Avaliação da variabilidade genética em uma população de Oenocarpus bacaba Mart. em Juruti - Pa

Abstract

Genetic variability is extremely important for natural populations, as it enables the process of selecting characteristics of agronomic interest and choosing appropriate management. In this sense, the present study aimed to evaluate the genetic variability existing in a population of Oenocarpus bacaba Mart., through morphoagronomic characters, in the municipality of Juruti-PA, lower Amazon region. A population of O. bacaba Mart was evaluated. in the Três Bocas community, approximately 30 km from the urban area of the municipality. Initially, the area was delimited with the help of a GPS and, subsequently, the 7 fruiting matrices that were evaluated were identified, being: M1, M2, M3, M4, M5, M6 and M7. They were18 morphological characters were measured, evaluated partly at the collection site and partly in the Solo-Planta laboratory at Campus Juruti/UFOPA, 3 of which were vegetative characters, 7 were cluster characters and 8 were fruit characters. The data obtained was subjected to multivariate analysis to evaluate the 18 characters. To estimate the largest and smallest distance between the matrices, the Euclidean distance method was used to form pairs. Regarding the analysis of plant and bunch characters, data were obtained using the UPGMA method, generated based on Euclidean distances. For the analysis of fruit characters, data were analyzed based on Mahalanobis distances. In the analysis of vegetative characters, the number of bunches per plant and circumference at breast height presented the highest averages. Regarding cluster characters, the number of rachillae per cluster stood out among those analyzed. Regarding fruit characters, only two stood out, being the transversal diameter and thickness of the pulp. Related to the largest and smallest distances between the pairs formed regarding the plant and bunch, the highest value was 6.33, and the lowest value was 3.11. In the plant and bunch analysis presented in the dendrogram, individuals M2 and M3 showed proximity between them and M6 showed greater distance between all the matrices evaluated. In relation to the fruit, there were clusters forming five groups, with group I (M2 and M3) and group II (M5 and M7) being the closest and group V (M6) being the most genetically distant. The matrices of O. bacaba Mart. analyzed in the municipality of Juruti, in western Pará, showed significant genetic divergence for the morphoagronomic characters analyzed.