The effect of fungi and bacteria symbiosis with switchgrass (Panicum virgatum L.) root system

Abstract

Purpose. To establish the symbiotic effect of symbiosis of fungi and bacteria with the root system of switchgrass (Panicum virgatum L.) in improving their growth and development and increasing productivity.Methods. Field, laboratory and statistical.Results. With the use of mycorrhizal fungi and nitrogen-fixing bacteria, positive results were obtained on their influence on the growth and development of plants and the yield formation. In particular, the leaf surface area in variants with the fungus Trichoderma harzianum Rifai. (Mycofriend) and Tuber melanosporum Vittad. (formulation Mikovital) and bacteria Bacillus subtilis Cohn. (formulation Florobacillin) for accounting for 30, 60, 90 and 120 days of the growing season was 3.2–13.2% higher compared to the control. Similarly, the mass of leaves and root system exceeded the control indicators by 5.1–24.4%, respectively. The height of plants in these terms of accounting was 4.4–13.7% higher than in the control. In addition, in these variants, the soil retention increased by 6.7–25.0%, and the proportion of soil lumps smaller than 0.25 mm decreased by 3.2–8.5% compared to the control. The yield of dry mass of switchgrass in variants with mycorrhizal fungi and nitrogen-fixing bacteria was 0.88–2.64 t/ha higher than in the control.Conclusions. Use of mycorrhizal fungi Trichoderma harzianum Rifai. and Tuber melanosporum Vittad. (formulations Mykofrend and Mikovital), as well as nitrogen-fixing bacteria Bacillus subtilis Cohn. (formulation Florobacillin) at their radical introduction into the soil contribute to the improvement of growth and development of switchgrass plants and increase the yield of dry biomass.