ANTIFUNGAL ACTIVITY OF Bacillus amyloliquefaciens HGG10 ISOLATED FROM BANANA RHIZOSPHERE AGAINST Fusarium sambucinum FG2 CAUSING CROWN ROT IN BANANA

Abstract

Crown rot of banana caused by Fusarium species is among the most prevalent postharvest diseases, leading to significant losses in both yield and fruit quality. This study aimed to evaluate the in vitro antifungal activity of bacteria isolated from the banana rhizosphere against Fusarium sambucinum FG2, the pathogen responsible for banana crown rot. Out of 92 bacterial isolates, 25 exhibited antagonistic activity against Fusarium sambucinum FG2 in dual culture assays, with inhibition rates ranging from 28.2% to 60.3%. The most effective strain, designated HGG10, was identified as Bacillus amyloliquefaciens. Strain HGG10 was capable of producing fungal cell wall-degrading enzymes (β-1,3-glucanase, chitinase and protease) and siderophores involved in iron competition. Genetic analysis revealed the presence of biosynthetic genes for antifungal lipopeptides including bacillomycin, fengycin and surfactin. Both volatile organic compounds (VOCs) and cell-free culture supernatants from strain HGG10 showed strong inhibitory effects on Fusariium sambucinum FG2. These results suggest that Bacillus amyloliquefaciens HGG10 is a promising biocontrol agent for the prevention and management of banana crown rot.