The productivity and quality of seed tubers of early ripe potatoes variety Severny at different terms and ways of planting in the northern forest-steppe zone of Tyumen region

The purpose of the researches was to fulfill elements of high-quality technology of cultivation of the variety Severny for seed purposes. The researches were con- ducted in 2012-2014 on experimental field of Agroinstitute of Technology of SAU of Northern Trans- Urals. The soil was lixivious chernozyom, heavy loamy on mechanical structure, is so-so provided with nutrition elements, the maintenance of humus - 7.2 %, the reac-tion of soil solution - 6.7. The predecessors were annu- al herbs on green material. The technology included dump plowing on the depth of 26-28 cm, spring harrow- ing, the incision of mineral fertilizers on the productivity of 50 t/hectare, cultivation on depth of 15-17 cm, the cutting of crests, planting in different terms: 10.05 (tem- perature of the soil +7 … +8 ° C), 20.05, 30.05, 10.06, 20.06, 30.06. The area of the allotment was 10 sq.m, the frequency 4-fold, randomized placement of allot- ments, the scheme of planting was 70 × 20 cm. It was established that as a result of 3 years' researches in northern forest-steppe zone of Tyumen Region in droughty and hot 2012 the productivity of an early ripe variety Severny at studied terms of planting was 1...