Microbiome of ampelocenoses of various soil types

Abstract

Grapes hold a prominent position in global agriculture, and their successful cultivation is closely related to the microbiological composition of the soil, which influences both fertility and plant health. This study aimed to investigate the structural organization of the soil microbiome in different grape-growing soils. Soil samples were collected from both the rhizosphere and non-rhizosphere zones of wild grape plants growing on brown forest and alluvial meadow soils. Additionally, soil from the ampelographic collection of the Kuban State Agrarian University characterized as leached chernozem, sampled in the central zone of the Krasnodar Krai, was examined. Microorganisms were identified using serial dilution techniques followed by culturing on selective media. The analysis focused on quantifying key microbial groups, including phytopathogenic fungi, ammonifying bacteria, nitrogen fixers, cellulolytic bacteria, nitrifiers, and denitrifiers. An agrochemical assessment of the soils was also conducted, measuring parameters such as humus content, nitrate nitrogen, available phosphorus, and potassium levels. The highest numbers of micromycetes and ammonifying bacteria were isolated from soil samples of native alluvial meadow cenoses. In contrast, native brown forest soils harbored the greatest abundance of nitrogen-fixing, cellulolytic, nitrifying, and denitrifying microorganisms. Agrochemical analysis revealed significant differences among the samples in electrical conductivity, humus content, nitrate nitrogen, phosphorus, and potassium concentrations. Correlation analysis identified several relationships between agrochemical properties and microbial abundance. A strong positive correlation was found between bacterial colony-forming units (CFUs) and agrochemical parameters (R = 0.92), while a weak negative correlation was observed between fungal and bacterial populations (R = –0.056). Overall, a reduction in both the abundance and diversity of soil microorganisms was noted in cultivated ampelocenoses compared to native grape cenoses.