Agrobiological and technological characteristics of wine grapevine cultivars from Dagestan
The agrobiological and technological characteristics of grapevine cultivars ‘Asyl kara’, ‘Platovskiy’, ‘Rubin Golodrigi’, ‘Saperavi’ and ‘Alyi terskii’ were assessed in order to collect data on adaptive behaviour of introduced species in the conditions of Dagestan, and determine cultivars with the best technological properties. Modern and standard methods were applied for agrobiologic registration and determination of technological properties of grapevines. The phenological observation data revealed differences in the full berry ripeness period of the studied cultivars (from 1 to 43 days) which confirms the ecological conditions impact of the cultivation place, and allows to rank cultivars by the following groups according to berry ripening dates: ‘Platovskiy’ in Dagestan demonstrated the potential of an extra early ripening period; ‘Asyl kara’ -early and medium, ‘Alyi terskii’ - medium, and ‘Saperavi’ and ‘Rubin Golodrigi’ - medium and late ripening period. Grapevine fertility is the principal indicator in assessment of the extent of grapevine adaptation to certain cultivation conditions. Thus, introduced cultivars ‘Asyl kara’ and ‘Rubin Golodrigi’ demonstrated high fertility (70-100 c/ha), ‘Platovskiy’, ‘Saperavi’ and aboriginal variety ‘Alyi terskii’ - very high fertility (over 100 c/ha). By cluster morphology, ‘Saperavi’ (27.6) and ‘Platovskiy’ (24.6) cultivars were the best. The high value of morphology indicator was demonstrated by ‘Rubin Golodrigi’ (16.2), ‘Alyi terskii’ (13.9) and ‘Saperavi’ (13.2). The latter were in the lead also by the structural indicator value (they stood out for a large amount of pulp with juice - 88-91% of the cluster weight, and low crest weight and solid residue), which is a valuable technological characteristic demonstrated by ‘Rubin Golodrigi’, ‘Saperavi’, and aboriginal grapevine ‘Alyi terskii’. Sugar and titratable acids content of all the studied cultivars were consistent with the requirements for wine cultivars. Data on positive manifestation of adaptive abilities of the studied cultivars in the conditions of the southern plain-piedmont zone of Dagestan are important for the formation of industrial assortment to ensure successful development of the viticinicultural industry of the agriculture of the Republic of Dagestan.