中文摘要：

大赖草（Leymus racemosus（Lam．）Tzvel）在自然状态下结实率较高，但实生苗较少。对大赖草种子在5个温度梯度（5℃／2℃，15℃／5℃，25℃／5℃，25℃／15℃和30℃／15℃）下的萌发特征、稃和消毒处理对种子萌发的影响及种子寿命等进行了研究。结果表明：大赖草种子的最适萌发温度为25℃／15℃；稃对种子的萌发有促进作用，但效应不显著（P〉0.05）；消毒处理对种子的萌发有显著的抑制作用（P〈0.01）；低温储存条件下大赖草种子在收获24月内萌发率变化不显著（P〉0.05），而在自然生境中大赖草种子的寿命不足9个月。初步得出大赖草的种子初始萌发时间长、萌发指数低、在土壤中寿命短及生态环境的恶劣是导致大赖草在自然生境中种群更新低的主要原因。

英文摘要：

In the natural condition,Leyrnsus racernosus has a high setting rate,but its seedlings are scarcely found in each growing season. The study probed into the effects of temperature,lemma and palea＇s removal and disinfection on germination and seed longivity,and so on. Based on experiment,the optimal germination temperature for L. racernosus was 25℃/15℃. The removal of lemma and palea decreased germination index to some extent,but the effect was not significant（ P〉0.05）. Disinfection treatment could reduce germination index significantly（ P〈0. 01）. In the cold storage condition, its germination percentage didn＇t change significantly in 24 months,but its longivity couldn＇t last more than 9 months in the nature. The preliminary conclusion was drawn that the long time of seed germination, low germination index, short seed longivity in the soil as well as deteriorating living environment were the major reasons which lead to the poor renewal of L. racernosus＇ population in the nature.