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General Prediction Model for Age-Age Genetic Correlations in Pinus taeda

In long rotation crops such as forest trees, traits are rarely measured at all ages up to harvest age. Therefore, modelling of age-age genetic correlations is essential for predicting optimum selection age. Using data from four progeny tests of Pinus taeda planted in Zimbabwe assessed up to rotation age for height at 1.5, 9.5, 13.5, and 22.5 years, a tropical prediction model for age-age genetic correlations was derived (Gwaze et al. 1996, rg = 0.98 + 0.065 loge (younger age/older age)). This model was significantly different from phenotypic models such as Lambeth's (Lambeth 1980). The tropical model was tested using data from twenty genetic tests of P. taeda from south eastern USA, assessed at 3, 5, 8, 10, 15, 17, 20 and 25 years (Table 1). The tests were located in Arkansas, Georgia, Louisiana and Texas. Possibilities of developing a general prediction model for P. taeda based on age-age genetic correlations were explored.


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Author(s): David P. Gwaze, Floyd E. Bridgwater, Thomas D. Byram, Claire G. Williams, J. A. Woolliams

Publication: Tree Improvement and Genetics - Southern Forest Tree Improvement Conference - 1997

Section: Contributed Presentations: Extended Abstracts