Untitled

Abstract

Pine weevils (Hylobius abietis) fed less on bark of lodgepole pine (Pinus contorta) than on bark of Scots pine (P. sylvestris). Two pine weevil antifeedants, ethyl trans-cinnamate and ethyl 2,3-dibromo-3-phenyl-propanoate, were isolated from bark of lodgepole pine. These two compounds significantly reduced pine weevil feeding in a laboratory bioassay. In field assays, the second compound significantly decreased pine weevil damage on planted seedlings. Ethyl 2,3-dibromo-3-phenylpropanoate has not previously been reported as a natural product.

Damage by the pine weevil <i>Hylobius abietis</i> to seedlings of two native and five introduced tree species in Sweden

“…In the present study the mean debarked area did not differ between Norway spruce and Scots pine seedlings, but significantly more feeding damage was found on Sitka spruce, showing that there are also differences within the genus Picea. The pine weevil consumed less bark on lodgepole pine than on Scots pine seedlings, possibly because antifeedant compounds that have been identified in lodgepole pine but not in Scots pine influence weevil feeding preferences (Bratt et al 2001). Several field and laboratory experiments have also shown that larch is a less attractive food source than Norway spruce and Scots pine (Löf et al 2004;Olenci and Olenci, 2003), and billets of Sitka spruce reportedly attract more pine weevils than larch billets (Wilson and Day 1995).…”

“…However, in that experiment, the native species reportedly had higher tolerance to the damage. The differences between tree species in the extent of feeding damage are probably related to variation in chemical composition, influencing the quantity of phloem tissue consumed by the pine weevil (Bratt et al 2001;Carillo-Gavilán 2012;Moreira et al 2013). Induction of resin in the stem and phloem after wounding as well as nitrogen concentration has been found to vary between tree species, and may contribute to variation in the amount of pine weevil feeding (Wainhouse et al 2004;Zas et al 2011).…”

“…However, since the demand for short-rotation plantation is increasing and hybrid aspen has proved to be one of the fastest growing deciduous tree species (Tullus et al 2012) and therefore highly interesting for biomass production it is important to determine the level of damage caused by pine weevils to this tree species. Pine weevil feeding preferences among a number of different conifer species have mainly been investigated under laboratory conditions, and cut-off twigs or seedling stems have usually been used instead of living trees or seedlings (Leather et al 1994;Manlove et al 1997;Bratt et al 2001;Olenici and Olenici 2003;Månsson and Schlyter 2004). This may give misleading results, since defence mechanisms may be induced in living seedlings that could strongly influence both feeding preferences and the amounts of bark consumed (Zas et al 2011).…”

Hydroxy-Methoxybenzoic Methyl Esters: Synthesis and Antifeedant Activity on the Pine Weevil, Hylobius abietis

“…Because of environmental hazards and health risks for forest workers the usage of insecticides is seriously questioned today. Possibly, antifeedant substances applied to transplants could offer an alternative to insecticides [2].…”

Antifeedants Produced by Bacteria Associated with the Gut of the Pine Weevil Hylobius abietis

“…To confirm the pine weevil antifeedant activity of the three major compounds identified in the emissions of isolated bacterial isolates, feeding tests were made by means of a two-choice laboratory bioassay, used in several previous studies [10, 12–15, 27]. 2-Phenylethanol and 2-methoxyphenol were tested in the concentrations 5, 25, and 50 mM, while for phenol only 50 mM was used.…”