Terpene attractant candidates of Dioryctria sylvestrella in maritime pine (Pinus pinaster) oleoresin, needles, liber, and headspace samples
Résumé
Capillary GC analysis was used to determine the proportion and quantity of terpenes in wood resin, pentane extracts from needles and liber, and headspace samples of needles and pruning wounds in 24 thirteen-year-old maritime pine. Fifteen different terpenes were identified in the samples. Germacrene D and β-pinene were the dominant terpenic compounds in the needles, while α-pinene and β-pinene were dominant in the liber and wood resin. Headspace samples of both needles and pruning wounds contained essentially monoterpenes. Only trace amounts of sesquiterpenes were found in pruning wound emissions. The presence of an oxygenated compound, linalool, in the pruning wound emissions is discussed, although this compound is not found in Maritime pine essential oil. Twelve of the 24 trees studied were infested by Dioryctria sylvestrella. Maritime pine susceptibility to this insect was related to the terpene composition of the different samples.