Parasitocenotic Aspects in Phytoparasitology

The term "microparasitocenosis" proposed by A. P. Markevich, who combined parasitizing forms of resident microflora of the organism and parasites that entered from external environment. Viruses, viroids, bacteria, fungi, protozoa, phytohelminths, phytoparasitic mites and insects form the parasitocenosis in a macroorganism (plant) and represent a damaging complex that contributes to pathological changes in the macroorganism. The intention to simplify complex biological processes as much as possible has led to artificial isolation of any single pathogen. This turned out to be necessary and effective in studying causative agents of dangerous plant parasite infections. But it turned out to be inconsistent for associated infections and invasions since complex diseases develop when they are combined with other phytoparasites. Their synergism contributes to high harmfulness of complex diseases. Unfortunately, the problem of plant parasite infection and invasion has not been sufficiently studied in phytoparasitology. As defined, plant parasitism has boundaries from positive to neutral interactions of other types that are precisely outlined by pathogenicity. Harmfulness is exactly what can explain centuries-old hostility towards parasites. We considered the plant parasite cenosis of strawberries that included 27 plant parasites and 25 pathogens. The discovery of relationships between phytopathogens and phytoparasites has resulted in a qualitative change in cognitive tools and the interpretation of various pathogenic process phases. Based on systemic analysis, phytoparasites at different levels (plants, plant populations, biocenosis) are considered not as a mechanical population but as an integral system that functions under specific laws. Systemic quality of the plant parasitic cenosis appears in its interactions with other organisms.