽率呈显著下降趋势,且Na2CO3的抑制作用更强。松嫩平原盐碱环境下羊草种子萌发受到抑制是该地区羊草草地退化的原因之一。
The effect of environmental factors (temperature and temperature, water content (2.5% -40.0%) and drought stress, soil type (saline-alkali soil and non-saline soil) and saline-alkali stress chinensis) seed germination. The germination rate of Leymus chinensis seeds without humus treatment at constant temperature was less than 2%, and the germination rate of Leymus chinensis seeds reached 85.3% under the temperature change, indicating that temperature is one of the key factors that affect the germination of Leymus chinensis seeds. The suitable soil moisture content of the seed germination of Leymus chinensis was 2.5% -15.0%. With the water content increasing, the germination rate decreased. The salinized soils of the Songnen Plain had a significant inhibitory effect on the seed germination of Leymus chinensis. The germination rate of Leymus chinensis seeds was only 6.0% in severe saline-alkaline soil (pH10.24), while the germination rate in non-saline-alkali soil was 61.3% . The seedling of Leymus chinensis had poor salt-tolerance ability in germination stage. With the increase of NaCl and Na2CO3 concentration, the germination rate decreased significantly and the inhibition effect of Na2CO3 was stronger. The inhibition of the seed germination of Leymus chinensis in saline-alkali environment in the Songnen Plain is one of the reasons for the degeneration of Leymus chinensis grassland in the area.