Biological features of fruiting of various apple varieties in the Republic of North Ossetia-Alania

Abstract

The results of a long-term ecological testing of 12 apple varieties of domestic and foreign selection in the Republic of North Ossetia-Alania are presented. The biological features of fruiting of representatives of the genus Malus in a southern region of Russia were studied with the purpose of identifying the most valuable varieties in terms of a set of indicators for further breeding and production. According to the conducted long-term observations (2012–2019), the following varieties with compact small-sized crowns (volume of 1.48-2.09 m3) were identified: Zolotaya Korona, Lyubimoe Dutovoj, Sunrise and Red Chiff. Among summer triploid varieties, the variety of Soyuz was selected according to the yield factor (total yield was 159.2 t/ha, which was 56.5 t/ha higher than the control). The varieties of early winter and winter ripening period with a high total (198.3–299.2 t/ha) and average (33.05–49.87 t/ha) yield were determined: Ligol, Zolotaya Korona, Lyubimoe Dutovoj, Alanskoe and Pinova. It was established that the varieties of Alanskoe, Zolotaya Korona, Lyubimoe Dutovoj, Sunrise and Pinova exhibit high productivity indicators, with the specific productivity of the crown volume being 17.00–21.87 kg/m3. It was revealed that the fruits of all studied foreign and domestic apple varieties grown under favourable conditions of the region meet modern requirements in terms of diameter (65–75 + mm) and average weight (200–220 g). Among the most promising varieties for breeding and production were found to be Liberty, Zolotaya Korona and Lyubimoe Dutovoj with large fruit (214.5–237.8 g), as well as Soyuz, Ligol, Alanskoe and Prikubanskoe with very large fruit (289.3–330.2 g). It is concluded that the apple varieties of regional selection (Alanskoe, Zolotaya Korona, Lyubimoe Dutovoj, Soyuz) and foreign selection (Sunrise and Pinova) can be recommended when breeding varieties with the required set of valuable agrobiological propertites, as well as when creating intensive industrial plantings and obtaining high-quality domestic fruit products.