ABSTRACT:
Pinus radiata D. Don is the most widely planted exotic species in Australia, Chile, New Zealand and Spain. In this study, growth and survival of P. radiata were compared in 30 open pollinated families grown under two contrasting watering regimes in nursery (well-watered cf. water-stress conditions) and planted on a drought-prone site with Mediterranean climate in central Chile. This study assessed phenotypic plasticity in growth and survival at nursery stage and two years after establishment in the field. Family plasticity at nursery stage was estimated by the angular phenotypic change index (APCI), while the relationship between nursery and field traits was estimated by genetic correlations (rg) and the Pearson coefficient of correlation (rxy). Families presented high plasticity in diameter, height, and survival at nursery stage. Out of 30 families, eight exhibited over 80 % survival in the well-watered treatment, but less than 20 % survival in the water-stress treatment. As expected, growth traits and survival were positively correlated (rg and rxy > 0.65) between both nursery environments. However, for growth, most genetic and phenotypic correlations between combinations of nursery treatments versus the field test were negative or not significant. As there was no detectable pattern of nursery–field correlations regarding to combinations of nursery treatments and test site, the need to include more stable families and genotypes to an appropriate developmental stage at nursery is discussed.
Keywords:
Pinus radiata; survival; phenotypic plasticity; nursery-field correlations; dry sites
