Vaga L. Azotobacter in soils of Forest-steppe of Ukraine: distribution and biological activity.

Dissertation work is devoted to studying of distribution and biological activity of bacteria of sort of Azotobacter in soils of Forest-steppe of Ukraine and selection of the most active cultures, which can influence on the productivity of winter wheat. The systematic observation on a quantity and activity of Azotobacter in soils of agroecosystems of Forest-steppe of Ukraine showed that its quantity and biological activity depended on the terms of edaphotop of its existence. It is ascertained that ab-solute dominant in soils of Forest-steppe of Ukraine is a type of A. chroococcum. From typical black soil is selected a new culture A. vinelandii 12M, which has a complex agronomical valuable properties, and is characterized by the high level of nitrogen fixing productivity, stimulations of plants growth, mobilization of difficultly soluble phosphates of soil, oppressing of phytopathogenic mushrooms development. In a vegetation and field experiments of winter wheat seeds inoculation with culture of A. vinelandii 12M stimulated growth of plants, increased accumulation of dry matter in phytomass, promoted the yield on 7-13% and maintenances of gluten in a corn on 0,8%.