Eco-physiological responses of ‘Campbell Early’ and ‘Jinok’ grape vines of two regions affected by different climatic conditions

Abstract

This study was performed to evaluate vine performance, physiological disorders of the berries, and disease of two grape (Vitis labrusca) cultivars, ‘Campbell Early’ and ‘Jinok’, in response to climate changes in private vineyards of two different latitudes, the Naju region (35°N) and the Okcheon (36°N) region, between the years 2016 and 2018. The climates from April to August or during the period of berry ripening (July and August in 2016–2018 in the Naju region was warmer than that of the 10-years average, causing approximately a 10-day longer duration of leafing to harvesting than during 2011 and 2012 for ‘Campbell Early’ vines. Total shoot length was the highest for both grape cultivars grown in Naju vineyard, when temperatures ranged between 20 and 25 °C from April to June, resulting in increased yield of ‘Campbell Early’ vines. Severe cracking of up to 59.1% of ‘Campbell Early’ berries occurred in the vineyard in Okcheon in 2017 when a high amount of precipitation occurred during the period of ripening. Also, an incidence of berry blight occurred on up to 30.6% of berries in ‘Campbell Early’ vines in the vineyard in Naju in 2018, which was subjected to a mean daily maximum temperature of 33.6 °C. Mean daily maximum temperature and number of heatwave days during the ripening period were positively related to the occurrence of berry cracking over the three years of this study, with a significant correlation observed between precipitation and mean temperature and berry blight. Downy mildew and powdery mildew occurred on both grape cultivars in the vineyard in Naju over the three years, with severe leaf spot observed on both cultivars in the region.