EFFECT OF DIFFERENT MINERAL FERTILIZERS’ FORMS ON THE ABILITY OF THE NITROGEN ACCUMULATION, YIELD AND GRAIN QUALITY OF WHITE LUPIN

Improving of technique of fertilizers’ application at white lupin cultivation which aimed increase of symbiotic nitrogen accumulation, productivity and products quality is an actual task in solution of the problem of protein deficit. The tests have been done on light gray forest soils in the South-West part of the Non-Chernozem zone of Russia in Bryansk region in 2018–2020. The tests’ objects were white lupin variety Michurinskyi and fertilizers. Arable horizon had low humus content, high phosphorus content and increased potassium content. The tests’ results demonstrated the highest response of white lupin to the potassium application as the fertilizer Kaliy mag. The potassium in the dose 70 kg/ha as active substance resulted in increase of accumulation of dry plant mass and root system per a plant to the brilliant pod stage by 14.5 % and 57.4% respectively compared to the standard variant. In this case a part of the atmospheric nitrogen fixed by the white lupin is by 6.9 % higher at total admission compared to the standard. The yield increase level made 0.95 t/ha; raw protein content in seeds increased by 7.0 % compared to the variant free of fertilizers. The combined application of Kaliy mag as the main one and the complex fertilizer Aquarin on the green leaves enhanced the positive effect of this technique.The application of the fertilizers with the sulfur in their content had the positive effect on the ability of the nitrogen accumulation, productivity and products quality of white lupin.