Using of auxin signaling pathway to investigate the contrast between two different strains of Bacillus against Agrobacterium

Crown gall is one of the most damaging bacterial diseases caused economic damages. Nowadays special attention has been focused on biological control of plant diseases as an alternative to chemical control in terms of the dangers of pesticides. There was no special research focused on the interaction between Bacillus and Agrobacterium until now. The objective of this study was understanding molecular mechanisms between B. subtilis as a biocontrol agent and A. tumefaciens. This information would provide us the opportunity for better management of the disease. In this study tobacco plants (Nicotiana tabacum), IBRC–M10701strains of A. tumefaciens, B. subtilis strain ATCC21332, and Bacillus subtilis OKB105 strain FKR3 were used. miRNAs have an important effect in the auxin signaling pathway and resistance induction. The expression level of two miRNAs, miR167 and miR393 was measured using Real–Time PCR; 1, 3 and 6 days after inoculations of A. tumifaciens and B. subtilis revealed significant differences with the control plants. The results of expression levels demonstrated FKR3 showed a better effect to ATCC21332 in controlling A. tumifaciens. Research showed a positive effect of Bacillus on Agrobacterium. This study indicates the possible use of biological controls such as B. subtillis in controlling of A. tumefaciens.