Efficiency of Bacillus subtilis in the control of septoria leaf spot and bacterial spot in tomato

Two experiments were carried out to evaluate the effect of different doses of the product based on B. subtilis for the control of Septoria lead spot and bacterial spot in the tomato crop. The experiments were developed in the period of February – November 2018 in the field of horticultural production and in two different laboratories in the National University of Asuncion (UNA). The first one was the Plant Protection laboratory in the Faculty of Agricultural Sciences (FCA) and the second, the laboratory of Histology in the Faculty of Veterinarian Sciences (FCV). The following variables were evaluated in Experiment I: the severity and damage intensity (DI) of the Septoria leaf spot and the Bacterial Spot and the fruit yield and soluble solids. In Experiment II: number of colonies of B. subtilis in PDA media and endophytic colonization in the plant were determined. The design was completely randomized with five treatments and six repetitions. The results were subjected to ANOVA and the Tukey test with a 5% probability of error. The product reduced the severity of Septoria leaf spot and bacterial spot, as well as a low DI of Septoria and Bacterial spot. Also, the product improves the quality of fruits increasing the yield and the content of soluble solids. No endophytic colonization of B. subtilis was observed in plants evaluated at 24, 48, 72 and 96 h after inoculation.