Ramiro Daniel Alves, Guerreiro-Filho Oliveiro, Mazzafera Paulo
Centro de Café 'Alcides Carvalho,' Instituto Agronômico (IAC), CP 28, 13.020-902, Campinas, SP, Brazil.
J Chem Ecol. 2006 Sep;32(9):1977-88. doi: 10.1007/s10886-006-9122-z. Epub 2006 Aug 12.
We examined the role of phenolic compounds, and the enzymes peroxidase and polyphenol oxidase, in the expression of resistance of coffee plants to Leucoptera coffeella (Lepidoptera: Lyonetiidae). The concentrations of total soluble phenols and chlorogenic acid (5-caffeoylquinic acid), and the activities of the oxidative enzymes peroxidase (POD) and polyphenol oxidase (PPO), were estimated in leaves of Coffea arabica, C. racemosa, and progenies of crosses between these species, which have different levels of resistance, before and after attack by this insect. The results indicate that phenols do not play a central role in resistance to the coffee leaf miner. Differences were detected between the parental species in terms of total soluble phenol concentrations and activities of the oxidative enzymes. However, resistant and susceptible hybrid plants did not differ in any of these characteristics. Significant induction of chlorogenic acid and PPO was only found in C. racemosa, the parental donator of the resistance genes against L. coffeella. High-performance liquid chromatography (HPLC) analysis also showed qualitative similarity between hybrids and the susceptible C. arabica. These results suggest that the phenolic content and activities of POD and PPO in response to the attack by the leaf miner may not be a strong evidence of their participation in direct defensive mechanisms.
我们研究了酚类化合物以及过氧化物酶和多酚氧化酶在咖啡植株对咖啡潜叶蛾（鳞翅目：麦蛾科）抗性表达中的作用。在咖啡小爪螨攻击前后，对具有不同抗性水平的阿拉比卡咖啡、总状咖啡及其种间杂交后代叶片中的总可溶性酚和绿原酸（5-咖啡酰奎尼酸）浓度，以及氧化酶过氧化物酶（POD）和多酚氧化酶（PPO）的活性进行了测定。结果表明，酚类物质在对咖啡潜叶蛾的抗性中不发挥核心作用。在亲本物种之间，检测到总可溶性酚浓度和氧化酶活性存在差异。然而，抗性和敏感的杂交植株在这些特征上没有差异。仅在总状咖啡中发现了绿原酸和PPO的显著诱导，总状咖啡是抗咖啡潜叶蛾抗性基因的亲本供体。高效液相色谱（HPLC）分析还显示，杂交种与敏感的阿拉比卡咖啡在质量上相似。这些结果表明，响应潜叶蛾攻击时酚类物质的含量以及POD和PPO的活性，可能不是它们参与直接防御机制的有力证据。
