The effectiveness of a number of morphophysiological traits as markers for the early selection (before 2 years) of conifer families is evaluated based on a number of retrospective studies involving primarily half-sib families. Traits discussed include height growth (with and without stress), shoot growth patterns, shoot–root ratio, nutrient and water use efficiency, gas exchange characteristics (including photosynthesis), injury indices, gibberellic acid levels, and metabolic efficiency. Taken singly, no one trait except height consistently predicts future field performance, but even height predictions, although reported for a number of species, are restricted to the performance of half-sib families. We propose that the prediction of future performance of full-sib or clonal families using height may be relatively more difficult, because genotype × environment interactions and maturational changes in growth behavior will decrease age–age correlations with increased genetic relatedness.
Estimation of genetic parameters and verification of early selection efficiency in baru (Dipteryx alata)