The Nectariy grape cultivar for the northern zone of Russian industrial viticulture

Abstract

The domestic assortment of fruit and berry crops should include new varieties with high biological plasticity, group resistance against adverse environmental conditions, different ripening duration, and sufficiently high quality of the final products. These requirements are highly relevant in grape breeding. Nektariy, a new grape сultivar of interspecific origin, was admitted to state testing in 2021. This cultivar was created at Y.I. Potapenko All-Russian Research Institute of Viticulture and Winemaking under the state task for cultivation in the northern zone of industrial viticulture of Russia and for production of high-quality Muscat wine of various types. The studies were carried out according to conventional ampelography methods. The Nektariy agrobiological characteristics include the following: a cultivar of industrial purpose with an early ripening period. During the 2018–2022 period, the production period lasted, on average, 115 days under the effective heat sum of 2501°C. Nektariy is characterized by high winter hardiness and the budburst percentage from 84 to 100. Under the negative temperature sum of 586°C and the absolute minimum temperature of minus 24.6 °C, 49 % of live buds was registered. The number of fruiting shoots comprised 90–98 % under the fruiting coefficient of 1.4. On average, the yield per plant was 5.9 kg on a single-plane trellis under the planting scheme of 3×1.5 m. The cultivar ampelographic description is as follows: androgyne flower, cylindro-conical bunches of medium density weighing on average 153 g. The knot is very short, green, sometimes woody, green ridge. The berry is rounded, greenish-yellow, with an intense pruinous stain, with an average weight of 1.9 g. The flesh is juicy with a muscat aroma. In order to create a passport of the cultivar, the Nektariy leaf blade was measured in terms of 33 parameters using the SIAMS Mesoplant soft ware for analyzing the morphology and structure of plants. This cultivar is characterized by a high accumulation of sugars up to 29.3 g/100 cm3 under a moderate acidity of 5.8 g/dm3 . The resistance to major fungal diseases is high, which allows this cultivar to be used in breeding as a donor of resistance genes to mildew. The shoot growth strength is medium; shoots mature well. The affinity with rootstock varieties is high. The tasting score of dry wine and liqueur wine averages 8.65 and 8.8 points, respectively, on a ten-point evaluation scale. The cultivation of Nektariy grape is economically efficient due to low expenditures associated with uncovered cultivation and disease protection measures. Nektariy is used for the production of high-quality Muscat wine with the profitability 140 %. Nektariy is recommended for uncovered cultivation in wine-making Russian regions with an absolute minimum of winter temperatures up to minus 26 °C.