dc.description.abstract | Genetic variation of tracheid length, specific gravity, latewood percentage,
height growth, and ring width among and within four provenances of tamarack (Larix
laricina (Du Roi) K. Koch) was investigated in a ten-year-old provenance test that
was planted in Thunder Bay, Ontario. Significant genetic variation of tracheid length,
height growth, and ring width was found among provenances and among clones
within provenances. A south-north trend of decreasing provenance means with
increasing latitude was found for tracheid length, height growth, and ring width. Fastgrowing
provenances generally had longer tracheids than slow-growing provenances.
Variation of specific gravity and latewood percentage was not significant among
provenances or among clones within provenances. Variance components and broad-sense
heritabilities of wood properties due to clones within provenances were larger
than those due to provenances. However, variance components and broad-sense
heritabilities of growth characteristics due to clones within provenances were smaller
than those due to provenances. Positive genetic correlations (r=0.03 to 0.88) between
wood properties and growth characteristics were detected, and the possibility of
improvement of both wood properties and wood volume in tamarack was discussed. | |