Inactivation of Tobacco mosaic virus in soil by Pseudomonas putida A3-m strain to prevent virus mosaic disease

Previous studies showed that Pseudomonas putida A3-m exhibited a strong antiviral activity against Tobacco mosaic virus (TMV) in tobacco. However, its potential effect on the amount of TMV in the soil remains unknown. In this study, all plants in two treatments and the control did not have significant differences in terms of height and fresh weight at 20 and 30 days after transplanting. And the effect of A3-m on soil TMV community in tobacco rhizosphere was investigated through real-time reverse transcriptase-polymerase chain reaction. The results showed that the amount of TMV in the A3-m treated soil initially decreased significantly compared with the control whose amount maintained at certain levels. The severity rate of TMV disease was significantly lower in P. putida A3-m treatment before the seedlings were transplanted (referred to as the early treatment) compared with that in P. putida A3-m treatment after the seedlings were transplanted (referred to as the late treatment) and in the control. These data show that the early treatment of the soil benefit for protecting the plants against TMV infection. Thus, P. putida A3-m can be utilized as a biological control for plant protection against viral pathogens through the inactivation of TMV in the soil.