摘要
【目的】探寻蒙古黄芪内生菌的促生功能,挖掘优异微生物资源。【方法】采用前期从蒙古黄芪品系甘芪1号根中分离纯化的20株内生细菌菌株(B1~B20,GenBank序列收录号OM938262~OM938281)为研究对象,以纯培养液为对照(CK),利用Salkowski显色法对产吲哚乙酸(IAA)功能菌株鉴定,然后对优异菌株的培养条件进一步进行优化研究。【结果】甘芪1号根可培养内生细菌菌株,有12株菌株较CK有明显Salkowski显色反应,测量各菌株产IAA浓度依次为B16>B18>B10>B20>B8>B13>B11>B3>B4>B6>B1>B17,产IAA浓度范围为2.74~26.48 mg/L,平均10.10 mg/L,其中B16高稳产IAA(GenBank OM938262),平均产IAA浓度高达26.48 mg/L,极显著高于其他菌株产IAA的水平。培养条件优化显示,B16菌株培养最适温度为15~25℃,在浓度为0.1%~7%的NaCl培养基均能正常生长,最适NaCl浓度为1%,最适pH为7.0,最适碳、氮源分别为酵母提取物和蛋白胨。培养条件优化后B16增殖及IAA产能较优化前分别极显著提高28.6%和53.5%。【结论】蒙古黄芪根内生细菌中产IAA菌株比例较高,是优异豆科药用植物微生物资源宝库,且筛选到一株高稳产IAA菌株B16,经过培养条件优化可达到40.658 mg/L,是有较大的生态调控利用潜力的菌株。
【Objective】To explore the growth promoting capabilities of its endophytic bacteria and harness excel⁃lent microbial resources.【Method】We isolated and purified 20 endophytic bacterial strains(B1~B20,GenBank se⁃rial numbers OM938262~OM938281)from the roots of"Ganqi No.1".Using a pure culture medium as control(CK),we identified functional strains capable of producing indoleacetic acid(IAA)through salkowski chromogenic method.Subsequently,we optimised the culture conditions for the outstanding strains.【Result】The results showed that 12 strains of endophytic bacteria from the root of"Ganqi No.1"exhibited significant Salkowski color reactions compared to CK.Among them,strain B16 demonstrated the highest IAA production concentration,followed by B18>B10>B20>B8>B13>B11>B3>B4>B6>B1>B17,respectively.The IAA production con⁃centrations ranged from 2.74 to 26.48 mg/L,average 10.10 mg/L.Notably,strain B16(GenBank OM 938262)consistently produced IAA at a high concentration of 26.48 mg/L,significantly outperforming other strains.Optimiza⁃tion of culture conditions showed that strain B16 thrived in 0.1%~7%NaCl medium at temperatures ranging 15℃to 25℃,with the optimum NaCl concentration being 1%and the optimal pH level at 7.0.Yeast extract and peptone were identified as the optimal carbon and nitrogen sources respectively.Following optimization process,strain B16 ex⁃hibited a 28.6%increase in proliferation and a 53.5%enhancement in IAA production.【Conclusion】These findings highlight the prevalence of IAA⁃producing strain among the endophytic bacteria of Astragalus mongholicus root,un⁃derscoring their importance as a valuable resource for medicinal leguminous plants.Strain B16,in particular,emerged as a highly stable producer of IAA with its production reaching 40.658 mg/L post⁃culture condition optimization.This strain holds significant potential for ecological regulation and utilization.
作者
刘垒
郭凤霞
陈垣
周洋
李红玲
李琴
李国藩
王辉
LIU Lei;GUO Feng-xia;CHEN Yuan;ZHOU Yang;LI Hong-ling;LI Qin;LI Guo-fan;WANG Hui(College of Life Sciences and Technology,College of Agronomy/Gansu Provincial Key Lab of Aridland Crop Science,Gansu Provincial Engineering Research Centre for Medical Plant Cultivation and Breeding,Gansu Agricultural University,Lanzhou 730070,China;Tianjin Key Lab of Modern Chinese Medicine Resource Research Enterprise,Tianjin Tianshli Modern Chinese Medicine Resources Co.,Ltd,Tianjin 300410,China)
出处
《草原与草坪》
CAS
CSCD
2024年第2期145-154,共10页
Grassland and Turf
基金
2021年省级现代丝路寒旱中药材产业发展项目(2130122)
甘肃省特色优势农产品评价-陇西黄芪(TYNPZ2020-18)
甘肃省科技支撑计划(1204FKCA123)
甘肃省现代农业中药材产业体系首席专家(GARS-ZYC-1)
企业委托项目(XDZY-(2017-2018)115,2019620005000036-2022620005001507)
甘肃农业大学SRTP(202111018)和SIETP(202211026)。
关键词
蒙古黄芪
内生细菌
吲哚乙酸
菌株筛选
培养条件优化
Astragalus membranaceus var.mongholicus
endogenous bacteria
indole⁃3⁃acetic acid
strain screen⁃ing
culture conditions optimization
作者简介
刘垒(1996-),女,山东济阳人,硕士研究生。E-mail:15954909071@163.com;通信作者:郭凤霞。E-mail:guofx@gsau.edu.cn.com。
