Ngày nhận bài: 15-08-2020 / Ngày duyệt đăng: 25-12-2023
Developing new biofertilizers has been an area of great interest in modern agriculture. This study focused on actinobacteria possessing high chitinase activity, biofilm formation, plant growth promotion, and antifungal activity. Two chitinolytic actinomyces strains, YSS-3.3 and YWS-5.1, were isolated from soil and chitin flake samples collected from Yok Don National Park in the Central Highlands, Vietnam. These strains exhibited high specific activities of chitinases and formed biofilms. 16S rRNA gene analysis revealed that both strains had the closest evolutionary relationship to Luteimicrobium albumwith 99.41% sequence similarity and 100% query cover. Plate assays showed that the actinomyces had cellulolytic and amylolytic activities; insoluble zinc, potassium, and phosphate solubilization; and produced siderophores. UV-HPLC analysis revealed that the bacteria secreted phytohormones (IAA, GA3, and zeatin) into their cultures. Dual culture assay indicated that the bacteria possessed antifungal activity against Fusarium oxysporum. These analyses indicated that the isolated actinomyces are good candidates for further studies concerning crop production. These strainsare also potent resources for further research on their genome sequences and systems of chitinases, cellulases, and amylases.
