Investigation of the Phenological and Climate Indices of Some Table and Wine Grapes and Their Growing Status in the Samsun-Bafra Plain (Türkiye)

Abstract

The aim of this study was to determine the viticultural potential of Bafra plain based on viticulture climate indices. Bafra district was classified as warm-temperate according to Winkler and Huglin indices. The Winkler index (WI) 1969.0, Huglin index (HI) 2184.4 °C units, Branas Heliothermic Index (BHI) 4.5, and Branas Hydrothermal Index (HYI) 3423.6 were obtained for the Bafra region. Annual sunshine duration was calculated as 2295.5 hours, while sunshine duration during the growing period was 1715.0 hours. Considering the HYI value being somewhat high, this combined with the high air humidity in the summer months shows an increased risk of fungal diseases. The bud burst occurred in the second week of April and flowering occurred in the first week of June in all cultivars. The earliest veraison initiated with early ripening ‘Early Sweet’ and ‘Trakya İlkeren’ cultivars and the latest veraison was in ‘Ugni Blanc’ and ‘Red Globe’. The earliest ripening was determined in ‘Early Sweet’ with 937.7 GDD, and the latest ripening was determined in the ‘Ugni Blanc’ cultivar as 1729.2 GDD. The period from bud burst to maturity was 110 days in ‘Early Sweet’ and 170 days in the ‘Ugni Blanc’. Sites selected with high altitude, areas that slope slightly to the south sides, low humidity, and far from sea areas are suitable for early and mid-season ripening grape cultivars. The high humidity in the summer and heavy rain in the fall season increase fungal disease risks in the Bafra region.