The mechanism of tolerance to high temperatures was investigated in two strawberry (Fragaria × ananassa Duch) cultivars, ‘Redlands Hope’ (‘R. Hope’, heat tolerant) and ‘Cal. Giant 3’ (‘CG3’, heat sensitive). Leaves were collected from plants that were exposed to gradual heat stress and heat-shock stress separately. | Turkish Journal of Agriculture and Forestry Turk J Agric For (2016) 40: 908-917 © TÜBİTAK doi: Research Article Effects of high temperature stress on enzymatic and nonenzymatic antioxidants and proteins in strawberry plants 1 2, 2 1 3 4 Sergül ERGİN , Hatice GÜLEN *, Müge KESİCİ , Ece TURHAN , Ahmet İPEK , Nezihe KÖKSAL Department of Agricultural Biotechnology, Faculty of Agriculture, Eskişehir Osmangazi University, Eskişehir, Turkey 2 Department of Genetics and Bioengineering, Faculty of Engineering and Natural Sciences, İstanbul Bilgi University, İstanbul, Turkey 3 Department of Horticulture, Faculty of Agriculture, Uludağ University, Bursa, Turkey 4 Department of Horticulture, Faculty of Agriculture, Çukurova University, Adana, Turkey 1 Received: Accepted/Published Online: Final Version: Abstract: The mechanism of tolerance to high temperatures was investigated in two strawberry (Fragaria × ananassa Duch) cultivars, ‘Redlands Hope’ (‘R. Hope’, heat tolerant) and ‘Cal. Giant 3’ (‘CG3’, heat sensitive). Leaves were collected from plants that were exposed to gradual heat stress and heat-shock stress separately. The contents of nonenzymatic antioxidants such as ascorbic acid (AsA) and glutathione (GSH) and the activities of enzymatic antioxidants such as ascorbate peroxidase (APX) (EC ), catalase (CAT) (EC ), and glutathione reductase (GR) (EC. ) were measured followed by heat treatments. Additionally, proline content was determined, and heat shock proteins (HSPs) were analyzed with an immunoblotting method to investigate protein markers involved in the heat-stress tolerance of strawberry plants. The contents of AsA and GSH did not change depending on heat stress type, temperatures, or cultivars. While APX and CAT activities increased with high temperatures, GR activity was almost unchanged. The proline content of the cultivars .
