Evaluation of interclonal elemental-profile variation in Sitka spruce seed.

Elemental profiles of seeds collected from four ramets in each of 10 clones growing in a 12-year-old Sitka spruce [Picea sitchensis (Bong.) Carr.] seed orchard were determined by X-ray energy-dispersive spectrometry. The data collected from the resultant spectra were used to assess differences among clones and among ramets of a single clone and to determine the mechanism governing the observed differences. The spectra were shown to be different from each other and were specific to each clone. Results from analyses of variance (ANOVA) indicated that the clonal differences accounted for the majority of variation (77%), while among ramets within clones differences rated second (17%). Broad-sense heritability estimates were highly significant and ranged from 0.46 to 0.95. The multivariate analyses conducted on the data further emphasized the results obtained from ANOVA and a high degree of success (90%) was achieved in classifying seed samples to their source clone. Results support the hypothesis that the elemental uptake and assimilation of minerals of Sitka spruce is under genetic control.