Very early selection for solid wood quality: screening for early winners

Overview & Synopsis

This article reviews the theoretical basis for indirect selection - where early selection is an example - and how correlated response is calculated.* The review is followed by a description of issues as to the choice of selection criteria that could explain the lack of substantial progress on breeding for wood quality. These include: the autoregressive nature of selection criteria, overemphasizing the importance of basic density as selection criterion, ignoring age-related trends of wood properties, using rotation age rather than technical thresholds as objective traits and ignoring that not all grades have identical marginal economic value.* Three data sets are either analyzed for the first time or reanalyzed under different assumptions, to explore the importance of these criticisms.* Finally, the use of critical value thresholds as very early selection criteria is suggested and discussed in the context of improving intrinsic corewood quality.