Centro de Ecofisiologia, Bioquímica e Biotecnologia Vegetal/Instituto de Investigação Científica Tropical I.P., Quinta do Marquês 2784-505 Oeiras, Portugal.
J Plant Physiol. 2010 Mar 15;167(5):333-42. doi: 10.1016/j.jplph.2009.10.013. Epub 2009 Nov 24.
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.
低温（冷藏）通常与氧化应激条件的促进有关，对咖啡植物尤其重要，因为它对生长、发育、光合作用和产量有严重影响。然而，在咖啡属中已经报道了一些适应能力，可能与氧化应激控制有关。本研究采用综合生物化学和分子方法，对具有不同耐寒能力的基因型的抗氧化系统进行了表征。使用 1.5 年生的咖啡幼苗进行实验，包括 C. canephora cv. Apoatã、C. arabica cv. Catuaí、C. dewevrei 以及 2 个杂种，Icatu（C. arabicaxC. canephora）和 Piatã（C. dewevreixC. arabica），这些幼苗经历了逐渐的冷处理和恢复期。Icatu 表现出最强的控制氧化应激的能力，这反映在几种抗氧化成分（Cu、Zn-SOD 和 APX 活性；抗坏血酸、α-生育酚和绿原酸（CGAs）含量）的增强以及活性氧（H₂O₂和 OH）含量较低。基因表达研究表明，GRed、DHAR 和 III 类和 IV 类几丁质酶也可能参与了 Icatu 的耐寒能力。Catuaí 通过强化一些抗氧化分子表现出中等的适应能力，通常比 Icatu 观察到的要小。另一方面，C. dewevrei 在抗氧化剂积累方面表现出最差的反应，并且 OH 值的增加也最大。抗氧化特性触发的差异支持了其对咖啡属低温（和光抑制）耐受性的重要性假说，并可能为鉴定耐受基因型提供有用的探针。
