Effectiveness of Differentiated Application of Herbicides in Winter Wheat Crops

Abstract

The aim of the research was to compare the effectiveness of the differentiated and uniform application of herbicides on winter wheat crops in the northwest region of the Russian Federation. According to the research results, a stable positive correlation was found in the stemming phase of winter wheat between the NDVI vegetation index and the projective cover (r = 0.32–0.61, p ≤ 0.05) but not with the number of weeds (r = –0.18–0.35). Despite this, the actual values ​​of this index did not make it possible to reliably distinguish different degrees of weediness in plots in the experiment in all cases. The higher biological and economic efficiency of the uniform application in comparison with the differentiated application of the herbicide in winter wheat crops was shown. In this variant, weeds were destroyed, including those on plots with low infestation, which were not treated with the differential application of the herbicide. At the same time, differentiated herbicidal treatment contributed to a significant decrease in the volume of drug use. The herbicide consumption rate differentiated on the basis of measurements of the NDVI index turned out to be as effective in influencing the number and phytomass of weeds as the total rate.