EFFECT OF FERTILIZATION SYSTEMS ON CORN YIELD ON LEACHED CHERNOZEM

In a long (since 1971) stationary field experiment it was found that mineral fertilizers and their combination with manure enhance growth processes: linear growth in height, the number of leaves, and the accumulation of dry matter increase. Of the fertilized variants the Manure + NPK and calculated variants had some advantage, accumulating more dry matter (60.4 and 56.2 %) with a control value of 43.9 %. The variants with a double dose of NPK and calculated had the maximum plant height (255 cm), exceeding the control by 30 cm, while the Manure + NPK variant was slightly inferior to them (253 cm). Fertilizers stimulated growth processes for a longer period of time than in the control. At the same time they did not differ from each other in the number of leaves (11 pcs.). As the cob mass increased, the fertilized variants accumulated more dry matter than the control - by 10.1-16.5 %. The highest accumulation was noted for the Manure+NPK variant – 60.4 %, inferior to it for the calculated (56.2%) and double dose of NPK (54.0 %). For all fertilized variants the yield exceeded the control: the increase in grain yield fluctuated within the range from 14.9 c/ha for a single dose of N1P1K1 to 29.0 c/ha for the calculated one. The maximum grain yield was obtained for the calculated dose – 73.3 c/ha with fairly high indicators of the yield formula. A comparison of the options for applying fertilizers in reserve for 3 years with the annual one showed the equivalence of both options – the yield was 60.2 and 59.1 c/ha, respectively (yield increase of 15.9 and 14.8 c/ha, or 35.9 and 33.4 %).