Muangham Supattra, Pathom-Aree Wasu, Duangmal Kannika
a Department of Microbiology, Faculty of Science, Kasetsart University, Chatuchak, Bangkok 10900, Thailand.
Can J Microbiol. 2015 Feb;61(2):164-70. doi: 10.1139/cjm-2014-0645. Epub 2014 Nov 21.
A total of 210 melanogenic actinomycetes were isolated from 75 rhizospheric soils using ISP6 and ISP7 agar supplemented with antifungal and antibacterial agents. Their morphological characteristics and the presence of ll-diaminopimelic acid in whole-cell hydrolyzates revealed that all isolates belonged to the genus Streptomyces. Their ability to inhibit the growth of 2 pathogenic rice bacteria, Xanthomonas oryzae pv. oryzae and Xanthomonas oryzae pv. oryzicola, was observed using the agar overlay method. The results indicated that 61.9% of the isolates could inhibit at least one of the tested rice pathogens. Among these, isolate TY68-3 showed the highest antibacterial activity and siderophore production. The 16S rRNA gene sequence analysis of 46 representative isolates revealed that isolates with high similarity to Streptomyces bungoensis were frequently found. The present study indicated the potential of melanogenic actinomycetes for use as biocontrol agents against X. oryzae as well as their diversity in rhizospheric soils.
使用添加了抗真菌和抗菌剂的ISP6和ISP7琼脂，从75份根际土壤中总共分离出210株产黑色素放线菌。它们的形态特征以及全细胞水解物中ll-二氨基庚二酸的存在表明，所有分离株均属于链霉菌属。使用琼脂覆盖法观察了它们抑制两种致病性水稻细菌——水稻白叶枯病菌和水稻条斑病菌生长的能力。结果表明，61.9%的分离株能够抑制至少一种受试水稻病原菌。其中，分离株TY68-3表现出最高的抗菌活性和铁载体产生能力。对46株代表性分离株的16S rRNA基因序列分析表明，经常发现与邦戈链霉菌高度相似的分离株。本研究表明产黑色素放线菌作为水稻白叶枯病菌生物防治剂的潜力以及它们在根际土壤中的多样性。
