Abstract: The objective of this study was to identify the effects of legume-grass mixtures of Avena sativa and Vicia sativa on the characters of plant growth by analyzing the shoot biomass,morphological characteristic,and interspecific relationship of the pasture. The results showed that the interspecific competition appeared at the flowering stage of oats in the mixed grassland as the relative yield total value of pasture less than 1.0. The yield of pasture varied with stages of plant growth. The yield of oat and vetch pea 2:1 mixture was the highest (1 576.7 g·m^-2) at the milk stage (6^th September) of oats,and the yield was significantly different with other treatments except for the oat and vetch pea 1:2 mixture. The highest yield (1 766.7 g·m^-2) at the maturity stage (29^th September) of oats was found in the oat monoculture treatment. And compared to monoculture treatment,the height of legume-grass mixtures treatments increased by 12.7~28.3%,and increased by 1~2 for the number of tillers. On the contrary,the legume-grass mixtures treatments reduced the height and branches of vetch pea. We suggest that the optimal mixture ratio of oat and vetch pea for legume-grass mixtures is 2:1 for making hay,and harvesting at maturity stage is highly recommended.

Key words: Mixed sowing, Shoot biomass, Plant height, Tiller/Branch

摘要： 本试验以不同混播比例燕麦（Avena sativa）和箭筈豌豆（Vicia sativa）混播草地为研究对象，通过对混播草地植物生物量、形态特征及种间关系的测定分析，探讨不同禾豆混播比例对植物生长特性的影响。结果表明：在燕麦开花期（8月17日），混播系统相对产量总和显著小于1.0（P<0.05），两种植物表现出明显的种间竞争关系。不同混播处理草地生物量因生育期而异，在燕麦乳熟期（9月6日），燕麦和箭筈豌豆以2：1混播干物质产量最高（1 576.7 g·m^-2），除与燕麦和箭筈豌豆以1：2混播处理差异不显著外，与其他各处理差异均显著（P<0.05）；在燕麦成熟期（9月29日），燕麦单播处理干物质产量（1 766.7 g·m^-2）最高。在燕麦蜡熟期（9月29日），混播较燕麦单播处理燕麦株高提高了12.7%~28.3%、分蘖数增加了1~2个；与之相反，混播使箭筈豌豆株高降低、分枝数减少。鉴于研究区人工草地多用于制备青干草的利用方式，饲草应兼具产量和品质的优势，我们推荐燕麦与箭筈豌豆以2：1的混作方式进行种植，并于燕麦乳熟期进行收获。

关键词: 混播, 生物量, 株高, 分蘖/分枝