ECOLOGICAL FACTORS OF THE NORTHERN REGION AND HIGHLAND ZONE INFLUENCE ON YIELD FORMATION OF EARLY MATURING POTATOES VARIETIES

Abstract

The aim of the research was to study the yield indicators of 36 early maturing potato varieties in the northern region (Arkhangelsk region) and the highlands of the North Caucasus (an altitude of 2500 m above sea level). The experimental work was carried out in 2015–2020. The characteristic features of the northern region are the light period (up to 21 hours in June – July), 
 which contributes to an increase in the duration of the interphase periods of plant development, in the highlands – a short light period (14 hours), a sharp temperature drop in the daytime (15.1 – 25.8 °С) and night (7.8 – 15.2 ° C) hours, intense solar insolation. The peat-podzolic-gley soils of the northern region were characterized by a lower humus content (3.7%) and a high content of potassium (240 – 267 mg / kg) in comparison with the mountain meadow subalpine soils of the highlands (6.7% and 102 – 120 mg / kg, respectively). Potatoes were planted in early June and harvested in early September, 25 tubers of each variety according to the scheme 0.7×0.3 m, the area of the registration plot was 5.25 m². Using the methods of cluster and discriminant analyzes, the varieties were grouped and the most productive genotypes were identified by a set of indicators: the multiplication factor, plant productivity and the average tuber weight. In the northern region, the best varieties were Gulliver, Udacha, Krepysh, Solist, Leader, Darenka, Breeze, Red Lady, Riviera and Vineta, which formed from 8.1 to 11.4 tubers per plant with an average weight of 37.0 – 67.9 g and productivity 400 – 633 g. In the highlands, the most productive varieties were Gulliver, Yakutyanka, Yugana, Darenka, Leader, Breeze, Red Lady, Impala and Rosara, which formed from 11.8 to 19.8 tubers per plant with an average weight of 56.5 – 70, 6 g and productivity 830 – 1140 g.