Ormeño Elena, Fernandez Catherine, Mévy Jean-Philippe
Institut Méditerranéen d'Ecologie et Paléoécologie (IMEP), UMR CNRS 6116, Equipe Ecologie Fonctionnelle, Université de Provence Centre de St Jérôme, Marseille, France.
Phytochemistry. 2007 Mar;68(6):840-52. doi: 10.1016/j.phytochem.2006.11.033. Epub 2007 Jan 26.
There is evidence that secondary metabolism may modulate plant interactions and is modified by different biotic stress agents, such as herbivores or pathogens. However, it is poorly understood whether secondary metabolism is altered during competition among plants. The intraspecific and interspecific coexistence of some Mediterranean potted seedlings, namely Rosmarinus officinalis, Pinus halepensis, Cistus albidus and Quercus coccifera was investigated through their terpene accumulation within leaves (except for Q. coccifera, a non-storing species) and terpene emissions (for all species). Competition had both positive and negative effects for both terpene emissions and content, depending on the species a seedling coexisted with. For R. officinalis, terpene concentrations (1.8-cineole and camphor) and terpene emissions (camphene, camphor and overall monoterpenes) were lower when the neighbour species was P. halepensis. For C. albidus, no changes were observed in its content, while the overall sesquiterpene emissions (70% of total emissions) were reduced in all competition conditions, except in intraspecific competition. In the case of P. halepensis, the highest terpene content occurred when it grew with C. albidus, and in intraspecific competition, while its emissions were reduced under these conditions. Only emissions of Q. coccifera showed no significant changes in the different competition treatments.
有证据表明，次生代谢可能调节植物间的相互作用，且会受到不同生物胁迫因子的影响而发生改变，如食草动物或病原体。然而，对于次生代谢在植物间竞争过程中是否会发生改变，人们了解甚少。通过研究一些地中海盆栽幼苗（迷迭香、阿勒颇松、白岩蔷薇和胭脂虫栎）叶片中的萜类物质积累情况（胭脂虫栎为非储存型物种，不做此项研究）以及萜类物质的释放情况（所有物种均进行此项研究），对它们的种内和种间共存进行了调查。竞争对萜类物质的释放和含量既有积极影响，也有消极影响，这取决于与之共存的物种。对于迷迭香而言，当相邻物种为阿勒颇松时，其萜类物质浓度（1,8-桉叶素和樟脑）和萜类物质释放量（莰烯、樟脑和总单萜）较低。对于白岩蔷薇，其含量未观察到变化，而在所有竞争条件下，除种内竞争外，其总倍半萜释放量（占总释放量的70%）均有所降低。对于阿勒颇松，当它与白岩蔷薇一起生长时以及在种内竞争时，萜类物质含量最高，而在这些条件下其释放量减少。只有胭脂虫栎的释放在不同竞争处理中未显示出显著变化。
