Effect of strains Azotobacter chroococcum and Azospirilum lipoferum on the yield of sugar beet and microbiological activity of soil

Abstract

The effect of the highly efficient strains Azotobacter chroococcum and Azospirilium lipoferum was studied on the yield of two varieties of sugar beet and on the microbiological activity of the carbonate chernozem, on which this crop was cultivated. Investigations have shown that the application of nitrogen-fixing bacteria may exert higher yield of root and crystal sugar, but at the cost of decrease in potassiumn, atriuma nda lpha-aminon itrogeni n sugarb eet.T he useo f nitrogen-fixing bacteria resulted in a higher total number of microorganisms, more numerous ammonifiers, actynomicetes, oligonitrophilic bacteria and in a stronger dehydrogenasis activity, whereas fungi decreased in number.