Peñuelas Josep, Llusià Joan
CSIC-CEAB-CREAF Ecophysiology Unit, CREAF (Center for Ecological Research and Forestry Applications), Edifici C, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain.
Trends Ecol Evol. 2004 Aug;19(8):402-4. doi: 10.1016/j.tree.2004.06.002.
All plants emit substantial amounts of phytogenic volatile organic compounds (PVOCs), which include alkanes, alkenes, alcohols, aldehydes, eters, esters and carboxylic acids. Defence, communication and/or protection against extreme conditions have been proposed as reasons for these emissions. However, Rosenstiel and colleagues have recently proposed that emission of PVOCs represents a metabolic 'safety valve' by preventing the unnecessary sequestration of phosphates. Additionally, Niinemets and colleagues suggest that the emission rates of some PVOCs are determined by the principal physicochemical characteristics of the emitted compounds, such as their solubility, volatility and diffusivity, rather than by physiological mechanisms, such as their synthesis rates. These two new studies lead to the hypothesis that there is not necessarily a specific role for every PVOC emitted, given that their emission is unavoidable as result of their volatility. However, in some cases, natural selection has worked to take advantage of this volatility.
所有植物都会释放大量的植物源挥发性有机化合物（PVOCs），其中包括烷烃、烯烃、醇类、醛类、醚类、酯类和羧酸。人们认为这些排放物的原因是防御、通讯和/或抵御极端条件。然而，罗森施蒂尔及其同事最近提出，PVOCs的排放是一种代谢“安全阀”，可防止磷酸盐被不必要地螯合。此外，尼内梅茨及其同事认为，某些PVOCs的排放速率取决于所排放化合物的主要物理化学特性，如溶解度、挥发性和扩散性，而非生理机制，如合成速率。这两项新研究提出了一个假设，即鉴于PVOCs因其挥发性而不可避免地排放，并非每种排放的PVOC都一定有特定作用。然而，在某些情况下，自然选择已利用了这种挥发性。
