Change in biological activity of ordinary chernozem and productivity of forage meadow agrocenose under the effect of biofertilizers.

摘要

This study was conducted to investigate the efficacy of the effect of biofertilizers (Vesna and Belogor) on the productivity of a forage agrocoenosis and the biological activity of ordinary chernozem from the Botanical Garden of the Southern Federal University in Russia. Investigations were performed in May to August 2005-2007 under conditions of a perennial meadow agrocoenosis created by the mosaic planting method in 1987 on ordinary chernozem. The composition of the six species agrocenosis contained lucerne (Medicago sativa), birdsfoot trefoil (Lotus corniculatus), red clover (Trifolium pratense), meadow fescue (Festuca pratensis), smooth bromegrass (Bromus inermis), and orchard grass (Dactylis glomerata). The basis of the biofertilizer Vesna is a lysine concentrate solution containing amino acids, B vitamins, trace elements, mineral and organic substances, and the complex mineral fertilizer nitroammofoska (azofoska) with a content of nitrogen, phosphorus, and potassium of 16% each at a rate of 100 kg/1000 litre of liquid lysine concentrate. The biofertilizer Belogor of series KM-104 contains a set of lactic acid and propionic acid bacteria, yeasts, and phytopathogenic cultures of microorganisms of the genera Bacillus and Pseudomonas, as well as bacterial metabolic products, macro- and microelements necessary for vital functions of microorganisms and beneficial for plant development. The use of biofertilizers had a positive effect on the productivity of aboveground phytomass of the meadow agrocenosis, which on average was 1.4 times higher than in the control variant. With respect to productivity, the most responsive crop to the application of biofertilizers, especially Belogor, was lucernce and the least responsive was birdsfoot trefoil. The number of bacteria utilizing organic and mineral nitrogen and microscopic fungi utilizing organic nitrogen were on average 15.0-81.7% higher than in the control. Investigating the enzyme activity of ordinary chernozem revealed that enzymes were at the same level in all variants prior to applying biofertilizers. After the application, they increased on average by 1.14-2.20 times; the effect of Vesna was stronger.