Seleção genética em candeia (eremanthus erythropappus (DC.) macLeish) para sistema silvicultural de árvores porta sementes

Abstract

With the aim to select "candeia" trees (Eremanthus erythropappus) for use in silvicutural system of seed-bearer tress, a genetic test was installed by which 40 progenities of open pollination from an altitudinal range from 1200 to 1600 m were evaluated. The test was installed in a randomized blocks design, with three repetitions and six plants per linear portion with 3 x 2 m spacing. The diameter and height of the plants were obtained at the ages of 10, 24 and 80 months. The genetic parameters and the genotypic values were estimated and the wood quality was evaluated. The survival rate of the individuals of the experiment presented values above 70%. The progenities presented homogeneous growth, being found statistical differences only at 80 months. The herdability values in the restrict sense were from mean to low. The selection of the best individuals was performed based on the diameter found at 80 months. The analyses of total extractives and basic density were made in 56 individuals that belonged to the best 10 families of the test. The basic density values found varied from 0,55 to 0,60 g/cm³. The total extractives content percentage varied between 3.98 and 5.27 %. No statistical differences were found between the variables analyzed in the wood of the 10 progenities collected. The variation between genetic values of the progenities was low, allowing inferring that the genotypes belong to the same genic pool. Therefore, considering that there was no significant difference between the properties of the evaluated wood of the selected individuals, the selection of seed-bearer trees may be preceded based on the diameter at 80 months old.