Cercetări privind influenţa fertilizării şi al amestecurilor complexe din structura covorului vegetal al unor pajişti temporare asupra microflorei solului

Abstract

Researches were carried out on south region of Moldavian plain, studying the effects of fertilization and different ratio of perennial fodder plants (grasses and legumes) from vegetal canopy of two temporary meadows on soils microflora. Perennial fodder legumes were represented by Medicago sativa and Lotus corniculatus, and the perennial fodder grasses by Dactylis glomerata, Festuca pratensis, Poa pratensis and Lolium perenne. The temporary meadows have been fertilized with an unconventional product (Vinasse), and with different doses of organic (dung) and chemical fertilizers (N, P). The by-product Vinassa Rompak (3% N, 0.5% P, 7% K, pH 7-8), resulted from the yeast obtaining technology process, can be a good fertilizer and a factor for maintaining the balance between the soils microorganisms populations. The objectives of this investigation were to isolate and quantify the existing microbial population in soil (Gram positive bacteria, Gram negative bacteria, micromycetes and the nitrogen-fixing bacteria) establishing their participation ratio, the main fungus genres which activate in soil and their activity level for each variant. The results illustrate the influence of the fertilization on the total number of microorganisms, on the relationship between the main groups (bacteria and fungi), and on the micromycetes spectrum determined in each variant of our experiment.