Innovative ways of suppression of fungal infections of plants:approaches, solutions, outlooks

In order to study the possibility of suppressing mycoses with fumigation pyrotechnic compositions, biologically active compositions were developed based on compounds synthesized according to original methods in the organic synthesis laboratory of the Federal State Scientific Institution "All-Russian Research Institute of Phytopathology", synthetic fungicides from the azole group, as well as natural antimycotics from the polyene group obtained by microbial fermentation of Streptomyces bacteria, followed by extraction of supernatants and preparative column chromatography of extracts. Pyrotechnic compositions of fumigation action were developed, including active substances of biologically active compositions (23 ... 46%), oxidizer (22...56%), combustible substances (15...56%), flame arresters (14...34%), phlegmatizers (6...20%) and baking powder (4...8%). The stability of complexes of synthesized compounds with putative cellular targets: ergosterol; ergosterol-dependent membrane Na⁺/K⁺-ATPases; 14α-demethylases controlling the conversion of lanosterol to ergosterol; and squalene-monooxygenases catalyzing the synthesis of squalene–epoxidase, a lanosterol precursor, was studied using computer modeling methods in the B3LYP/DZP approximation using the ChemCraft and FireFly software package. It was found that the synthesized compounds with nitro groups in the molecule selectively coordinate with the Na⁺/K+-ATPase membrane enzyme site responsible for phosphorylation and binding to ATP. It is revealed that the nitrogen atom of synthesized benzoxazines selectively coordinates with the iron of Gemma 14α-demethylase, and the binding energy of the complex is significantly lower than the coordination energy of iron with the cysteine residue of the protein matrix of the enzyme. It was fixed that the synthesized compounds at a concentration of 16-500 mcg/ml have fungicidal activity against test cultures Fusauium graminearum, Alternarium alternata, Bipolaris soraciniana, comparable to the activity of comparison drugs phytolavin and previcur. It was fixed that the samples of pyrotechnic charges of fumigation action developed in the laboratory of organic synthesis of the Federal State Scientific Institution VNIIF have fungicidal activity against the phytopathogenic fungi F. graminearum, A. alternata, B. soraciniana with an effective action of 23 ... 69% of the test cultures. For wheat affected by the tested crops, the effectiveness of pyrotechnic charges was in the range of 12 ... 31% of the death of test crops. It is revealed that the fumigation method of plant mycosis suppression implemented in this work, integrated with modern methods of medical chemistry, organic synthesis and classical methods of chemical treatment, is an effective innovative solution and can be used in the development of food security strategies.