Pool and diversity of prokaryotes of carbonate chernozem of long-term field experience of Moldova

Abstract

For the first time in Moldova, changes in microbiological indicators obtained using polymerase chain reaction (PCR) in carbonate chernozem were studied depending on the type of land use under different anthropogenic loads. The work used soil samples from winter wheat crop rotation of long-term field experiments of different types of use: without fertilizers, mineral and organic background, as well as 75-year-old fallow land. A high diversity of genetic information with a spectrum consisting of 17 phyla was established. According to the International Committee on Prokaryotic Taxonomy (2021), they are new, identified and / or confirmed by metagenomic analysis. The prokaryotic pool varied from 0.01% to 46.53%: Actinomycetota (38.17-46.53%), Pseudomonadota (19.60-27.02%), Bacillota (7.32-22.40%), Bacteroidota (5.31-8.55%), Acidobacteriota (1.94-3.32%), Verrucomicrobiota (1.37-2.09%), Myxococcota (1.09-1.71%), Nitrospirota (0.15-0.65%), Planctomycetota (0.58-0.65%), Gemmatimonadota (0.36-0.58%), Patescibacteria (0.08-0.17%), Cyanobacteriota (0.05-0.08%), Chloroflexota (0.03-0.07%), Fibrobacterota (0.01-0.05%), Abditibacteriota (0.01-0.07%), Bdellovibrionota(0.01-0.011%), and Nitrososphaerota (7.32-22.4%). The first 16 are representatives of the Bacteria domain, and the Nitrososphaerota phylum belongs to the Archaea domain. Based on the results of multiple observations of the content of conserved DNA regions of different phylogenetic groups in the soil, it can be concluded that the prokaryotic community is susceptible to the type of chernozem use. As an alternative to soil conditions, bacteria act in the following sequence: soil without fertilizers → organic background → mineral background → fallow land, and archaea - vice versa.