Seleção de genótipos de Eucalyptus spp. cultivados no estado do Mato Grosso para suprimento de lenha para as agroindústrias

Abstract

The expansion of agribusiness in recent years has resulted in the growth of bioenergy use in the agricultural sector, mainly in the production of soybean and corn, sectors that have been highlighted in national production, and, together with this, the installation of industries that use bioenergy, provided a new opportunity for the forestry sector, where, the state of Mato Grosso stands out. Three individuals were selected for eleven different genetic materials, which totaled 33 sample materials aged eight years, from the clonal test located in Tangará da Serra - MT. The mean values in the percentage of bark ranged from 5,00% to 11,04% and showed statistical difference between the evaluated genotypes. The mean values for basic density ranged from 478 kg.m-3 to 588 kg.m-3 and presented statistical differences, being classified into three distinct groups, where the clones belonging to Group 1 presented values about 6% higher than in Group 2 and 15% when compared to Group 3. The mean values observed for the high calorific value ranged from 4.609,33 kcal.kg-1 to 4.743,67 kcal.kg-1 , where clones 1, 4 and 10 stood out, values higher than the others evaluated. The percentage of total lignin of wood showed clonal effect among the different materials evaluated, where Group 1 stands out, ranging from 27,81 to 29,76%, with higher values than the others evaluated. The extractive content varied between 3,72 and 7,76% and significant differences were observed with the formation of two distinct groups, where clones 5, 6, 9 and 10 stand out, represented by Group 1, with values about 32% higher than the other clones evaluated. The energy density of the wood did not present statistical differences, however, genotype 10, E. urophylla x E. camaldulensis, presented considerably higher value than the others evaluated, a fact occurred due to the strong influence of other properties evaluated, such as basic density and superior calorific value. Through the use of cluster grouping, it was possible to identify two groups with similarity in relation to the evaluated properties, being clones 1, 4 and 10, represented by Group 1, which presented values, higher values for basic density, higher calorific value, total lignin content and extractive contents, which ensured superiority for energy use. It was concluded that the different genotypes evaluated presented satisfactory properties for use as an energy source, where the selection of superior materials can guarantee reduction of wood costs for drying grains by up to 20%.