PRODUCTIVITY OF WINTER WHEAT VARIETIES DEPENDING ON VARIOUS PLANT PROTECTION SCHEMES IN THE SOUTHERN STEPPE

The article presents the results of studying the influence of plant protection systems on the structure of productivity of soft winter wheat varieties, when using plant protection products. The lowest plant productivity at the level of 4.75 t/ha was on the plots of the Zira variety without plant protection, and on the Ovidii variety with integrated plant protection it increased to 6.17 t/ha. The use of plant protection on the Zira variety and without plant protection contributed to an increase in yield by 4.0–15.2%, and on the Ovidii variety – by 5.7–18.7%. On average, the use of the Ovidii variety increased the yield by 5.3–9.2% in all variants of the use of plant protection compared to the Zira variety. The difference in the weight of grains per ear between the studied variants of the varietal composition and the use of plant protection was even greater and amounted to 15.4–31.6%, which indicates a positive effect of the studied factors on the productivity of winter wheat varieties. The analysis of variance revealed the maximum specific impact on the formation of the yield from plant protection (50.3%). The effect of the varietal composition was 21.8%, and was also high, as was the interaction between the studied factors – 19.2%. The use of plant protection in the experiments had a weak effect on the indicators of the mass of 1000 grains. A tendency to increase this indicator by 1.4–5.6% was determined with different combinations of the studied factors. On the contrary, a clear dependence was found on the gluten content of the increase in this indicator when using plant protection by 3.9–15.2 and 1.4–11.1% in the Zira and Ovidii varieties, respectively. High grain productivity parameters are corrected with the data of the analysis of the ear structure. According to the indicators “mass of grains per spikelet” and “mass of grains per spikelet”, an increase of these indicators was noted when using the studied varieties and applying plant protection by 3.3–23.7%. The use of plant protection ensures the production of grain of groups I-II according to the VDK index, which belong to class 2–3.