National Bureau of Agriculturally Important Microorganisms, Kusmaur, Mau 275101, Uttar Pradesh, India.
Curr Microbiol. 2012 Sep;65(3):330-6. doi: 10.1007/s00284-012-0160-1. Epub 2012 Jun 10.
Four antagonists bacteria namely, Bacillus megaterium MB3, B. subtilis MB14, B. subtilis MB99 and B. amyloliquefaciens MB101 were able to produce chitinase, β-1,3-glucanase and protease in different range with the presence of Rhizoctonia solani cell wall as a carbon source. Amplification of chitinase (chiA) gene of 270 bp and β-1, 3-glucanase gene of 415 bp was given supportive evidence at molecular level of antibiosis. After in vitro screening, all antagonists were tested against R. solani under greenhouse conditions. Root treatment of Bacillus strains showed superior defense during pathogen suppression in terms of chitinase, glucanase, peroxidase, poly phenol oxidase, phenylalanine ammonia-lyase activity and total phenolic content in leaves of tomato. All these enzymes accumulated high in tomato leaves as compared to roots. Pathogenesis-related proteins and defense-related enzymes accumulation was directly correlated with plant protection and greenhouse results indicated that B. amyloliquefaciens MB101- and B. subtilis MB14-treated plants offered 69.76 and 61.51 % disease reductions, respectively, over the infected control. These results established that these organisms have the potential to act as biocontrol agents. This study could be highlighted a mutual importance of liquid formulation of antagonistic Bacillus spp. against root associated sclerotia former pathogen R. solani.
四种拮抗细菌，即巨大芽孢杆菌 MB3、枯草芽孢杆菌 MB14、枯草芽孢杆菌 MB99 和解淀粉芽孢杆菌 MB101，能够在含有茄病镰刀菌细胞壁作为碳源的情况下产生不同范围的几丁质酶、β-1,3-葡聚糖酶和蛋白酶。在分子水平上，几丁质酶（chiA）基因 270bp 和β-1,3-葡聚糖酶基因 415bp 的扩增为抑菌作用提供了支持证据。经过体外筛选，所有的拮抗剂都在温室条件下对茄病镰刀菌进行了测试。枯草芽孢杆菌菌株的根部处理在抑制病原体方面表现出了更好的防御效果，表现在几丁质酶、葡聚糖酶、过氧化物酶、多酚氧化酶、苯丙氨酸解氨酶活性和番茄叶片总酚含量方面。与根部相比，这些酶在番茄叶片中积累量更高。病程相关蛋白和防御相关酶的积累与植物保护直接相关，温室结果表明，解淀粉芽孢杆菌 MB101 和枯草芽孢杆菌 MB14 处理的植物分别减少了 69.76%和 61.51%的病害。这些结果表明这些生物有作为生物防治剂的潜力。本研究强调了液体剂型拮抗芽孢杆菌对与根相关的菌核形成病原菌茄病镰刀菌的重要性。
