Identification of the Origins of Lodgepole Pine Seeds by X-Ray Energy Spectrometric Determination of Mineral Profiles

Elemental profiles for 20 certified and one unknown sample of lodgepole pine ( Pinus contorta Dougl.) seeds from western north America (11 from Yukon Territory and 9 from British Columbia) were determined by X-ray energy-dispersive spectrometry. Three different multivariate techniques were performed on the spectral variables of each seedlot. Cluster analysis was used to explore any grouping among the different seedlots and to generate hypotheses about the nature of the clusters. The cluster analysis separated the northern and southern groups from each other and the unknown seedlot was correctly grouped with the nearest source seedlot. Results from the discriminant analysis confirmed the clear separation between the northern and southern groups. The provenance of origin of the unknown seedlot was successfully determined through the use of the derived discriminant function. Principal components analysis was used to generate synthetic composite variables which in turn were used in analyses of variance and correlation analyses. The analysis of variance allowed partitioning the total variation among three different levels, namely, between regions (north and south), among seedlots within regions and within seedlots. Clinal variation was demonstrated between the component scores and both latitude and longitude. The applications of this technique in forest seed certification are discussed. Forest Sci. 31:539-551.