مهار زیستی ویروس موزاییک توتون با استفاده از باکتری‌های القاکننده رشد در میزبان گوجه‌فرنگی

Various plant pathogens such as viruses always cause damage to tomato throughout the word. Tobacco mosaic virus (TMV) is considered as the most devastating virus which significantly reduces the tomato yield. Application of plant growth promoting bacteria (PGPR) has been regarded as the promising method to control plant viruses. Therefore, this investigation aimed to find the efficient combination of PGPR strains to control TMV in tomato. Bacterial suspension with the volume of 100 milliliter were prepared and the concentration adjusted to 108 colony forming unit per milliliter. Tomato seeds were cultivated in autoclaved peat mass and tomato seedling were drenched with suspensions of Pseudomonas fluorescens, P. putidae, and B. subitilis at three-leaf stage. Afterwards, seedlings were inoculated with TMV and were inspected for symptoms till six weeks post inoculation. Then, optical density (OD) were recorded in Indirect-ELISA using polyclonal antibody produced against TMV as virus titer in infected plants at 405 nanometers. The experiment conducted in completely randomized design with 10 treatments and six replicates in each treatment. Control treatments were applied as follows: negative ( without inoculation of TMV) and positive control (TMV inoculated). The data were statistically analyzed using SAS software. The results showed that application of the aforementioned bacterial isolates was associated with lower OD (0.08) than that of positive control (0.87) in inoculated tomato plants (p<0.05). Also, application of B. subitilis resulted in higher OD (0.45) compared to negative control (p<0.05). The results showed that a combination of PGPR has synergistic effect on reducing TMV titer in tomato compared to other combinations.