Yield of spring wheat varieties of different dates of zoning when grown under intensive technology in the forest-steppe of the Novosibirsk Ob region

Analysis of grain production in Siberia reveals a clear discrepancy between the number of new varieties of grain crops (many dozens) and the almost complete absence of growth in the five-year average grain yield in the last two to three decades. The aim of the study was to compare the yield and grain quality of a modern intensive variety of spring wheat (Novosibirskaya 31) and an old (conditionally) extensive variety (Saratovskaya 29), released in Western Siberia more than 60 years ago. It is important to understand what valuable qualities the modern variety has acquired over such a long period of breeding. The varieties were compared under conditions of intensive cultivation technology with the application of increasing doses of nitrogen fertilizer (N30, N60, N90) against the background of a complex of plant protection products against pests, weeds, diseases and field-raising. The study was conducted in 2019-2020 in the Central forest-steppe of the Novosibirsk Ob region on old plowed chernozem leached. It was found that at the beginning of the dose range varieties did not differ significantly in responsiveness to nitrogen fertilizer, forming almost the same grain yields up to 3.7 t/ha. At higher doses of nitrogen fertilizer, the yield of Novosibirskaya 31 variety began to significantly outpace the Saratovskaya 29 variety, which was due to the lodging of plants of the latter, despite the use of retardant. The yield of 3.7 t/ha is 1.5–2.0 times higher than the actual yields received by most Siberian farms, so the use of potentially higheryielding varieties in this situation is of no practical importance. Nevertheless, from the scientific point of view, it is important to continue research on the opportunities available to breeders to increase the average annual yield of crops by adjusting plant genotypes in areas with limited heat and moisture resources.