Abstract
Strain TJB-8 has been isolated from the root soil of poplar and has exhibited a strong inhibitory effect against Cytospora chrysosperma, a predominant fungus causing poplar canker. In order to provide technical guidance for further exploitation and utilization of TJB-8, the species of TJB-8 and its antifungal substances were investigated in this study. The strain TJB-8 was identified based on morphological and physiological characteristics, as well as a phylogenetic analysis of partial 16S rDNA sequence; the antifungal substances of TJB-8 were analyzed by colony diameter assay and two-compartment plate method. Results revealed that sterile culture filtrates of TJB-8 had a strong antifungal activity against C. chrysosperma with an inhibitory rate of 97.42% (over 72 h). The hyphae of C. chrysosperma at the edge of the colony exhibited swelling after being treated with a sterile culture filtrate. Also, this sterile culture filtrate effectively inhibited the hyphae growth of Colletotrichum gloeosporioides, Alternaria tenuissima, Fusarium oxysporum, Fusarium graminearum, and Rhizoctonia solani. Strain TJB-8 was identified as Bacillus cereus and produced β-1, 3-glucanase and protease. Moreover, TJB-8 produced high antifungal activities against C. chrysosperma with crude proteins (100% in 72 h), lipopeptides (100% in 72 h), and volatiles (76.08% in 48 h). Thus, B. cereus TJB-8 was an antagonistic bacterium with strong antifungal activity, a wide inhibitory spectrum, and varied antifungal substances, having a broad prospect of industrial development and field application as a biological fungicide.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call