Genetic Gain for Wood Volume in Progeny Trial of Grevílea (Breeding Cycle 2) in Avaré, State of São Paulo

Abstract

Twenty and twenty three seed provenances of Grevillea robusta A. Cunn. were imported from Australia, in 1993 and 1994, respectively, by Embrapa Florestas. This genetic germoplasm was utilized for starting a breeding program in the states of Paraná, São Paulo and Mato Grosso do Sul. In 2002, twenty eight genotypes were selected in the Presidente Castelo Branco-PR district whose seeds were utilized for the installing second generation progenies test in Avaré-SP. Randomized blocks was the statistical design utilized, with linear plots of five plants, adjusted in a compass 3m x 3m, with 8 replications. Total height, DBH (diameter at the height of breast) were the characteristics considered in the volume evaluations. Estimation of variance components, genetic parameters selection and genetic was made by SELEGEN/REML/BLUP - model 1. The conclusions obtained were: a) genetic gains were superior of 85%, remaining 227 genotypes (18% from the total amount of trees) in the Seed Orchard; b) selecting the best 50 genotypes, the genetic gain would be superior from 185%, and c) the installation of clonal orchard with the selected genotypes would lead a better spatial distribution of the clones, what wouldn´t happen in seed production areas originated of progenies installed in a randomized blocks design.