PATHOGENIC MYCOBIOTA OF MAIZE SEEDS IN SOUTHERN RUSSIA

Abstract

Maize (Zeamays L.) is one of the key crops in the Russian Federation, with the southern regions of Russia accounting for up to 40% of the gross grain harvest. However, the realization of its genetiс potential is limited by an unfavourable phytosanitary background, leading to yield losses ranging from 25 % to 100 %. This review examines the most dangerous pathogens of maize diseases transmitted through seed material. The main damage is caused by fungal pathogens inducing common smut, northern leaf spot (northern helminthosporiоsis), charcoal rot, and ear rots. These diseases not only reduce crop yields but also lead to grain contamination with hazardous mycotoxins (fumonisins, zearalenone, deoxynivalenol, diplodiatoxins, and hetoglobosins), thereby limiting its use for food and feed purposes. The aim of the review is to systematize current data on the generic composition of fungal pathogens affecting maize in southern Russia, their biology, prevalence, and impact on the phytosanitary situation. The object of analysis comprises publications from 2011 to 2025 on fungal pathogens of maize in the southern regions of the Russian Federation, including Krasnodar Krai, Stavropol Krai, and the republics of the North Caucasus. For the first time in southern Russia, a comprehensive analysis of the pathogenic mycobiota of maize seeds has been conducted, which includes the systematization of data on eight genera of pathogens (including the poorly studied Sarocladium), an assessment of their role in mycotoxin accumulation, and an evaluation of the influence of abiotic stresses on disease development. It has been established that seeds serve as the main reservoir of infection. The research methods involved the analysis of relevant literature sources, taxonomic systematization of pathogens, and assessment of their prevalence in agrocenoses and virulence. The results systematize information on eight genera of pathogens: Ustilago, Exserohilum, Macrophomina, Fusarium, Stenocarpella, Nigrospora, Sarocladium, and Cochliobolus. Zones of increased infection risk have been identified: Macrophomina and Sarocladium are prevalent in steppe regions, while Ustilago and Fusarium are widespread across all areas. The practical significance of the findings lies in their potential to serve as a foundation for planning phytosanitary monitoring, developing regional plant protection programmes, and setting priorities in breeding for resistance to key pathogens. The materials are also applicable in educational courses on phytopathology and plant protection.