GENOTYPES X ENVIRONMENTS INTERACTION FOR PRODUCTIVITY OF Eucalyptus L'Her. CLONES IN THE STATE OF RIO GRANDE DO SUL, BRAZIL

The present study aimed to study the genotypes interaction in environments of Eucalyptus clones, in four environments in the state of Rio Grande do Sul. The tests were conducted in the areas of company CMPC Celulose Riograndense, in the municipalities of Minas do Leao (farm Cambara), Encruzilhada do Sul (farm Capivara), Dom Feliciano (farm Fortaleza) and Vila Nova do Sul (farm Sao Joao). In 2007, a network of clonal tests was implanted with 864 clones of Eucalyptus, belonging to 37 different species and hybrids. At three years of age, we measured the diameter at breast height (dbh) and total height (Ht) of the trees of the experiments. The mean annual increment (MAI) was calculated according to the individual volume per clone and plant stand in hectare at age of evaluation of clonal test. The results for the genotypic correlations among environments ranged from 0.39 to 0.56, showing that there was significant genotype x environment interaction for all the evaluated characteristics. These results indicate that it is necessary to select specific clones for combinations of environments with low genetic correlation between them. Low genetic correlation occurred between cambara x capivara; cambara x sao joao; capivara x fortaleza; capivara x sao joao; and fortaleza x sao joao. Thus, for this study three management units were necessary to minimize the effects of genotypes x environments interaction. Including selection for stability, adaptability, and both attributes simultaneously, there was a change between clones and the position of the clones in the order of selection. With the simultaneous selection for stability and adaptability (MHPRVG), the gains increased compared to the selection for predicted genotypic values among environments, especially; and there was an increase in gains compared to the commercial control. For example, the five best clones according to the criterion MHPRVG are 56% higher than the commercial control for the characteristic productivity in volume.