| Spraying banana leave axil with Bacillus subtilis strain TR21 could induce banana roots enhancing the resistance to Fusarium oxysporum f. sp. cubense. In order to discover the relationship between induced resistance by TR21 and accumulation of phenolic compounds and lignin, two susceptible banana cultivars, dwarf banana Musa spp. ABB cv. Guangfen No.1 and Cavendish banana Musa spp. AAA cv. Brazil, were chosen as research materials. Root inoculation with F. oxysporum f. sp.cubense race 4 strain Foc009 were handled as a positive control, seedlings treated with water as a negative control. The root total soluble phenolic acids (RTSPA), cell wall bound phenolic acids (CWBPA), lignin content of seedling roots were tested after treated at 0 h, 12 h, 24 h, 36 h, 48 h, 60 h and 72 h.The results showed that followed time expansion, RTSPA, CWBPA and lignin content increased, at and after 48 h, RTSPA, CWBPA and lignin contents in Foc009 and TR21 treatments were significantly higher than water control in different banana cultivars. Except for RTSPA in Guangfen No.1, the RTSPA, CWBPA and lignin contents of Foc009 treatments were significantly higher than TR21 treatments in two susceptible cultivars. It was concluded that spraying leave axil by TR21 could induced the susceptible banana cultivars accumulating phenolic compounds and lignin on roots, and this were similar with the action induced by F. oxysporum, but the level
induced by TR21 were lower than pathogen. |
