Selection of Eucalyptus clones for forest biomass and wood quality.

The genetic improvement applied to the Eucalyptus is an potential option to increase quality wood production; the knowledge of the variability and its expression is fundamental for the selection process and forest genetic improvement. The objectives of this work were: to estimate phenotypic and genetic parameters for growth characteristics and wood chemical and anatomical properties, to estimate genetic gains, and to select clones of Eucalyptus. Nine Eucalyptus clones, cultivated in the region of Taiobeiras, located at the North of Minas Gerais State, were analyzed. The experimental design was total randomized, with three repetitions. The phenotypic and genetic parameters were estimated by mean squares. For growth characteristics, chemical wood properties, width of the fibers and thickness of the cell wall, the effect of clone was significant. The predicted genetic gain for growth characteristics at the diameter at breast height were 12.00%, for total height was 6.91% and for individual volume, 24.92%. For chemical wood properties, the predicted genetic gains were: ash content, 25.72%; lignin content, 9.36%; and wood mass lignin, 33.46%. The predicted gain for fiber width and thickness of the cell wall were 7.87% and 13.86%.