Fungal diseases of corn seeds

Corn is a strategic crop with growing demand, which necessitates increased production and the use of healthy seeds to improve yields and product quality. The purpose of the study was to investigate the symptoms of fungal diseases of corn seeds and establish the spread of micromycetes. The study of diseases of corn cobs and seeds was carried out in the Problem Research Laboratory of Mycology and Phytopathology of the Department of Phytopathology of the National University of Life and Environmental Sciences of Ukraine. Samples of plant material (cobs) for diagnostics were taken during route surveys in the Forest-Steppe of Ukraine and during the period of their storage. Seed samples were taken after harvesting. Diagnosis of diseases was carried out by visual examination and biological method (seed germination in wet chambers and on a nutrient medium). Microscopic analysis of their morphological structures was performed to identify micromycetes. The frequency of occurrence of micromycetes was determined during seed germination in petri dishes on filter paper. During the studies, infection of corn cobs and grains with various micromycetes was detected (Trichothecium spp., Fusarium spp., Alternaria spp., Cladosporium spp., Aspergillus spp., Mucor spp., Penicillium spp., Rhizopus spp.), which caused the variability of disease symptoms. The parasitism of the fungi Botrytis cinerea and Bipolaris spp. on ears of corn was established, which was not disclosed in the national scientific literature. The highest frequency of occurrence on corn seeds was characterised by representatives of the genus Alternaria – 18.4%. Fungi of genera Cladosporium and Penicillium were detected on 4.5 and 4.7% of seeds, respectively. Seed infection with Fusarium spp. was 2.7%, Mucor spp. – 2.6%. Representatives of the genus Rhizopus were identified on 1.1% of seeds. Fungi of genera Trichothecium and Aspergillus were 0.4 and 0.6%. Therefore, monitoring of fungal pathogens and their phytopathological examination are necessary to assess the quality of corn seeds. Information on the symptoms of mycoses, the species composition of micromycetes should be used in the diagnosis of seed pathologies