The volatiles emitted from young and old leaves of two poplar clones (Populus deltoides x maximowiczii, Eridano, and P. x euramericana, I-214) were sampled after exposure to ozone (80 ppb, 5 hd−1, for 10 consecutive days) by solid phase microextraction and characterized by GCMS. Only mature leaves of the ozone-sensitive Eridano clone developed necrosis in response to ozone exposure, and their membrane integrity was significantly affected by ozone (+86 and +18 % of levels of thiobarbituric acid reactive substances in mature and young leaves). The headspace of the poplar clones studied here contained mono- and sesquiterpenes, both hydrocarbons and oxygenated ones in Eridano, and only hydrocarbons in the clone I-214. Furthermore, some non-terpenes, such as C9-C15 straight-chain aldehydes and C12-C16 saturated and unsaturated aliphatic hydrocarbons, were detected. Other common non-terpene volatiles were oxygenated aliphatic compounds, mainly C6-alcohols and their acetates. Ozone exposure induced a strong change in volatile profiles, depending on clones and leaf age. Regardless of leaf age, in clone I-214, quantities of oxygenated monoterpenes tended to increase after ozone exposure, however, “O3 x leaf age” was not significant. In clone Eridano, increases were observed in emissions of hydrocarbons and oxygenated sesquiterpenes in response to ozone treatment. (Z)-3-Hexen-1-ol and (Z)-3-hexenol acetate were present in traces in the headspace of untreated Eridano mature leaves, but quantities slightly increased after ozone treatment. Quantities of non-terpene oxygenated compounds dropped in the headspace of young leaves of both clones (−24 and −44 % in Eridano and I-214) and also in mature ones of I-214 (−50 %) after ozone exposure. Similarly, quantities of non-terpene hydrocarbons in the emissions from mature leaves of both clones (−58 and −49 %, respectively) decreased, while these compounds increased in young leaves of Eridano (+83 %). We suggest that the resistance of the poplar clone I-214 to O3 is achieved by: i) monoterpenes constitutively present in young leaves and ii) increase of monoterpene content induced by O3 in mature leaves.
|Autori:||Pellegrini E; Cioni PL; Francini A; Lorenzini G; Nali C; Flamini G|
|Titolo:||Volatiles emission patterns in poplar clones varying in response to ozone|
|Anno del prodotto:||2012|
|Digital Object Identifier (DOI):||10.1007/s10886-012-0162-2|
|Appare nelle tipologie:||1.1 Articolo in rivista|