Formation of phytopathogenic mycobiome on vegetative organs of plants in winter wheat

Abstract

Cultivated plants, which are characterized by high resistance to phytopathogenic microorganisms, create significant selective pressure on their populations and select highly pathogenic and aggressive forms. Highly susceptible plants to such microorganisms ensure a rapid growth in the population of phytopathogenic micromycetes in agrocenoses. Cultivation of such plant groups on production crops leads to an increase in biological pollution of the agrosphere and a significant decrease in the level of biological safety. This requires increased use of chemical means of plant protection against diseases, which causes chemical pollution of agroecosystems and leads to a significant decrease in the quality of plant products through the accumulation of metabolic products of phytopathogenic microorganisms in it and a decrease in biological safety in agrocenoses. Therefore, the assessment and selection of winter wheat varieties as a factor in the regulation of the phytopathogenic mycobiome in agrocenoses is a highly relevant area of research that ensures the selection of ecologically safe varieties of cultivated plants. Cultivation of such varieties leads to a decrease in the level of biological pollution in agrocenoses and increases the quality and safety of plant products. It is known that biotic, abiotic and anthropogenic factors affect the formation of populations of microorganisms. Therefore, the formation of the mycobiome on the vegetative organs of winter wheat during the ontogenesis of plants under traditional and organic technologies was investigated. It has been proven that the meteorological conditions during the years of the study, namely: high air temperature and a significant amount of precipitation during the growing season, which was observed in 2021 and in the long dry years of 2020 and 2022, had a significant impact on the formation of the population of micromycetes in the agrocenosis of winter wheat. According to the results of our own research, the population density of micromycetes and the intensity of sporulation of mushroom species decreased during the phase of emergence into the tube using traditional cultivation technology. At the same time, during the earing phase, mushroom sporulation increases by 2–3 times. This can be explained by the homeostatic reaction of the population of micromycetes in the mycobiome of vegetative organs of winter wheat plants to the chemical pressure of applied pesticides, which can cause contamination of agrocenoses with infectious structures of pathogens and their toxic metabolites. At the same time, the population density of micromycetes, under organic cultivation technology, increased during the growing season from the tillering phase to the earing phase, depending on the soil and climatic conditions. Under the conditions of various winter wheat cultivation technologies, significant changes in the formation of micromycete populations were observed due to the influence of varietal characteristics of plants. A significantly lower frequency of occurrence of species and their intensity of sporulation was observed on the vegetative organs of the Skagen variety, compared to winter wheat plants of the Podolyanka variety. This testifies to the ability of physiological and biochemical substances of plants of various varieties of winter wheat to stimulate or restrain the development of micromycetes in the mycobiome of vegetative organs of the culture. Evaluation of the plant variety based on indicators of influence on the density, frequency of occurrence and intensity of sporulation of micromycetes will ensure a decrease in the level of biological pollution and an increase in the biosafety of plant raw materials.