EFFECTIVE STERILIZING PREPARATIONS FOR SUPPRESSING MICROBIAL GROWTH ON ROBINIA PSEUDOACACIA L. EXPLANTS IN VITRO

. Currently, the study of the possibility of using broad-spectrum biocides to suppress the microbial growth is relevant because of the presence of infection in explants after their sterilization with common disinfectants – sodium hypochlorite (“Belizna”), hydrogen peroxide solution (H2O2), silver nitrate (AgNO3). The five pure microbial strains have been isolated by laboratory methods from the model plants R. pseudoacacia L. in vitro. The goal of the study was to determine the efficiency of chemical biocides against specific microorganism types in R. pseudoacacia in vitro. The research was carried out in 2021–2022 at the Laboratory of Biotechnologies of the FSBSI “Federal Scientific Center of Agroecology, Complex Melioration and Protective Afforestation of the Russian Academy of Sciences”. The objects of the study were pure strains isolated from the affected explants of R. pseudoacacia L. We studied the effect of preparations (those that are used in standard protocols for the sterilization of R. pseudoacacia and first-proposed for microbial growth suppression: “Dezover”, 5%; “Proxel GXL”, 2 % and 5 %; “Dezavid”) on the growth of the isolated pure strains. For all preparations used in the study, the mean growth inhibition zone of strains in the nutrient agar was determined. The diffusion method from the holes to the agar was used to test the efficiency of the microbial growth suppression. Among the studied preparations, “Dezover”, 5 %; “Dezavid” (polyhexamethylene guanidine concentration – 0.14 %) and “Proxel GXL” effectively suppressed all isolated microorganisms. “Proxel GXL” (2 % and 5 %) showed the highest efficiency among the studied preparations, exceeding “Lysoformin” (1% and 5%) by 42% and 90%, respectively. The average delay zones for these preparations were more than 25 mm. This confirms the high sensitivity of the microorganisms isolated during these preparations’ study. The strains were not sensitive to AgNO3 (0.1 %), H2O2 (10 %) and NaOCl (“Belizna”, 10 %) by 100 % and 60 % (for the last two preparations), respectively. The research serves as the basis for the development of the protocol for the sterilization of explants R. pseudoacacia in vitro