Characterization of seeds from 10 IUFRO Sitka spruce provenances using trace element profiles as determined by X-ray energy-dispersive spectrometry

Abstract

Trace-element profiles for seeds collected from 10 International Union of Forest Research Organization provenances of Sitka spruce (Piceasitchensis [Bong.] Carr.) from the Pacific Northwest were determined by X-ray energy-dispersive spectrometry. Stepwise discriminant analyses were used to examine potential significant differences among groups and separate samples were used as unknowns to test each discriminant function. Three analyses were made, the first to discriminate among the 10 provenances, the second to discriminate among the five Canadian provenances only, and the third to discriminate the Canadian provenances grouped by soil types at provenance origin. Significant differences (P < 0.01) among groups were observed in all cases. High degrees of success were achieved in identifying "unknowns" and classifying them to their source groups (80–100%). Several variables were common among the three analyses, suggesting that the elemental profile of each provenance is a reflection of both environmental condition (soil chemistry) and the genetic makeup (mineral uptake). The use of this technique in forest seed certification is discussed.