Chemical analysis of methyl jasmonate-treated and weevil-damaged pine seedlings using GC-MS and LC-MS

In my PhD work I analyze conifer constituents that seedlings produce and emit into the environment. The aim is to identify chemical resistance markers in Scots pine Pinus sylvestris against the large pine weevil Hylobius abietis. This insect is one of the economically most important forest pests in Sweden and almost 90% of the seedlings could die without protective measures such as shelterwood and soil scarification (1). Insecticides add to the protection of the seedlings but the future prohibition call for replacement. Aiming to explore the role of induced defences in pine resistance to this weevil we analyzed the chemical responses of pine seedlings to weevil damage and to the application of methyl jasmonate, a signal hormone that, exogenously applied, mimicks insect herbivory (2,3). Based on biological results from greenhouse trials in Sweden and in Spain, I evaluate stress responses from seedlings using GC-MS and LC-MS. From this I have found induction of ß-pinene in Scots pine (Pinus sylvestris) after pretreatment with methyl jasmonate, and in Maritime pine (P. pinaster) and Monterey pine (P. radiata) after pine weevil infestation. The induction is observed in both stem and needles. Further I investigate possible activation of the (-)-pinene-synthase using chiral analysis with 2D-GC-MS.
The research is supported by the Swedish Foundation of Strategic Research