Studies of white - Engelmann spruce genetics

Project number: EP 670.71

Districts: Rocky Mountain and Selkirk Forest Districts

Objectives

• To estimate the accuracy of open pollinated progeny trials as a measure of general combining ability
• To estimate and compare the specific combining abilities both within and among geographically distant populations
• To compare the magnitudes of GCA and SCA and determine the most attractive mating design in terms of realized gain
• To obtain more reliable estimates of heritability and genotype X environmental interactions, and evaluate the potential of farm field trials for future full-sib progeny trials
• To evaluate the adaptability of various combinations of inter-population crosses

Treatment

Four breeding units were assembled with each breeding unit comprised of grafted clones of 10 parent trees representing geographically distinct populations of white and Engelmann spruce. The PG, EK and PR breeding units were assembled by selecting families ranked in the upper 75%. Five of the trees are ranked in the top 25%. The eastern North American trees were selected on the basis of the growth rate of their grafted ramets and flowering potential.

The crossing program consists of half diallel crosses with reciprocal crosses within each breeding unit and disconnected partial factorial crosses among breeding units. The resulting seedlings were grown at the Riverside nursery in Armstrong.

Layout

• Each site contains five blocks
• A row of four seedlings represents one cross
• Crosses are randomized within each block
• The first seedling of each row is marked with a wooden stake bearing a metal tag identifying the block and the family

History

• 1989 plantation establishment and initial height measurements
• 1990-1995 annual height measurements and maintenance
• 1998 tenth-year height measurements and maintenance
• 2001 maintenance