DOMESTIC POTATO VARIETIES YIELD UNDER THE FOOTHILL ZONE OF THE NORTHERN CAUCASUS CONDITIONS

The purpose of research is to identify domestic potato varieties adapted to the soil and climatic conditions of the foothill zone of the North Caucasus, combining high yields with resistance to pests and diseases in comparison with zoned varieties of North Ossetia. The studies were carried out in 2021–2022 at the experimental base of LLC Fat-Agro (Prigorodny District of the Republic of North Ossetia – Alania). The object of the study was 44 potato varieties of domestic selection of different maturity groups. Phenological observations, determination of biometric indicators of plants, quality and quantity of tubers, productivity, statistical processing of yield data were carried out according to generally accepted methods. Phytopathological monitoring of the resistance of potato varieties to the most common diseases was carried out by a visual method, evaluating each plant during periods of full germination at a plant height of 15–20 cm and flowering. The percentage of plants affected by diseases was calculated in relation to the total number. The highest yield on average over two years was obtained for varieties: in early ripe varieties – ZHukovskij rannij (38.3 t/ha), Vzryvnoj (37.7 t/ha), Krepysh (37.7 t/ha), Triumf (37.1 t/ha); mid-season varieties – Azhur (37.6 t/ha), Izyuminka (37.4 t/ha), Sineglazka (36.3 t/ha), Ryabinushka (40.2 t/ha); mid-late varieties – Alaska (42.2 t/ha), Rubin (31.7 t/ha) and Sorokinskiy (32.2 t/ha). All cultivars were resistant to wrinkled mosaic, with the exception of Musinskij (2.2 %), Rubin (7.2 %), Sorokinskij (4.5 %), Alyaska (1.0 %), Grand (1.0 %) ), Krasa Meshchery (1.0 %). The varieties Ariel and Triumf were the most resistant to mottled mosaic. All varieties of potatoes showed a high degree of resistance to late blight on tops and tubers. The manifestation of alternariosis ranged from 1.7 to 11.4 %.