Effect of Bacillus methylotrophicus on control of Fusarium oxysporum f.sp. melonis and expression of some defense-related genes in melon plant

In this study, we investigated the effect of Bacillus methylotrophicus on control of Fusarium wilt disease of melon caused by F. oxysporum f. sp. melonis and the expression of some defense-related genes in melon. This experiment was carried out using two methods of soil treatment and seed treatment with B. methylotrophicus under greenhouse conditions. Furthermore, the expression of galactinol synthase 2 (GAL2), β-1,3- glucanas 2 (βGlu2), catalase (CAT) and chitinase (Chi) was evaluated by real-time PCR (qRT-PCR) technique. Disease severity was significantly reduced in plants treated with B. methylotrophicus particularly in soil treatment method. The expression of GAL2, βGlu2, CAT and Chi genes was significantly increased by B. methylotrophicus. The results showed the biocontrol activity of B. methylotrophicus against F. o. f. sp. melonis and the subsequent increase in the expression of defense-related genes in melon plant. Furthermore, our results suggest that B. methylotrophicus enhances disease resistance in melon against F. o. f. sp. melonis probably through induction of defense-related genes.