Field crop rotations in organic agriculture of the Volgograd region

Soil fertility in biologized crop rotations depends on the saturation of them with legumes and sideral crops, perennial grasses, the involvement of grain crops in the organic matter cycle. The crop rotation was studied: 1) four-field grain and steam: clean steam - winter wheat - chickpeas - spring barley (control); 2) five-field grain and steam: occupied steam (clover green manure) - winter wheat - chickpeas spring barley - mustard + clover; 3) seven-field grain and grass: occupied steam (green manure oats) winter wheat - mustard - chickpeas - safflower dyeing - spring barley - sainfoin (hatcher field); 4) semi-field grass and grassland: occupied steam (phacelia green manure) - winter wheat - spring wheat - chickpeas grain sorghum - spring barley - alfalfa (hatchery field). The highest balance of organic matter was ensured in a five-field grain-steam crop rotation with clover for green manure +1.92 t/ha, in this crop rotation the highest balance was observed for nitrogen - +23.8 kg/ha and phosphorus - +1.3 kg/ha, grain harvest from 1 ha of arable land - 0.51 t/ha. The greatest balance of potassium was ensured in the seven-field grain and grass-crop rotation with facet on green manure - +8.8 kg/ha. The highest humus balance was observed in a seven-field grain-grass-crop rotation with oats per green manure - +0.12 t/ha.