Endophytic microflora of winter barley grain in the Forest-Steppe zone of Ukraine

Abstract

Goal. To determine the level of infection of winter barley grain with endophytic microflora, to identify the isolated species of fungi and their frequency of occurrence during the years of research. Methods. The following laboratory research methods were used: isolation and identification of endophytic seed microflora using a nutrient medium. 67 samples of the winter barley harvest from different parts of the Forest-Steppe zone of Ukraine for 2017–2021 were analyzed. Results. During the research period, fungi belonging to 11 genera were isolated. Internal infection of winter barley grain varied in the range of 11–100% depen­ding on the year and place of sampling. The most frequently observed lesions were Alternaria fungi (100% of analyzed samples). Fungi of the genus Fusarium took the 2nd place in terms of detection frequency. The highest level of damage by fusarium pathogens was observed in the Western Forest Steppe in 2019, and in the Right Bank Forest Steppe in 2021. The pathogen Bipolaris sorokiniana was more often isolated from samples collected in the Western Forest Steppe of Ukraine, where their share in the complex reached 5.5%, in the Right Bank Forest Steppe it did not exceed 0.5%. Representatives of the genera Epicoccum, Penicillium, Aspergillus, Cladosporium, Mucor, Helminthosporium, Sordaria, and Stemfillium occurred much less often. In some seed samples, a rather high development of bacteriosis was noted. A negative correlation was established between the specific proportion of Fusarium and Alternaria fungi. Conclusions. The complex of endophytic microflora of winter barley seeds was dominated by fungi of the genera Alternaria and Fusarium. According to the frequency of detection, fusariosis was in the 2nd place. The presence of other mushroom species in the population was much lower. Since the dominant species are the producers of mycotoxins, systematic monitoring of the endophytic mycoflora of winter barley grain should be carried out and decisions about its use should be made taking into account the phytopathological assessment.