Abstract: In order to explore the effect of cross sowing in different sowing dates of Elymus nutans and Medicago sativa,and the effect of the planting mode on the growth of Elymus nutans,Elymus nutans and Medicago sativa were selected as materials and the study was conducted in the Zhangjiakou experiment Station of National forage industry system. Elymus nutans was planted first,after which the alfalfa was planted vertically with artificial furrowing every 15 days. Four sowing dates were set for treatments. Coverage,yield and quality of Elymus nutans heading period were measured. The result showed that,cross sowing with alfalfa after 15 days of Elymus nutans sowing,and sowing the both at the same time,will effect the growth of Elymus,but these two sowing treatments can significantly improve the vegetation coverage,forage yield and forage quality in the year of grassland establishment. Cross sowing with alfalfa after 30 days of Elymus nutans sowing,Elymus nutans will dominant in the cross sowing combination,the total forage yield and forage quality decreased. When establishing artificial grassland in Bashang area of Zhangjiakou,it is better to plant Elymus nutans at first and plant alfalfa within 30 days.

Key words: Medicago sativa, Elymus nutans, Mixed sowing, Yield, Quality

摘要： 为探讨不同播期下垂穗披碱草（Elymus nutans）与紫花苜蓿（Medicago sativa）交叉混播效果及该种植模式对垂穗披碱草生长的影响，本研究以垂穗披碱草与紫花苜蓿为材料在国家牧草体系张家口试验站开展试验研究。试验先机播垂穗披碱草，同时在其播种行人工开沟交叉播种紫花苜蓿，设15 d为1个紫花苜蓿播期，共4个播期处理，在垂穗披碱草抽穗期测定植物盖度、产量及品质。结果表明：垂穗披碱草播种后15 d混播紫花苜蓿及与紫花苜蓿同期交叉混播会影响垂穗披碱草的生长，但这两播期处理在草地建植当年可以显著提高植被盖度、产量和品质；垂穗披碱草播种30 d后与紫花苜蓿交叉混播，混播组合中垂穗披碱草占优势且牧草总产量及饲草品质下降。建议在张家口坝上地区建立人工草地时，先播种垂穗披碱草，30天内补播紫花苜蓿效果较好。

关键词: 紫花苜蓿, 垂穗披碱草, 混播, 产量, 品质