Upadhyay Sudhir K, Singh Devendra P, Saikia Ratul
Department of Environmental Sciences, B.B. Ambedkar University, Vidya Vihar, Rai Bareilly Road, Lucknow, Uttar Pradesh, 226 025, India.
Curr Microbiol. 2009 Nov;59(5):489-96. doi: 10.1007/s00284-009-9464-1. Epub 2009 Aug 22.
In this study, a total of 130 rhizobacteria was isolated from a saline infested zone of wheat rhizosphere, and screened for plant growth promoting (PGP) traits at higher salt (NaCl) concentrations (2, 4, 6, and 8%). The results revealed that 24 rhizobacterial isolates were tolerant at 8% NaCl. Although all the 24 salt tolerable isolates produced indole-3-acetic acid (IAA), while 10 isolates solubilized phosphorus, eight produced siderophore, and six produced gibberellin. However, only three isolates showed the production of 1-aminocyclopropane-1-carboxylate (ACC) deaminase. Diversity was analyzed through 16S rDNA-RFLP, and of these isolates with three tetra cutter restriction enzymes (HaeIII, AluI, and MspI), the representative cluster groups were identified by 16S rDNA sequencing. Bacillus and Bacillus-derived genera were dominant which showed PGP attributes at 8% NaCl concentration. Out of 24 isolates, nitrogen fixing ability (nif H gene) was detected in the two isolates, SU18 (Arthrobacter sp.) and SU48.
在本研究中，从受盐害影响的小麦根际区域共分离出130株根际细菌，并在较高盐（NaCl）浓度（2%、4%、6%和8%）下筛选其促进植物生长（PGP）的特性。结果显示，24株根际细菌分离株在8% NaCl浓度下具有耐受性。虽然所有24株耐盐分离株均产生吲哚-3-乙酸（IAA），但有10株分离株能溶解磷，8株产生铁载体，6株产生赤霉素。然而，只有3株分离株显示出产生1-氨基环丙烷-1-羧酸（ACC）脱氨酶的能力。通过16S rDNA-RFLP分析多样性，并用三种四碱基切割限制酶（HaeIII、AluI和MspI）对这些分离株进行分析，通过16S rDNA测序鉴定代表性聚类组。芽孢杆菌属和芽孢杆菌衍生属占主导地位，它们在8% NaCl浓度下表现出PGP属性。在24株分离株中，在两株分离株SU18（节杆菌属）和SU48中检测到固氮能力（nif H基因）。
