Epiphytic bacterial complexes in grain crops: Taxonomic composition and antagonistic properties

It is shown that the taxonomic composition of epiphytic bacteria on the leaves of wheat and barley changes in the course of vegetation. Pseudomonas and Arthrobacter predominated on young leaves and were later replaced with the ageing of the leaves by bacteria of the hydrolytic block: myxobacteria and bacilli. Representatives of myxobacteria were found as dominants on grains in wheat and barley ears as well. Thus, the replacement of eccrisotrophs, which feed on plant excreta, with the bacteria of the hydrolytic block, which are capable of destroying dying plant tissues, was observed in the phyllosphere. Bacteria of the same taxa as those from the phyllosphere of the studied crops were isolated from the rhizosphere and the soil, where only the fraction of typical pedobionts increased, such as bacilli, Arthrobacter, and Rhodococci. It was established that the bacteria that prevail on the studied agricultural plants possess antibiotic activity toward three species of phytopathogenic bacteria used in the experiment, which indicates the protective role of epiphytic prokaryotes toward host plants.