Based on the results obtained, it has been found that natural regulators as Verbascoside and Linarozide (standard) have a beneficial effect in regulating enzyme activity with an important role in vital plant processes. Oxidation-reduction processes in the leaves of Vistavocinaia and Noiabrskaia late varieties depend on developmental phenophases, environmental conditions, temperature, genotype, and substances used to treat plants. Thus, with the change of the activity of peroxidase and catalase during the phenophases we find their active participation in the metabolic processes, fulfilling functions of resistance and adaptation of the pear plants to the unfavorable environmental conditions, and consequently to the formation of the fruit harvest and quality.