FIELD: agriculture, plant growing. SUBSTANCE: it is suggested the composition for chemical protection in plants including, at least, one toxic substance and target additives as efficiency quantity of preparation obtained due to successive extraction of Mortierella strangulata micromycete with nonpolar extragent in supercritical state with water, alkali, water, acid, water, alkali and water followed by combining solid residue with the first extract, and, also, method for treating plants at manufacturing plant growing production with above-mentioned composition at the quantity of 0.1-20 mg/ha planting or 0.5-10000 mg/t sowing material at recalculation for total content of chitosan, arachidonic and eucosapentaenic acids. The innovation enables to enhance action spectrum of obtained product to treat plants and raw material basis, increase coefficient of raw material usage in manufacturing product to treat plants. EFFECT: higher efficiency of production. 2 cl, 5 ex, 3 tbl _
