植物次级代谢物及其降解产物对包括牧草在内的所有农业生态系统都有重要影响。生化它感影响耕作制度和一物种进入另一已建植物种的草场。自体毒性和异体毒性都是生化它感的类型。苜蓿是既具自毒又具它毒的物种,收后立即重播苜蓿常因自毒而生长不良。还有几种牧草也具自体毒性,许多牧草则表现与杂草间的异体毒性。业已鉴别出一些起生化它感作用的生化它感物质。这类物质的鉴别有助于培育出抗性的牧草品种和维持其生产力。轮作、作物覆盖、间作、双季作、免耕、非轮作均涉及到生化它感。某些牧草对生化它感物具有一定抗性,可以用作抗性种质。一些牧草和杂草对苜蓿有生化它感效应;而苜蓿对某些杂草有生化它感效应。这可以启示苜蓿生产中的除草剂的研究。 Plant secondary metabolites and their degradation products have a major impact on all agro-ecosystems, including pasture. It affects the farming system and the pastures where one species enters another planted species. Both autotoxicity and allogenic toxicity are types of biochemical sensations. Medicago sativa is both self-toxic and has its poisonous species, replanting alfalfa immediately after receipt often due to self-toxicity and poor growth. Several forages are also autotoxic and many forages exhibit allogeneic toxicity to weeds. A few biochemical and affective substances that have a role in biochemistry have been identified. The identification of such substances helps to breed and maintain resistant forage species. Crop rotation, crop cover, intercropping, double cropping, no tillage and non-rotation all involve biochemistry. Some forages have some resistance to biochemistry and may be used as resistant germplasm. Some forages and weeds have a medicinal effect on alfalfa; alfalfa, on the other hand, has a biochemical effect on some weeds. This can shed light on the study of herbicides in alfalfa production.