Induction of resistance and changes of phenol and peroxidase in tomato plants treated with Bacillus subtilis and salicylic acid against Fusarium wilt and root-knot diseases

In this paper, effects of Bacillus subtilis and salicylic acid on changes in biochemical and defense enzyme activity of tomato plant against two important pathogens Meloidogyne javanica and Fusarium oxysporum f.sp. lycopersici, was evaluated. A greenhouse experiment was designed in order to assess the effect of salicylic acid and B. subtilisin the induction of resistance markers, including peroxidase andtotal phenol content. B. subtilis was used as live stimulator at concentration 109 CFU/ml and salicylic acid as a chemical inducer at concentration 5mμ before treatment with pathogens. The results showed that application of salicylic acid and B. subtilis in combination and also when applied singly, effectively increased peroxidase activity and total phenol compared to treatments of Fusarium (F), nematode (M) and control (C). The activity of peroxidase and the phenol content of the plant reach to its highest level at the fifth and seventh day after inoculation with the pathogens, respectively. It is suggested to further investigate the use of bacillus and SA in different combinations as a safe and effective method to control this complex disease.