Abstract: The height increased fashion of Bromus inermis Leyss and Medicago varia Marein,cv. Cao yuan No.2 not by different proportion of mix sowing,the regression curves equation of height increased of B.inermis and M.varia is H=a+bt+ct²(H is height,t is time of growing).The curves equation of biomass accumulation of Medicago is W=atb, fashion of above ground biomass accumulation of B.inermis in single sowing is W=ae^bt and in mix sowing is W=atb,rate of increased of biomass are different on mix sowing of different proportion.Single sowing and mix sowing different proportion have different structure of biomass and leave were distributed in different space.The stem/leave value,LAI are different on different district.LAI of Medicago is more than LAI of B.inermis . There were the much increased in biomass of community by sowing than natural grassland. The crude fat,crude fibre,crude ash content. The energy and DE in mix sowing are more than single sowing,The crude protein and digestible protein in mix sowing lower than single sowing Medicago but more than single sowing B.inermis. The biggest biomass in producted in district of density proportion 1/1(B.inermis/Medicago, sowing seed weight 30kg/hm²;10kg/hm²).

Key words: Mix sowing composition, Bromus inermis, Medicago varia

摘要： 研究无芒雀麦与草原二号苜蓿的混播比例、株高和地上生物量积累动态。结果表明,无芒雀麦和苜蓿的生长高度模式不受单播、混播的影响,其增长曲线为H=a+bt+ct²。苜蓿地上生物量积累模式不受单播、混播的影响,其增长曲线为W=at^b。无芒雀麦地上生物量积累模式在单、混播中分别为W=ae^bt和W=at^b。单播及不同比例的混播组合,其地上生物量结构各异。生物量和叶片集中分布的空间不同。茎/叶、叶面积指在不同数混播小区的数值各异。苜蓿的叶面积指数大于无芒雀麦。混播较天然草原有显著或极显著的增产作用。且混播较单播增产显著。混播区的粗脂肪、粗纤维、粗灰分、总能和可消化能含量均高于单播,而粗蛋白质、可消化蛋白质则低于单播苜蓿,但高于单播无芒雀麦。无芒雀麦与苜蓿越冬苗的比例为1∶1,生物量比1∶1(播种量30kg和10kg/hm²)为优化组合。

关键词: 无芒雀麦, 苜蓿, 混播组合