Role of factors in the spread of seed infection of spring wheat in the forest-steppe of the Krasnoyarsk Region

Abstract

Spring wheat forms the basis of Russia’s food security. The use of resource-saving tillage techniques exerts an ambiguous effect on the phytosanitary situation in spring wheat crops. The research goal was to evaluate the effect of basic tillage techniques and forecrops on the prevalence of root rot and subsequent accumulation of pathogens in the seed material of spring wheat in the forest-steppe of the Krasnoyarsk Region. Crop rotation courses were as following: green manure fallow (mustard) - spring wheat, annual grasses (oats + soybeans) - spring wheat. In the experiment of 2024-2025, the Novosibirskaya 41 soft spring wheat variety and Lamador Pro (SC) as pre-sowing seed treatment agent were used. Laboratory tests were carried out in accordance with the standard GOST 12044-93. The development of root rot in spring wheat crops after green manure fallow was lower than the corresponding index in wheat crops after annual grasses. Two-factor analysis of variance showed that the forecrop significantly affected the degree of damage to plants by root rot. No statistically significant differences in the indices in the tillage variants were revealed. The laboratory analysis of the seed infection showed the dominance of Alternaria spp. in the pathogenic complex followed by Bipolaris sorokiniana. Fusarium spp. accounted for the smallest proportion of seed infection in spring wheat after the forecrops under study. Significant effect on the proportion of Fusarium spp. was exerted by the tillage variant. The impact of the forecrop depended on the year (significant impact was found in 2024 only). The highest average affection score was typical for Bipolaris sorokiniana. Linear relationship was determined between the prevalence of root rot in spring wheat crops after green manure fallow and the occurrence of Fusarium spp. pathogens as part of the seed infection: the coefficient of determination R2 = 0.607, p < 0.05.