BIORATIONAL METHOD OF AMBROSIA ARTEMISIIFOLIA L. GROWTH AND DEVELOPMENT INHIBITION

Currently, the search for biological agents that are alternative to chemical ones to protect agrocenoses from weeds, including quarantine objects like different types of ragweed, is relevant because they cause biological and technological damage to the environment, agriculture and have a negative impact on human health. The research was aimed at searching for biotically active elicitors of plant and microbial origin for the induction, reinforce of oxidative stress and inhibition of Ambrosia artemisiifolia L. growth. Strains were searched for and studied in 2019–2020 in laboratory experiments and greenhouse trials in the Research Institute of Agriculture of Crimea. Ragweed plants were grown in pots. Soil – chernozem southern. In the phase of 4–6 leaves, plants were treated with biorational preparative forms based on microbial and plant elicitors at a dose of 200 mkl/plant. For bioherbicidal composites, strains-inhibitors from the Research Institute of Agriculture of Crimea collection (CCM), plant extracts from the ragweed and glycerin were used. The inhibition efficiency was evaluated three weeks after treatment. The indices of height, phytomass, antioxidant status and ragweed damage degree were taken into account. We identified seven strains that inhibited plant growth by 0.13–1.08 g/plant (37–38 %) compared to the control variants: 1) water treatment, 2) bacterization with a phytopathogenic strain of Stagonosporopsis heliopsidis from the All-Russian Scientific Research Institute of Plant Protection collection. For the first time, we used ambrosia BAS to develop a birational herbicide to control the ragweed. Bacterization with biorational preparative forms based on biotically active elicitors of plant and microbial origin affected the homeostasis of ragweed, induced plant stress by blocking the enzymatic activity and the antioxidant protection systems. The activity of catalases and polyphenoloxidases decreased by 2.9–85.6 and 1.2–658.0 times, respectively, with a significant correlation between themselves (r = 0.66) and the correlation of catalase activity with plant phytomass (r = 0.72). The content of glutathione decreased by 2.5–2.7 compared to the control and had significant correlations with the activity of catalases (r = 0.63) and the phytomass of ragweed (r = 0.80) (p < 0.05) depending on the components of the biohebicidal formulations.