Effect of bacterization with Aeromonas media GS4 and Pseudomonas extremorientalis PhS1 on wheat seedlings under different abiotic conditions

We studied the effect of soft wheat seed treatment (Triticum aestivum L.) with two bacterial strains (Aeromonas media GS4 and Pseudomonas extremorientalis PhS1) isolated from earthworm coprolites on the growth and development of wheat seedlings in a 12-day laboratory experiment, as well as on root rot disease and the activity of guaiacoldependant peroxidase under optimal conditions and abiotic stress (elevated and low temperatures and moisture content). We established that growing nonbacterized wheat plants under stress abiotic conditions reduced the height of plants compared to growing under optimal abiotic conditions, and seed bacterization with P. extremorientalis PhS1 strain increased wheat plant height (by 9-15%) under stress abiotic conditions compared to the nonbacterized plants. Bacterization with both strains decreased infestation of wheat seedlings (2.5-4 times) by root rots under unfavorable abiotic conditions compared to nonbacterized plants. In addition, under optimal and arid conditions, bacterization with P. extremorientalis PhS1 strain was the most effective, and under humid conditions it was bacterization with A. media GS4 strain. We showed that the activity of guaiacoldependant peroxidase correlates with the development of plant resistance to abiotic stress. In our experiments, plant bacterization resulted in a 2-fold increase in peroxidase activity both in leaves and roots of wheat plants compared to the nonbacterized plants. As the result, the ability of bacteria to activate peroxidase can serve as an information indicator of strengthening protective mechanisms of plants during bacterization. The paper contains 4 Figures and 34 References.