Spectroscopic methods to measure heartwood stilbenes of Scots pine

Fast and accurate methods are needed to measure durability related chemical characteristics from solid wood. In the field of forest tree breeding the measurements would be performed from increment core samples collected from standing trees. In this study we have assessed the potential of Near Infrared Spectroscopy (NIRS) for evaluating the content of stilbenes (STB) pinosylvin (PS) and its monomethyl ether (PSM) from heartwood samples of Scots pine, Pinus sylvestris L. Gas chromatography mass spectrometry (GC-MS) was used as a reference method. Increment core samples originating from a Scots pine progeny trial were divided into calibration and validation sets. Predictive models were developed for the calibration set using partial least-square regression. Prediction accuracy of the models was evaluated using the validation set. The best model was characterized by a R² of 0.87 for the validation set, demonstrating the usefulness of NIRS for evaluating the content of stilbenes. Also a technology based on UV-fluorescence of stilbenes will be briefly discussed.