中文摘要：

通过模拟牧草播期（4～7月份）田间土壤的自然变温和水分状况，对5种禾本科牧草萌发期的耐旱性进行了测定。测定内容包括发芽率、休眠率、死亡率和发芽指数。结果表明：（1）这5种牧草都适于在较低的温度条件下播种（5／250℃，5／300℃），即在春季和早夏播种最佳；（2）在一定的温度范围内对种子进行适当的播前抗旱锻炼（预措），有利于提高牧草在萌发期的耐旱和抗旱性能。5种牧草在萌发期耐旱性的强弱为：沙地雀麦、无芒雀麦〉披碱草〉冰草〉老芒麦。

英文摘要：

Seeds of five grasses （ Agropyron cristatum （L.） Gaern ,Elymus dahuricus turcz, Elymus sibiricus L. , Bromus ircutensis kom. and Bromus inermis leyss, ） were subjected to hydration-dehydration pre - sowing treatment by simulating soil temperature and soil water content . Germination performance of the seeds after treatments were assessed for their resistance to high temperature and drought stresses, including Ger. Dor. Dead and G. i. The results showed that the five seeds were fit for being sowed under lower temperature, such as 5/25 ℃ and 5/30 ℃. The best sowing time is in spring and early summer. With ture pre- treatments for seed in some range of temperature, drought resistance and heat resistance were improved . The results showed Brimus ircutensis kom. was the best on resistance to high temperature and drought stresses, while Elymus sibiricus L. is the poorest. The other two were in the middle.