Prospects for the use of Hypomyces odoratus as a basis of fungicidal preparation
The studies aimed to develop a method for obtaining enzymatic-active biomass of a mycophilic fungus with antagonistic properties against phytopathogenic fungi from animal and poultry waste. The object of the study was Hypomyces odoratus 94/77. It was deposited under collection number F-242 as a producer of hydrolytic enzymes. A modified Czapek-Dox medium with soybean flour was used as a background. The producer was grown under submerged conditions for 72 h at a temperature of 24-26 С. The proteolytic activity after the completion of cultivation was determined by the Anson method; the antibiotic activity was determined by the agar-agar diffusion method. The effect of pre-sowing treatment of seeds was investigated on the spring wheat variety Yugo-Vostochnaya 2 by known methods. The appropriate culture media with 0.5% pig manure or poultry droppings were used as controls. The change in the titer of Hypomyces odoratus during growth on the solid fraction of organic animal waste was assessed by the number of colony-forming units. When growing the fungus in deep conditions, the protease activity reached 370-460 PU/mg; the diameter of Bacillus subtilis growth suppression zone was 12-16 mm; biomass accumulation was 9.0-12.0 g/L. The culture liquid showed antagonistic properties against the phytopathogenic fungi Alternaria tenius, Bipolaris sorokiniana, and Helmintosporum sativum (the diameter of the growth inhibition zone was 24-32 mm) and bacteria Bacillus subtilis, Staphylococcus aureus, and Pseudomonas putida (16-22 mm). Pre-sowing treatment of wheat seeds with a culture liquid increased the germination energy, in comparison with the corresponding control, by 11.0-17.2%; it also increased laboratory germination by 18.6-20.0%. The height of the shoots and the length of the roots when using this agricultural method on the 7th day of growth reached 43.1 -48.2 mm and 38.0-43.2 mm, respectively, while in the control it did not exceed 27.5-28.5 mm and 26.0-27.3 mm, respectively. The solid fraction of pig manure and chicken droppings provided a massive increase in the biomass of the fungus. The titer of Hypomyces odoratus in organic substrates after 7 days of growth was 6.1x108 CFU/kg.