Physiological and biochemical responses to drought stress in some autochthonous grapevines of Turkey

Because of global climate change, the effects of drought stress, which is one of the important abiotic stress factors, are increasing. Therefore, breeding of grapevine cultivars is an important tissue to develop resistance to drought stress. In the present study, we investigated leaf relative water content (RWC), rate of water loss (RWL), membrane stability index (MSI), leaf pigment concentrations [chlorophyll (Chl) a, Chl b, carotenoids], lipid peroxidation (MDA), proline accumulation, and the activities of antioxidant enzymes [catalase (CAT) and ascorbate peroxidase (APx)] in some autochthonous grapevine cultivars ('Karabarcik', 'Manda Gozu', 'Bilecik Irikarasi', 'Horoz Karasi', 'Rumi', 'Tekirdag Seedless', 'Cavus', 'Trakya Ilkeren') in Turkey. Briefly, own-rooted autochthonous grapevines were subjected to drought stress for 7 days and then irrigated at field capacity for 2 days. Plant leaf samples were taken four times (0, 3, 7 and 9. days). Consequently, 'Horoz Karasi' and 'Tekirdag Seedless' exhibited relatively higher tolerance to drought, while 'Kabarcik' showed lower tolerance in response to severe stress. On the other hand, 'Horoz Karasi' and 'Kabarcik' exhibited better performance in the recovery phase.