EFFECTIVENESS OF MINERAL FERTILIZERS IN CULTIVATING CANOLA FOR OIL SEEDS ON SOUTHERN CHERNOZEM

Abstract

The results of five-year research have shown that hydrothermal conditions of the growing season, especially, the amount of precipitation in July, play a crucial role in canola yield formation on southern chernozem in Northern Kazakhstan. In dry years (hydrothermic coefficient by Selyaninov in July < 0.4), oilseed gains from fertilizers did not exceed 0.15 t/ha, and as a result, only the use of nitroammophos in a dose of N20P20 was paid off without subsidies. In moderately wet years (hydrothermic coefficient in July is 1.0-1.5), oilseed gains increased up to 0.5-0.6 t/ha, and the use of phosphorus and nitrogen-phosphorus fertilizers was profitable regardless of a level of subsidies. The application of nitrogen fertilizer was ineffective regardless of the hydrothermal conditions of the growing season. It was established that moderately wet year’s water consumption by canola, as influenced by phosphorus and nitrogen-phosphorus fertilizers, decreased from 35 mm to 17-19 mm per 0.1 t of oilseeds.