Economic and energy assessment of postcut and postharvest crops
Vetch-oat mixture, spring rapeseed and Sudan grass performed as objects of study. They were seeded after winter rye: two times - after the cut of green mass and once - after harvesting (factor A). Mineral background was factor B: no fertilizers, N<sub>16</sub>P<sub>16</sub>K<sub>16</sub>, N<sub>56</sub>P<sub>16</sub>K<sub>16</sub>. Sudan grass formed the highest green mass yield (10.6-23.4 t ha<sup>-1</sup>), vetch-oat mixture - the lowest one (5.8-9.4 t ha<sup>-1</sup>). The highest productivity happened at the first seeding, the lowest one - after harvesting. Fertilization improved significantly crop productivity. Rapeseed provided the highest payback (458%) at the first seeding, exceeding Sudan grass by 37% and vetch-oat mixture - by 195%. Mineral background decreased payback values. Second postcut seeding showed similar trends but payback of Sudan grass and rapeseed declined by 1.7-1.9 times. Vetch-oat mixture had the lowest production efficiency (14-34%). Postharvest cultivation of rapeseed was the most profitable. From the first postcut to postharvest seeding energy costs for production dropped: for vetch-oat mixture - by 32.5-46.1%, Sudan grass - by 42.72-58.6%, rapeseed - by 32.6-50.6%. Vetch-oat cultivation was energy-efficient only at the first seeding. Sudan grass and spring rapeseed had energy coefficient of above 1. The highest coefficient was obtained at the first seeding, the lowest one - after rye harvesting.