Effectiveness of the use of biopreparations and fungicides in the cultivation of spring wheat in the forest-steppe of the Priobye

Abstract

The data on the effectiveness of using chemical, fungal and bacterial fungicides to treat seeds and crops of spring soft wheat in order to limit harmfulness of major diseases are presented. The research was conducted in 2020–2022 on chernozem leached forest-steppe of the Novosibirsk region Priobye. Chemical seed protectant Scarlet and its mixture with Vitaplan were the most effective dressers in the fight against root rots. It has been demonstrated that although biopreparations are inferior in efficiency to chemical ones, they act for a longer period of time and protect the plant from the disease for a longer period of time. Seed dressing with chemical preparation reduced the development of leaf diseases by 53–58%, and with biopreparations – by 34–41%. Titul 390 was the most effective of the vegetation treatments – 60–98%. The efficiency of the biopreparations was 42–64% in the years of moderate disease development. In the years of strong development of septoriosis or powdery mildew, the efficiency of biopreparations did not exceed 22–30%. The biological preparations had a growth-stimulating effect on the plants: they increased the flag leaf area by 22–39%. The seed treatment showed an increasing trend in the number of spikelets, grains per ear and grain weight per ear. Application of the preparations during the vegetation period increased reliably the ear length by 16–28%, the number of spikelets – by 15–20, grains – by 24–31, grain weight per ear – by 33–51%. At seed dressing the greatest increase in the yield (0.15 t/ha) was provided by Scarlet, when using a mixture of biological and chemical preparations it amounted to 0.11 t/ha. When treated during the growing season, chemical fungicide increased the yield by 0.33 t/ha, while biopreparations increased the yield by 0.11–0.14 t/ha. Complex use of chemical preparations (Scarlet + Titul 390) provided the maximum yield increase – 0.62 t/ha, from the joint use of chemical and biological preparation the yield increased by 0.15–0.33 t/ha. The biological preparations increased this indicator by 0.13–0.23 t/ha. It has been concluded that it is possible to select combinations of chemical and biological preparations that can control phytosanitary situation and provide acceptable yield.