Precursors, fertilizers and pesticides effect on the prevalence and taxonomical composition of soft spring wheat variety Altaiskaya 75 seed infection

The aim of the paper is to study the effect of crop rotation, fertilizers and pesticides on the prevalence and taxonomic composition of seed phytopathogenic fungi in the soft spring wheat variety Altaiskaya 75 (Triticum aestivum L.) in the Sukhobuzimo and Minusinsk Districts of the Krasnoyarsk Region. In contrast to the general prevalence, the taxonomic composition of the causative agents of the seed infection differed statistically significantly (pFusarium spp. (50.4 %), while B. sorokiniana and Alternaria spp. occupied 19.8 and 29.7 % of the pathocomplex. In contrast to the Sukhobuzimo District, in the Minusinsk District, the proportions of Fusarium spp., B. sorokiniana, and Alternaria spp. amounted to 36.3, 46.9 and 16.8 %, respectively. The use of fallow as a precursor did not affect the overall prevalence of seed infection, but statistically significantly reduced the proportion of Fusarium spp. in the complex of causative agents of seed infection by 1.6 times (from 53.5 to 33.8 %) compared with the variants where wheat served as a precursor. Pesticides significantly reduced the prevalence of seed infection (pBipolaris sorokiniana, the fertilizer increased the prevalence of the fungus in both fallow and wheat backgrounds as precursors. In the case of Fusarium spp. the fertilizer reduced prevalence when used with wheat as a precursor and had no effect when used with fallow as a precursor.