GENOTYPE BY ENVIRONMENT INTERACTION AND GENETIC CORRELATION OF GREENHOUSE AND FIELD PERFORMANCE IN PINUS-CONTORTA SSP. LATIFOLIA

Family by site interaction from 4 progeny test sites for 9-year height and its impact on estimation of genetic correlation between greenhous e traits and 9-year height were investigated in 110 families of Pinus contorta sap. latifolia from Alberta, Canada. Significant family by si te interaction, site and family effects were observed in 9-year height among 4 progeny test sites. The estimated narrow-sense heritability w as from 0.127 to 0.277 for individuals and was from 0.247 to 0.475 for family means. 25 greenhouse seedling traits (height, diameter, bud, b ranch and biomass) in 2 growing seasons were jointly studied with 9-ye ar tree height at the 4 progeny test sites. The genotype by site inter action had a significant impact on greenhouse-field family-means and g enetic correlations. Only 9-year tree height in the best site (site B) , which had more similar growing conditions to the greenhouse, had sig nificant family-mean and genetic correlations with greenhouse seedling traits. Seedling traits of height increment at the dormancy induction period between 2 growing seasons (HG1, r(g) = 0.52), height at the se cond growing season (H3, r(g) = 0.36), and height (r(g) = 0.37) and di ameter (r(g) = 0.42) at harvest, had the highest and g significant fam ily-mean and genetic correlation. The pattern of greenhouse-field fami ly-mean and genetic correlations among 4 sites indicates that early te sting should be conducted under simulated field conditions. The implic ations of genotype by site interaction on early selection were discuss ed for lodgepole pine.