Parâmetros genéticos e índice de seleção para caracteres de crescimento e tecnológicos em Eucalyptus spp. em áreas de diferentes altitudes

Abstract

This study aimed to analyze the selection comparing predicted genetic gains for the variables Height, Diameter at breast height, Basic Density, Purified Yield, Effective Alkali, Wood Volume and Cellulose Weight for Eucalyptus spp. from the Rio Doce Valley region, in the city of Pingo d´Água - MG, planted in two different environments - lowland flat terrain (area 1) and sloping terrain (area 2). 112 families were used and the families were defined through specific crossing with known father and mother. Measurements were taken at 3 years of age. The design used was randomized blocks, divided into 5 blocks containing 8 families per block. Height averages were performed using a inclinometer and chest height diameter with tape measure. The basic density was measured using the pilodyn equipment and the yield purified using NIR (near infrared). Exploratory data analysis and analysis of variance (ANOVA) were performed in the Genes program, estimation of genetic parameters in Selegen, and from this comparison the selection methods were compared by combined selection analysis in the Genes program. It was possible to observe that the population of area 2 presented higher values in the means of the variables, as well as the genetic parameters demonstrating the superiority of this population in relation to area 1 for wood and pulp productivity traits. It was possible to select the best individuals and thus obtain by the REML / BLUP method knowledge of which species can be chosen to result in clones with characters most desirable for the industrial sector. The crosses between the species E. urophylla, E. grandis and E. tereticornis were the ones that contributed to the greatest genetic gains among the studied characteristics. It is recommended to assemble a new crossing matrix with only the best parents identified in this study, in order to obtain a population with better mean values than those obtained in this population.