Avaliação do crescimento inicial de dois clones de eucalipto em argissolo amarelo no estado do Maranhão

Abstract

The presente, work aimed to evaluate the initial growth of two eucalyptus clones on the same soil class. The experimental plots are located in a leased area used by the Suzano pulp and paper company, in the region of São Pedro d'água Branca, in the state of Maranhão. The planting area has 3x3 spacing, and the experiment was allocated in 15x15 experimental plots, with evaluation of the 25 central plants, to avoid the edge effect. The study comprised a total of 4 plots in the two studied areas with a total of 600 evaluations in the 3 periods. The data were evaluated through statistical analysis of significance, analysis of diametric distribution and average increment in diameter and height. The clones used in the experiment were operational clone 1 and semi-operational clone 2, planted in large and small scale, respectively. In the statistical analysis, it was found that the clones are statistically different from each other for the diameter and height variable. The growth rates for clone 1 and 2 in the diameter variable, were 0.1455 and 0.1542 respectively. The growth rates for clone 1 and 2 in the height variable, were 0.7991 and 0.7996 respectively. For both variables, clone 2 was statistically better. In the analysis of diametric distribution, it was observed that, in the three evaluations, clone 2, obtained most of its individuals concentrated in the centers of intermediate class of diametric mean. For the evaluations of mean diameter increment, clone 1 showed a similar mean to clone 2. The two clones showed no significant differences in relation to average diameter increment. In the evaluations of average height increment, it was found that clone 1 obtained an average of 29.60 in the last evaluation, but the clones showed no statistical differences for height increment. Despite the statistical differences between the two clones, the results showed a similar performance for both clones in the periods evaluated.