Desbaste seletivo de um teste de procedências e progênies de Astronium fraxinifolium e Jacaranda cuspidifolia com base na variação genética de caracteres quantitativos

• Ano de defesa: 2016
• Autor(a) principal: Cornacini, Maiara Ribeiro [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Conservação genética; Espécies nativas; Manejo florestal; Gonçalo alves; Jacarandá caroba; Genetic conservation; Native species; Forest management
• Link de acesso: http://hdl.handle.net/11449/144415

The aim is to propose a management plan for progeny and provenance tests of Astronium fraxinifolium Schott and Jacaranda cuspidifolia Mart. It will be based on knowledge of genetic variability in an effort to promote the conservation of their genetic potential for commercial and environmental purposes. The test was originally installed in 1996 in Selvíria, Mato Grossa do Sul (MS) using an experimental design of randomized complete block design. We applied a total of 30 treatments (progenies) of provenance in Ilha Solteira, São Paulo (SP) and 30 treatments of provenance in Selvíria, MS with five repetitions for A. fraxinifolium and 30 treatments and 10 repetitions for J. cuspidifolia. The experimental plots were installed in a linear array, with 10 plants per plot, spaced 3 × 1.5m in alternate plantings. The silvicultural traits of both species were measured from 18 years after planting and sex determination of A. fraxinifolium individuals. The estimates of variance components and genetic parameters were obtained by employing the genetic statistical software SELEGEN-REML / BLUP. To investigate the genetic diversity the Mahalanobis distances and grouping of Tocher optimization model was used. It detected significant differences among provenances for DAP and ALT, between and within progenies for all growth traits, except FOR within progenies in A. fraxinifolium. The heritability coefficient average level progenies ranged from 0.59 to 0.89 and individual heritability from 0.14 to 0.35. The accuracy was high (> 0.65) and the coefficient of genetic variations were higher than 5.6. From total number of A. fraxinifolium individuals of just 11% and 16% are in flowering from Ilha Solteira, SP and Selvíra, MS provenances, respectively; with a predominance of individuals with male flowers. The Mahaloanobis distance was found at a maximum distance of 31.75 and a low of 0.23 between progenies. The A. fraxinifolium progenies of Ilha Solteira and Selvíria were grouped into eight and four groups. J. cuspidifolia progenies were grouped into six groups. The selection strategy within progenies, with selection of 50% of individuals based on DAP trait, revealed low gains in the selection. However, it is more suitable for this test because it does not alter the genetic structure of the population nor does it reduce the likelihood of crossings between relatives. Therefore, this proposal for selective thinning is most appropriate as the flowering percentage of individuals is low, making it impractical sex determination of total individuals. Consequently, the estimates of the parameters accurately suggest such an application is at a high level of selective high intensity.