Abstract: Allelopathic effects of the dominant plant Artemisia gmelinii on the Loess Plaetau on the four common legume forage (Onobrychis viciaefolia,Astragalus adsurgens,Lotusc corniculatus and Medicago sativa) were explored by studying the effects of A. gmelini extracts at different concentrations on seed germination and physiological characteristics of seedling growth. The results demonstrated that,the germination rate and germination power of these legume species generally showed the trend of "promotion at lower concentration,but inhibition at higher concentration";the comprehensive allelopathic effects on M. sativa were inhibition in different treatments and the inhibitory effect was gradually enhanced with the increase of litter content of A. gmelinii. However,the comprehensive allelopathic effects on O. viciaefolia,A. adsurgens and L. corniculatus showed the trend of "promotion at low concentration,but inhibition at high concentration",and the promoting effects on O. viciaefolia and A. adsurgens were the strongest at 30 g litter concentration of A.gmelinii while for L.corniculatus the strongest promoting effect was at 60 g litter concentration of A.gmelinii. All these results preliminarily indicated that the A. gmelinii dominated grassland is not suitable for planting and reseeding M. sativa. Grassland with the right amount of A. gmelinii is beneficial for planting and reseeding O. viciaefolia,A. adsurgens and L. corniculatus.

Key words: Artemisia gmelinii, Allelopathy, Legume forage, Reseeding

摘要： 研究了黄土区优势植物铁杆蒿（Artemisia gmelinii）枯落物对红豆草（Onobrychis viciaefolia）、沙打旺（Astragalus adsurgens）、百脉根（Lotusc corniculatus）和紫花苜蓿（Medicago sativa）等四种常见豆科牧草种子萌发和幼苗生理特性的化感效应。结果表明：铁杆蒿对这几种豆科牧草的发芽率和发芽势总体上均呈现“低质量浓度促进，高质量浓度抑制”的效应；紫花苜蓿综合化感效应在不同处理中均受到抑制，随着铁杆蒿枯落物含量的增加，抑制作用增强；但红豆草、百脉根和沙打旺的综合化感效应表现出低促高抑的趋势；红豆草和沙打旺在30 g铁杆蒿枯落物浓度时促进效应最强，百脉根在60 g时促进效应最强。以上结果初步表明在有铁杆蒿分布的草地不适合种植以及补播紫花苜蓿，而适当密度的铁杆蒿分布有助于种植以及补播红豆草、百脉根和沙打旺。

关键词: 铁杆蒿, 化感作用, 豆科牧草, 补播