中国草地学报2025，Vol.47Issue(11)：95-103,9.DOI:10.16742/j.zgcdxb.20250028
紫花苜蓿根际解钾菌筛选及其促生效果研究
Identification of Potassium-Solubilizing Bacteria from Alfalfa Rhizosphere and Their Growth-Promoting Potential
摘要
Abstract
In order to explore potassium-solubilizing microbial resources and investigate their effects on alfalfa(Medicago sativa)growth,this study isolated and screened potassium-solubilizing bacteria(KSB)with strong potassium-solubilizing ability from the rhizosphere soil of alfalfa using selective media.The potassium-solubilizing,phosphate-solubilizing,and indole-3-acetic acid(IAA)-producing capabilities of these strains were measured,and their identities were confirmed via 16S rRNA gene sequencing.Subse-quently,pot experiments were conducted using the selected superior strains to validate their impact on alfalfa growth.The results demonstrated that 21 KSB strains were isolated and screened from the alfalfa rhizosphere,among which 10 exhibited potassium-solubilizing activity,with solubilized potassium levels ranging from 1.57 to 7.96 μg/mL and solubilization rates ranging from 12.07%to 57.50%.Five strains(jk6-5、jk20-1、jk20-2、jk20-3 and jk20-8)with high potassium-solubilizing activity also demonstrated IAA pro-duction and phosphate-solubilizing abilities.Their IAA secretion levels ranged from 9.60 to 11.77 μg/mL,while inorganic phosphate solubilization ranged from 2.84 to 173.96 μg/mL,and organic phosphate solubi-lization from 35.34 to 62.55 μg/mL.Based on 16S rRNA gene sequencing,strains jk20-8,jk20-1,and jk20-2 were identified as Pantoea ananatis,strain jk20-3 belonged to the Paenibacillus hordei group,and strain jk6-5 was identified as Priestia megaterium.Inoculation of the superior strains jk20-8,jk20-3,and jk6-5 into alfalfa significantly increased plant height,root length,aboveground biomass,underground bio-mass,and nitrogen(N),potassium(K),and phosphorus(P)contents in plants.Additionally,soil avail-able N,available P,available K,and organic matter contents were enhanced,with strain jk20-8 exhibiting the most pronounced growth-promoting effects.In conclusion,the potassium-solubilizing strain jk20-8 serves as a promising candidate for developing potassium-solubilizing microbial fertilizers.关键词
解钾菌/紫花苜蓿:促生特性/生物量/土壤养分Key words
Potassium-solubilizing bacteria/Alfalfa/Growth-promoting properties/Biomass/Soil nutrients分类
农业科技引用本文复制引用
张怡忻,姚拓,李雪梅,李昌宁,杨晓蕾,沙凤琴..紫花苜蓿根际解钾菌筛选及其促生效果研究[J].中国草地学报,2025,47(11):95-103,9.基金项目
草业生态系统教育部重点实验室揭榜挂帅项目(KLGE-2024-05) （KLGE-2024-05）
甘肃省教育厅:高校科研创新平台重点培育项目(2024CXPT-07) （2024CXPT-07）
