草业学报2025，Vol.34Issue(3)：144-153,10.DOI:10.11686/cyxb2024170
4株红砂根际固氮菌分离鉴定及对幼苗促生作用的研究
Isolation and identification of four strains of Reaumuria soongorica root zone nitrogen fixing bacteria and their role in seedling growth promotion
摘要
Abstract
The aim of this research was to isolate nitrogen fixing bacteria in the root zone soil of desert plants,investigate their effects on nitrogen metabolism of Reaumuria soongorica seedlings,and verify the growth-promoting effect of the isolated nitrogen fixing bacteria.In this study,four strains of nitrogen fixing bacteria were isolated from the root zone soil of R.soongorica by the dilution-coated plate method,using Ashby's solid medium.The taxonomic status and growth-promoting characteristics of the strains were identified by morphological,physiological and biochemical characteristics as well as by 16S rDNA sequence analysis.The results showed that strains designated Y3 and Y2 were Bacillus sp.,strain P4 was Enterobacter mori,and strain N12 was Enterobacter cloacae.Inoculation with the four strains of nitrogen fixing bacteria increased the activities of nitrate reductase(NR),glutamine synthetase(GS),and glutamate synthetase(GOGAT)in the leaves and roots of the R.soongorica seedlings.There were also differences in the root length and relative water content of leaves,and above-ground and below-ground fresh weight of R.soongorica seedlings after inoculation with the isolated bacterial strains(P<0.05);among them,the nitrogen fixing bacterium P4 had the most significant growth-promoting effect,with the NR activity in leaves and roots increased by 31.9% and 34.6%,respectively(P<0.05),the GOGAT activity by 25.6% and 25.1%,respectively(P<0.05),and the GS activity by 23.3% and 24.3%,respectively(P<0.05).Furthermore,root length,leaf relative water content,above-ground and below-ground fresh weight were increased(P<0.05),respectively,by 27.9%,20.7%,33.3% and 33.2% .In conclusion,the four strains of nitrogen fixing bacteria exhibited ability to promote the growth and development of R.soongorica seedlings and improve their survival rate.The isolated strains represent high-quality resources for the development of microbial plant growth promoting agents.关键词
固氮菌/分离鉴定/促生作用/氮代谢/红砂Key words
nitrogen fixing bacteria/bacterial isolation and identification/plant-growth-promoting/nitrogen metabolism/Reaumuria soongorica引用本文复制引用
张峰,种培芳,包新光,王雪莹..4株红砂根际固氮菌分离鉴定及对幼苗促生作用的研究[J].草业学报,2025,34(3):144-153,10.基金项目
国家自然基金:荒漠植物红砂根际促生细菌筛选及其抗逆性研究(32160407),甘肃省重点研发项目:典型荒漠灌木根际微生物固碳及高效菌肥资源挖掘与利用(23YFFA0065)和草业生态系统教育部重点实验室开放课题:荒漠草原植物红砂耐盐促生菌的分离筛选、鉴定及其促生效果研究(KLGE202215)项目资助. （32160407）
