THE EFFECT OF GLYCOLURIL ON THE PRODUCTIVITY OF SPRING WHEAT (TRITICUM AESTIVUM L.)

The spring wheat Triticum aestivum L. var. Lutescens, Novosibirskaya-29 breed was taken for the investigation (the originator was Siberian Research Institute of Crop Research and Selection). Glycoluril (C4H6N4O2) is a slow-release nitrogen fertilizer (glycoluril assay was > 97 %), it was purchased from Glyoxal-T Ltd. The scheme of the field tests included control (no glycoluril used), application of glycoluril to soil (60 kg/ha), application of glycoluril to soil (90 kg/ha). Estimation of prolonged action of glycoluril on the wheat was carried out by superimposition of variants at the second year after application. To measure the photosynthetic and transpiration rates a portable infrared gas analyzer Li-6400 (LI-COR, Inc., USA) with opened system was used. The content of protein and fibrin in grains as well as their vitreousness were determined using Infralum FT-10 (Lumex Ltd., Russia). The chemical composition of the wheat herbage was determined in a wax stage according to Russian state standards (52838-07, 13496.4-93, 52839-07, 2622695, 26570-95, 13496.7-95). A positive effect of glycoluril on the productivity and quality of spring wheat grains was revealed. Local application of glycoluril to soil in doses of 60 and 90 kg/ha increased the crop productivity of wheat in the year of application by 22.5 and 26.8 %, respectively. An increase of the main parameters of nutritional value of wheat herbage, namely, increase in nitrogen content (up to 20.3 %), protein (up to 20.5 %), fibrin and leach (up to 11.1 %) as well as digested protein (up to 36.5 %) was found. This evidences on the accessibility of glycoluril by the plants at the year of application. Prolonged action of glycoluril at the second year after single application to soil was stated. The crop productivity raised from 16.5 to up to 25.1 %, photosynthetic rate by 39.2 - 40.8 %, stomatal conductance by 123.1 - 157.7 %, and transpiration by 38.2 - 42.1 %. An increase of protein content from 4.8 to up to 13.8 %, fibrin from 2.8 to up to 19.7 % and vitreousness by 6.0 % was found for all tests. Glycoluril has the strongest impact on the parameters of wheat productivity.