Abstract

The aim of the research was to study the yield indicators of 36 early-ripening potato varieties in the northern region (Arkhangelsk) and the highlands of the North Caucasus (altitude 2500m above sea level). Experimental work was carried out in 2015–2020. Features of the northern zone - a light period of up to 21 hours in June - July, contributing to an increase in the duration of interphase periods of plant development. In the highlands, a short daylight hours of 14 hours, a sharp drop in daytime temperatures 15,1 – 25,8°С and night temperatures 7,8 – 15,2°С and intense solar insolation. Peat-podzolic-gley soils of the northern region are characterized by low humus (3,7%) and high - potassium (240 ... 267 mg/kg) in comparison with mountain meadow subalpine soils of high mountains (6,7% and 102 ... 120 mg/kg). Potatoes were planted in the first decade of June, harvesting - in early September. Was planted 25 tubers of each variety according to the scheme 0,7 × 0,3 m, the area of the accounting plot was 5.25 m². Using cluster, discriminant analyzes, the varieties were grouped according to a set of indicators: the multiplication factor, the yield of one plant and the average mass of tubers. In the northern region, the best were the varieties that formed from 8,1 to 11,4 tubers with an average weight of 37,0 ... 67,9 g and a yield of 400 ... 633 g. In the highlands, the varieties that formed 11,8 ... 19,8 pcs., 56,5 ... 70,6 g and 830 ... 1140, respectively, were the most productive. According to the results of the assessment of plasticity of 36 early-ripening potato varieties, they were resistant to extreme environmental conditions in northern and high mountains. zones were characterized by only five varieties: Daryonka, Red Lady, Breeze, Leader, Gulliver.

Key words: potatoes, variety, early maturity, field collection, Bank of healthy potato varieties, plasticity, northern zone, highlands.