Combining genetic gain and diversity under an individual selection method in a selected provenance of Eucalyptus cladocalyx

Abstract

Flowering traits are becoming important breeding objectives in Eucalyptus cladocalyx. Previous studies have confirmed that the trees from Cowell, Australia, respond well for early flowering under the arid conditions in the Southern Atacama Desert, Chile. This selected population was evaluated for flowering intensity at the end of the flowering season of 2009/2010 (February 2010). A Bayesian threshold tree model via Gibbs sampling was used in the data analyses. The model included the genotype-environment interaction (two sites) using a bi-character threshold model. The posterior mean of the genetic correlation between the sites was positive and high (r=0.8) and, according to the 95% credible interval (0.44–0.96), it was significantly different from zero, indicating a non-significant interaction. The intensity of selection should be close to 11% to balance the gain and diversity after the individual tree selection in this breeding population.