1. Isolation and evaluation of endophytic Streptomyces endus OsiSh-2 with potential application for biocontrol of rice blast disease.
- Author
-
Xu, Ting, Li, Yan, Zeng, Xiadong, Yang, Xiaolu, Yang, Yuanzhu, Yuan, Shanshan, Hu, Xiaochun, Zeng, Jiarui, Wang, Zhenzhen, Liu, Qian, Liu, Yuqing, Liao, Hongdong, Tong, Chunyi, Liu, Xuanming, and Zhu, Yonghua
- Subjects
PHYSIOLOGICAL control systems ,RICE blast disease ,SCANNING electron microscopy ,PROTEOLYTIC enzymes ,PATHOGENIC microorganisms ,ENDOPHYTES - Abstract
BACKGROUND Biocontrol is a promising strategy in the control of rice blast disease. In the present study, we isolated and characterized a novel antagonist to the pathogen Magnaporthe oryzae from rice endophytic actinomycetes. RESULTS Out of 482 endophytic actinomycetes isolated from rice blast infected and healthy rice, Streptomyces endus OsiSh-2 exhibited remarkable in vitro antagonistic activity. Scanning electron microscopy observations of M. oryzae treated by OsiSh-2 revealed significant morphological alterations in hyphae. In 2-year field tests, the spraying of OsiSh-2 spore solution (10
7 spores mL−1 ) is capable of reducing rice blast disease severity by 59.64%. In addition, a fermentation broth of OsiSh-2 and its cell-free filtrates could inhibit the growth of M. oryzae, suggesting the presence of active enzymes and secondary metabolites. OsiSh-2 tested positive for polyketide synthase-I and nonribosomal peptide synthetase genes and can produce cellulase, protease, gelatinase, siderophore, indole-3-acetic acid and 1-amino-cyclopropane-1-carboxylate deaminase. A preliminary separation indicated that the methanol extract of OsiSh-2 could suppress the growth of pathogens. The major active component was identified as nigericin. CONCLUSION Endophytic S. endus OsiSh-2 has potential as a biocontrol agent against rice blast in agriculture. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
- View/download PDF