Effect of Organic Cultivation on the Occurrence of Beneficial Groups of Microorganisms in the Rhizosphere Soil of Vegetable Crops

The article presents the results of research on the occurrence of beneficial groups of microorganisms in the rhizosphere of carrot, parsley and potato plants after the application of: (1) a commercial product EmFarma Plus (Probiotics Polska), (2) a consortium called Skierniewickie Microorganisms (MS) (containing three strains of Klebsiella oxytoca, Pseudomonas fluorescens, Pseudomonas sp.), and (3) Consortium MS together with EmFarma Plus. The study estimated the populations of microscopic fungi and bacteria, including the groups of microorganisms considered to be beneficial, i.e., spore-forming bacteria, fluorescent bacteria of the genus Pseudomonas, diazotrophs and actinomycetes. Applications of Consortium MS and, to a lesser extent, the preparation EmFarma Plus together with Consortium MS resulted in a significant increase in the total population of diazotrophs isolated from the rhizosphere soil of the vegetable species included in the study. There was no significant impact of the application of EmFarma Plus on the population size of the analyzed groups of microorganisms in the rhizosphere soil.