ABSTRACT
Few species of Eucalyptus are considered useful for forestation in arid zones. Eucalyptus cladocalyx is one of them, and it has been regarded in inter-specific hybrid programs for improvement characteristics like drought tolerance. 49 half-sib families from six populations were evaluated 30 months after the plantations in two localities of Chilean semiarid: Caracas and Tunga. Each trial was a randomized complete blocks design, with single tree plots and 30 blocks. Variance components were estimated by restricted maximum likelihood (REML) method in a mixed linear model. Predicted genetic values for origin random effect ware obtained by the use of best linear best linear unbiased predictor (BLUP). Although heritability was calculated using k coefficient equal to 2.5, heritability values of height were moderated and high, with values from 0.48 in Caracas to 0.76 in Tunga. Heritability values for basal diameter were moderated, varying from 0.26 to 0.39 in Caracas and Tunga, respectively. The origins of Cowell, Remarkable and Illapel showed negatives genetic values in both sites. Wirrabara provenance has always obtained superior genetic values, showing to be an interesting provenance for improvement program of this species. If heritability values remain in the time, they will allow genetic gains and the improvement of Eucalyptus cladocalyx plantations productivity.
Keywords:
variance components; mixed models; arid zones