ВПЛИВ PANTOEA AGGLOMERANS НА СТАН І АКТИВНІСТЬ ФОТОСИНТЕТИЧНОГО АПАРАТУ ЗЕРНОВИХ КУЛЬТУР

Current interest to Pantoea agglomerans is due to its biodiversity and beneficial properties of metabolites and, on the other hand - exist need to investigate its harmfulness. Purpose. Investigation of Triticum aestivum L. and Secale cereale L. cereal crops plants infection with P. agglomerans strains on photochemical and enzymatic activity of these crops photosynthetic apparatus. Methods. Bacteria cultivation and suspension preparation were carried out using conventional methods, artificial plant inoculation with obtained suspensions was performed by injection to the culm of rye and wheat in the booting stage. Photochemical activity of leaves was determined using chlorophyll fluorescence induction method. The activity of antioxidant enzymes was determined by the rate of decomposition of hydrogen peroxide: catalase - permanganatometrically, and peroxidase - by reaction with benzidine and further photometry. MS Excel was used for statistical analysis. Results. Data of effects of Triticum aestivum L. and Secale cereale L. plant inoculation with P. agglomerans pathogenic strains isolated from S. cereale L. seeds on the antioxidant enzymes activity of leaf tissue and photochemical activity of photosynthetic apparatus are generalized. The most significant changes in the activity of antioxidant enzymes of rye leaves was revealed under the conditions of artificial infection of P. agglomerans 7460, compared with intact plants of S. cereale L.: peroxidase activity increased almost twice, and catalase - by 32.6%, which may be due to hypersensitivity reaction activation. An increase of peroxidase activity by 50.4% and decrease of catalase activity by 48.4% compared to intact plants was detected in leaves tissue after T. aestivum L. plants inoculation with P. agglomerans 7604 isolated from S. cereale L. seeds. It was shown that S. cereale L. and T. aestivum L. plants inoculation with P. agglomerans 7460 phytopathogenic bacteria from S. cereale L. seeds led to a more significant inhibition of photosystem II (PSII) quantum efficiency and T. aestivum L leaves assimilation activity than S. cereale L., which indicates a greater adaptive potential of this pathogen. Conclusions. It was found that inoculation of S. cereale L. plants with P. agglomerans 7460 that may cause pathological process in this plants species, led to a significant increase in the activity of plant oxidoreductases in leaves tissues - catalase and peroxidase. Different effect of non-specific for T. aestivum L. P. agglomerans strains inoculation on the activity of leaf tissue oxidoreductases compared with intact plants was detected: P. agglomerans 7604 infection decreased the activity of both researched oxidoreductases, and P. agglomerans 7460 inoculation decreased catalase at increased peroxidase activity, which may be due to the difference in the chemical structure of this strains exometabolites. After P. agglomerans 7604 inoculation, the slow phase of photosynthesis was limited, and, therefore, the carbon assimilation rate of T. aestivum L. after P. agglomerans 7460 inoculation showed more significant inhibition of leaves photochemical activity. A decrease in both the quantum efficiency of PSII and the activity of carbon assimilation was observed, which may indicate greater adaptability of the second strain. [ABSTRACT FROM AUTHOR]