GENETIC VARIANCE COMPONENTS FOR GROWTH VARIABLES OF Eucalyptus benthamii and E. smithii PROVENANCES CULTIVATED IN SOUTHERN BRAZIL

Abstract

Here we accessed the genetic variation for diameter at breast height (DBH), height (H), volume (VOL) and straightness of four provenances of Eucalyptus smithii and two of E. benthamii, cultivated in randomized block design in a farm in Rio Negrinho, Santa Catarina state, southern Brazil. We found considerable genetic variability for the traits under investigation, all directly associated with the selection for wood production and quality. The application of the REML/BLUP method predicted considerable genetic gains for the growth variables DBH, H and VOL for provenances and individuals of the two species. The highest genetic gains were predicted for a provenance of E. smithii originated from Australia (13% for DBH, 5% for H and 6.1% for VOL). However, the genetic gains from E. benthamii provenance from Santa Catarina state were not negligible (1.2% for DBH, 1.8 for H and 2.2% for VOL), especially if the top individuals were selected from BLUP estimates. Our results provide insights for further progeny trials aimed at investigating additive genetic variance and their components, which could improve the genetic control of the traits and assist breeding programs of E. smithii and E. benthamii.