Groundnut, Arachis hypogaea L., crop is an important oil seed crop in India and is prone to attack by numerous fungal and viral diseases, among the soil-borne diseases, stem rot caused by Sclerotium rolfsii Sacc. is economically important. Incidence (86.6%) of the stem rot disease was recorded in Coimbatore district, Tamil Nadu, India, during the roving survey. For its management, an attempt was made to isolate bacterial endophyte from peanut seeds of different groundnut cultivars by culture-dependent analysis. Totally, 16 bacterial endophytes (endophytes groundnut (EGN) 1 to EGN 16 along with standards TNAU-Pf1 and EPC 5) were obtained and characterized through morphological, biochemical and molecular studies and also phytostimulation activities were performed. Among the isolates, EGN 1 and EGN 4 showed positive results for indole acetic acid (IAA), siderophore, phosphate solubilization and protease tests in vitro. The dual culture analysis showed inhibition rates of 60.1% (dual plate assay), 68.23% (filter paper disc assay) and 100% (triangle method of streaking and culture filtrate assay) for EGN 1 against S. rolfsii. Further, the crude metabolite assay showed 97.7% inhibition in EGN 1, followed by 87.7% in EGN 4. The roll towel study showed a high vigour index of 4286.7 in EGN 1; hence, this isolate was chosen. Further, thin-layer chromatography (TLC) analysis showed various bands at 0.72 Rf, whereas GC-MS analysis indicated the prominent peaks of hexadecanoic acid and cis-vaccenic acid that may responsible for antifungal activity. In a molecular approach, the genomic DNA of EGN 1 strain was used to amplify a 1200 bp PCR-fragment and sequenced. The overall outcome of this study showed that Pseudomonas spp. EGN 1 had a great potential as a bio-stimulant and biocontrol agent to manage effectively the stem rot in peanut.

中文翻译：

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种子细菌内生菌假单胞菌属物种的文化依赖性分析。EGN 1对抗花生中的茎腐病（Sclerotium rolfsii Sacc。）

花生，花生，花生，是印度重要的油料作物，在土壤传播的疾病中，很容易受到真菌和病毒性疾病的侵袭，其中包括土壤传播的疾病，即由菌核病引起的茎腐病。在经济上很重要。在巡回调查中，印度泰米尔纳德邦的哥印拜陀区记录了茎腐病的发病率（86.6％）。为了对其进行管理，尝试通过培养依赖性分析从不同花生品种的花生种子中分离细菌内生菌。总共获得了16种细菌内生菌（花生内生菌（EGN）1至EGN 16以及标准TNAU-Pf1和EPC 5），并通过形态，生化和分子研究对其进行了表征，并进行了植物刺激活性。在分离株中 EGN 1和EGN 4在体外吲哚乙酸（IAA），铁载体，磷酸盐增溶和蛋白酶测试中均显示阳性结果。双重培养分析显示，对S. rolfsii的EGN 1的抑制率分别为60.1％（双板测定），68.23％（滤纸圆盘测定）和100％（三角划线和培养滤液测定）。此外，粗代谢物测定在EGN 1中显示97.7％的抑制，然后在EGN 4中显示87.7％。因此，选择了该隔离株。此外，薄层色谱（TLC）分析显示在0.72 Rf处有多个谱带，而GC-MS分析表明十六烷酸和顺式-庚酸的突出峰可能负责抗真菌活性。在分子方法中 EGN 1菌株的基因组DNA用于扩增1200 bp PCR片段并测序。这项研究的总体结果表明，假单胞菌属。EGN 1作为生物刺激剂和生物防治剂，具有有效管理花生茎腐病的巨大潜力。