草业学报2025，Vol.34Issue(5)：51-63,13.DOI:10.11686/cyxb2024229
紫云英生物固氮对土壤肥力及根瘤菌的响应特征
Response of biological nitrogen fixation by milk vetch to soil fertility and rhizobium inoculation
摘要
Abstract
Milk vetch(Astragalus sinicus)is one of the most important leguminous green manure crop in China,and high-efficiency biological nitrogen fixation is its key feature.Suitable environmental conditions and rhizobial inoculation can enhance the nitrogen-fixing ability of milk vetch.In this study,we selected three widely used cultivars of milk vetch,Yijiangzi,Xiangzi No.1,and Minzi No.7,and conducted pot trials using 15N-isotope tracing technology to investigate the effects and mechanisms of biological nitrogen fixation after inoculation with rhizobia(strain 7563R)under two soil fertility conditions.The results showed that,under high fertility conditions,the average biomass,nitrogen uptake,and biological nitrogen fixation of milk vetch were increased by 77.5%,52.6%,and 22.0%,respectively,compared with their values under low fertility conditions.However,the average nitrogen fixation efficiency of milk vetch under high fertility conditions was 44.7%,which was 10.4%lower than that under low fertility conditions(55.1%).Compared with uninoculated milk vetch,the rhizobia-inoculated milk vetch showed higher average nitrogen uptake and nitrogen fixation efficiency(increased by 13.5%and 4.3%,respectively).There were no significant differences in biomass,nitrogen fixation efficiency,and nitrogen fixation among the different cultivars of milk vetch,but phosphorus and potassium uptake were higher in Yijiangzi than in Xiangzi No.1 and Minzi No.7.Random forest analysis indicated that soil available potassium,available phosphorus,and pH significantly influenced the nitrogen fixation of milk vetch,with contribution rates of 10.03%,9.38%,and 8.28%,respectively.In conclusion,our results show that there is a significant interactive effect of soil fertility and rhizobia on the biological nitrogen fixation of milk vetch.The inoculation of milk vetch with rhizobia and its cultivation in suitable soil environments are important measures to promote nitrogen fixation and increase nitrogen uptake.关键词
紫云英/土壤肥力/根瘤菌/互作效应/生物固氮Key words
milk vetch/soil fertility/rhizobia/interactive effect/biological nitrogen fixation引用本文复制引用
张磊,杜锦涛,范倩玉,李顺,高嵩涓,曹卫东..紫云英生物固氮对土壤肥力及根瘤菌的响应特征[J].草业学报,2025,34(5):51-63,13.基金项目
现代农业产业技术体系建设专项资金(绿肥,CARS-22)和国家重点研发计划(2021YFD1700200)资助. （绿肥,CARS-22）
