Influence of plant debris and fertilizers in crop rotation with oil crops on fertility of leached chernozem

«OIL CROPS» Scientific bulletin, VNIIMK, 2006, is 2 (135). The results of 22-year researches in stationary trial in grain rotation with oil crop are stated. An influence of plant debris of sunflower, castor, soybean, winter wheat and fertilizers on humus content, active form of phosphate and potassium in leached chernozem, on physical-chemical qualities, humus balance and nutrient elements.