Abstract: In order to explore the allelopathy of herbicide stress on three forages. In this laboratory bioassay study, the seedlings of alfalfa (Medicago sativa), ryegrass (Lolium perenne) and sainfoin(Onobrychis viciaefolia) were treated with different recommended dosages of glufosinate and glyphosate, respectively. To determine the effects of three forage extracts on the seed germination and seedling growth of the recipient Brassica chinensis, the allelopathy of forage was analyzed by combining allelopathy effect value, which was aimed at providing theoretical reference for weed control and scientific use of herbicides in forage field. The results showed that the three forage extracts had certain effects on the germination rate, germination potential, germination index, seedling height, maximum root length and vigor index of the recipient plants, and the maximum root length had the greatest effect, the allelopathic effects of the two herbicides were significantly stronger than that of the control, especially after glyphosate stress. The order of allelopathic effects on the tested forages was as follows:sainfoin > alfalfa > ryegrass. In conclusion, herbicide stress can significantly enhance the allelogenicity of alfalfa, sainfoin and ryegrass.

Key words: Herbicide stress, Aqueous extracts, Allelopathy, Seed germination, Seedling growth

摘要： 为探明除草剂胁迫对3种牧草的化感作用，本研究采用室内生测法，采用不同推荐剂量的草铵膦和草甘膦分别处理紫花苜蓿（Medicago sativa）、黑麦草（Lolium perenne）和红豆草（Onobrychis viciaefolia）幼苗，测定3种牧草浸提液对受体小白菜（Brassica chinensis）种子萌发和幼苗生长的影响，并结合化感效应值对牧草的化感活性进行分析，旨在为牧草田的杂草防治及科学使用除草剂提供理论参考。结果表明：3种牧草浸提液对受体植物发芽率、发芽势、发芽指数、苗高、最大根长及活力指数均具有一定的影响，对最大根长的影响最大；受2种除草剂胁迫后，供试牧草的化感作用均显著高于清水处理，其中草甘膦胁迫后的表现更为明显，其对供试牧草化感作用的强弱顺序为：红豆草>紫花苜蓿>黑麦草。综上，除草剂胁迫下可明显增强紫花苜蓿、红豆草和黑麦草的化感作用。

关键词: 除草剂胁迫, 牧草浸提液, 化感作用, 种子萌发, 幼苗生长