title: Biochemical and molecular characterization of the antioxidative system of Coffea sp. under cold conditions in genotypes with contrasting tolerance.
abstract: Low positive temperature (chilling) is frequently linked to the promotion of oxidative stress conditions, and is of particular importance in the coffee plant due to its severe impact on growth, development, photosynthesis and production. Nevertheless, some acclimation ability has been reported within the Coffea genus, and is possibly related to oxidative stress control. Using an integrated biochemical and molecular approach, the characterization of the antioxidative system of genotypes with different cold acclimation abilities was performed. Experiments were carried out using 1.5-year-old coffee seedlings of Coffea canephora cv. Apoatã, C. arabica cv. Catuaí, C. dewevrei and 2 hybrids, Icatu (C. arabicaxC. canephora) and Piatã (C. dewevreixC. arabica) subjected to a gradual cold treatment and a recovery period. Icatu showed the greatest ability to control oxidative stress, as reflected by the enhancement of several antioxidative components (Cu,Zn-SOD and APX activities; ascorbate, alpha-tocopherol and chlorogenic acids (CGAs) contents) and lower reactive oxygen species contents (H(2)O(2) and OH). Gene expression studies show that GRed, DHAR and class III and IV chitinases might also be involved in the cold acclimation ability of Icatu. Catuaí showed intermediate acclimation ability through the reinforcement of some antioxidative molecules, usually to a lesser extent than that observed in Icatu. On the other hand, C. dewevrei showed the poorest response in terms of antioxidant accumulation, and also showed the greatest increase in OH values. The difference in the triggering of antioxidative traits supports the hypothesis of its importance to cold (and photoinhibition) tolerance in Coffea sp. and could provide a useful probe to identify tolerant genotypes.
authors: Centro de Ecofisiologia, Bioquímica e Biotecnologia Vegetal/Instituto de Investigação Científica Tropical I.P., Quinta do Marquês 2784-505 Oeiras, Portugal.
authors: Ana S
authors: AS
authors: Fortunato
authors: Fernando C
authors: FC
authors: Lidon
authors: Paula
authors: P
authors: Batista-Santos
authors: António Eduardo
authors: AE
authors: Leitão
authors: Isabel P
authors: IP
authors: Pais
authors: Ana I
authors: AI
authors: Ribeiro
authors: José Cochicho
authors: JC
authors: Ramalho
mesh_terms: D000064:Acclimatization / Q000235:genetics / Q000502:physiology; D000975:Antioxidants / Q000378:metabolism* / Q000502:physiology; D060387:Ascorbate Peroxidases; D001205:Ascorbic Acid / Q000378:metabolism; D002109:Caffeic Acids / Q000378:metabolism; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D040503:Coffea / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D003080:Cold Temperature; D005838:Genotype; D018384:Oxidative Stress / Q000235:genetics / Q000502:physiology; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism; D016133:Polymerase Chain Reaction; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D024502:alpha-Tocopherol / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002109:Caffeic Acids; D017382:Reactive Oxygen Species; D010544:Peroxidases; D060387:Ascorbate Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase; D024502:alpha-Tocopherol; D001205:Ascorbic Acid; C040048:caffeic acid