Abstract:

This study was carried out in a 12-year-old progeny test of open-pollinated Larix kaempferi families in Jianshi County, Hubei Province. The correlation, path analysis and indirect selection among growth, form and wood properties were analyzed. According to selection indices, a number of superior families with fast-growth, good stem-form and high wood qualities were selected for the pulpwood purpose in the subtropical alpine region of China. Finally, breeding procedure for pulpwood and utilization strategies of selected families were suggested. Main conclusions from the study were showed that: Correlations between growth traits and fiber length were positively high, and wall/lumen were negatively high, and basic density, 1%NaOH extract and holo-celouse were insignificant. Correlations between basic density and main-branch length, between fiber length and main-branch length, main-branch diameter, fresh-branch diameter, between wall/lumen of late wood and main-branch length, main-branch diameter, bark thickness, crown width, fresh-branch number, between 1%NaOH extract and main-branch length were positively high. Path analysis of nine traits, which were highly correlated with tree volume, showed that the direct contribution of DBH and height on the variations of tree volume took up about 63% of the total variations. On the other hand, those traits, such as tree crown and wall/lumen, affected the volume strongly by indirect way of the genetic correlation with DBH and height. The controlling system comprised of 9 traits could explain 98.66% of variation of the individual tree volume.

Key words: Larix kaempferi, open-pollinated family, pulpwood properties, growth traits, stem-form traits, index selection