The effect of agroclimatic factors and indices of the Crimean Peninsula territory on the quality indicators of grapes

Abstract

The research uses long-term archive data on the content of mass concentration of sugars and titratable acids in grapes from Steppe, Piedmont and South Coast zones of the Crimean Peninsula. In order to identify the relationships between quality indicators of grapes and agroecological conditions of the area, territories with definite plots and grape varieties were selected for each zone. The selection criteria were: known date and place of harvesting, availability of meteorological data for this date and place. In the course of work we used indices recommended by OIV 423-2012 for terroir specialization in viticulture and winemaking industry. As a result, a correlation between the mass concentration of sugars and titratable acids in grapes, on the one hand, and a number of agroclimatic indicators and indices, on the other, was calculated. The study showed that the mass concentration of sugars in grapes had a positive correlation with different agroclimatic indicators in different natural zones of Crimea: South C ast zone (Otradnoye village) - with the sum of temperatures above 10 °C, Winkler index, hours of sunshine, precipitation per year, and growing season; Piedmont zone (Vilino village) - with sums of temperatures above 10 °C and 20 °C, Hooglin and Winkler indices; Steppe zone (Dzhankoy city) - no stable correlations were established, temperatures above 10 °C and precipitation a month before harvest had a negative effect. The content of titratable acids in ‘Muscat Blanc’ grape variety in the South Coast zone positively correlated with Hooglin index and precipitation, and negatively – with temperatures above 10 °C a month before harvest, cold nights index, and an average air temperature during growing season, as well as a month before harvest. In the Piedmont zone, a negative correlation with temperatures above 10 °C and 20 °C, Hooglin and Winkler indices was observed, and a positive correlation - with HTC. In the Steppe zone, a positive correlation between titratable acids and precipitation a month before harvest as established.