土壤微生物多样性对豆-禾牧草混播的响应及其与牧草产量和品质的关系

At present, many artificial grasslands in our country are mostly single herbage varieties, and long-term planting not only reduces the quality of forage, but also causes the serious occurrence of herbage pests and diseases seriously affecting forage production. Legume-grass mixtures can play a complementary effect between forage grass, raise the forage yield and quality, are advantageous to the forage processing and modulation, improve the quality and endurance of the grassland, increase content of nitrogen and organic matter in the soil to keep nitrogen nutrition balance in grassland ecosystem. So, It is of great significance to study the application and mechanism of legume-grass mixtures in artificial grassland ecosystem. Based on the artificial grassland production status, this project study the response mechanism of herbage rhizosphere microbes (fungi, bacteria, and carbon and nitrogen functional microbes) ecological function diversity, community structure and community abundance on perennial white clover and orchardgrass mixtures in the artificial grassland using molecular biology techniques, explore the temporal variation of microbes diversity in artificial grassland and relationships with herbage yield and quality factors in legume-grass mixtures. By conducting the experiments, we can clarify the mechanism of soil microorganism on high efficiency production of white clover and orchardgrass mixtures to provides the theory basis on ecological, efficient and sustainable forage production system.

目前我国很多人工栽培草地大多是单一的牧草品种，长期种植不仅使牧草的品质下降，也造成了牧草病虫害的严重发生严重影响其产量。豆-禾牧草混播可以有效的发挥牧草间的互补效应，提高牧草产量和品质，有利于加工调制，改善草地质量和增强草地持久力，增加土壤中的氮素养分和有机质含量，维持草地生态系统氮素营养平衡，因此研究豆-禾牧草混播在人工草地生态系统中的运用及其作用机理具有重要意义。本项目立足于人工草地生产现状，系统研究人工草地生态系统牧草根际土壤微生物（真菌、细菌和碳氮功能微生物）生态功能多样性、群落结构组成和群落的丰度对多年生白三叶和鸭茅混播模式响应机制，探索豆-禾牧草混播模式下人工草地土壤微生物多样性的变化规律及其牧草的产量和品质构成因素之间的关系，明确白三叶和鸭茅混播高效生产的土壤微生物作用机理，为构建生态、高效、可持续的牧草生产体系提供理论依据。

目前我国很多人工栽培草地大多是单一的牧草品种，长期种植不仅使牧草的品质下降，也造成了牧草病虫害的严重发生严重影响其产量。豆-禾牧草混播可以有效的发挥牧草间的互补效应，提高牧草产量和品质，有利于加工调制，改善草地质量和增强草地持久力，增加土壤中的氮素养分和有机质含量，维持草地生态系统氮素营养平衡，因此研究豆-禾牧草混播在人工草地生态系统中的运用及其作用机理具有重要意义。研究表明2019和2020年年均产量表现为混播鲜重和干重接近于鸭茅的产量。混播的粗蛋白、粗脂肪和粗纤维含量具有鸭茅和白三叶单播之间。从微生物种群结构来看，混播提升了土壤微生物多样性，尤其是固氮微生物，这可能导致土壤的脲酶等土壤酶的活性提高，进一步提升了土壤可利用氮含量。