Efficiency of fertilizers and plants protection agrochemicals integrated application in culturing spring rape in the Altai region conditions

The purpose of research is to study the influence and interaction of chemical protection agents (herbicides, fungicides, insecticides) and nitrogen fertilizers on the productivity of spring rapeseed. Research was carried out to improve the system for protecting spring rapeseed from a complex of pests at different levels of nitrogen nutrition in 2014-2016. During the growing season of the crop, pests such as rapeseed sawfly, cabbage moth, cruciferous bugs, and rapeseed flower beetle were identified. The EPV was exceeded only in terms of the number of rapeseed flower beetle. The application of nitrogen fertilizers contributed to an increase in the competitiveness of the crop, which is reflected in a decrease in the amount of weed component and its mass and resistance to phytophages. The rapeseed flower beetle prefers less developed and more weedy crops. The biological effectiveness of the insecticide against the background of fertilizers was higher and amounted to 89.6 %, and against the background without fertilizers it was 88.1 %. In the variant without fertilizers and protective agents, there were 234.4 pieces/m2 of weeds; in the variant with fertilizer there were 186.9 pieces/m2, 20.3 % lower compared to the unfertilized background. The herbicides used on an unfertilized background (“Zellek Super” tank mixture, EC - 0.5 l/ha + “Galera Super 364”, VR - 0.3 l/ha) effectively suppressed the weed component - from 81.2 to 83.4 %. On a fertilized background, the effectiveness of herbicides was higher and varied from 92.4 to 94.3 %. The crops were treated against diseases after the first signs of Alternaria brassicae blight appeared on the lower leaves of the rapeseed. However, during the years of research, no further development of the disease was observed. As a result of the use of modern plant protection products against the background of nitrogen fertilizers, significant increases in the yield of spring rapeseed (0.23-0.58 t/ha) were obtained. Of the studied elements of the agricultural complex, the most significant factor was the application of nitrogen fertilizers, which ensured an increase in yield by 62.8 % without protective equipment. The maximum yield increase of 1.48 t/ha (112 %) was ensured by the use of complex protection against the background of nitrogen fertilizers.