Effect of Endophytic Bacteria Bacillus subtilis on the Components of Pro-/Antioxidant System of Tomato (Solanum lycopersicum L.) Plants Infected with Potato Viruses X and Y

In this work, the ability of endophytic bacteria Bacillus subtilis (Cohn.) (strains 26D and Ttl2) to suppress the reproduction of potato virus Y (PVY) and potato virus X (PVX) on tomato plants (Solanum lycopersicum L.) and to stimulate the growth of infected plants by regulating the redox balance was demonstrated. The bacterial strains B. subtilis 26D and B. subtilis Ttl2 reduced the titer of PVY and PVX in tomato plants, restored their growth to the control values, which was accompanied by a decrease in the disease symptoms and severity. PVY and PVX disrupted the redox balance of plants for their development. However, the treatment with B. subtilis 26D and B. subtilis Ttl2 strains regulated the generation of hydrogen peroxide by changing the activity of catalase and positively affected the activity of peroxidases in tomato plants infected with PVY or PVX. This allowed us to suggest the possibility of using these strains as a basis for creating biopreparations for the protection of tomato plants from viral diseases.