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Estrutura genética em populações de bracatinga (Mimosa scabrella Benth. ) por marcador isoenzimático e caracteres quantitativos.; Genetic structure in bracatinga populations (Mimosa scabrella Benth.) for quantitative traids and isozyme markers.

Sobierajski, Graciela da Rocha
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/12/2004 PT
Relevância na Pesquisa
46.36%
A Mimosa scabrella Bentham bracatinga) é uma espécie arbórea nativa da Mata Atlântica, de ocorrência restrita aos Estados do sul e sudeste do Brasil (RS, SC, PR, SP). A espécie vem sendo cultivada no sul do país e em outros países como Costa Rica e Ruanda, para os mais variados fins. Contudo, embora a espécie tenha diversas utilidades, muito pouco tem sido feito em termos de melhoramento genético. Assim, em Maio de 2003, um teste de procedências e progênies de M. scabrella foi instalado na Estação Experimental de Itatinga (ESALQ/USP), utilizando oito procedências nativas e uma comercial, coletadas ao longo da distribuição geográfica da espécie. O delineamento usado foi o Blocos de Famílias Compactas, com nove procedências, 10 a 20 progênies por procedência, seis plantas por subparcela e cinco repetições. Seis meses após o plantio foi medido o caráter altura total e sobrevivência de plantas no ensaio. Concomitantemente, uma amostra de aproximadamente 50 plantas por procedência foi usada para a analise de eletroforese de isoenzimas, revelando-se sete locos polimórficos. Os resultados mostraram que a espécie tem sistema misto de reprodução com predomínio de cruzamentos (média de tm = 0,971). Na média das procedências foi detectada 7...

Genetic Variation in an International Provenance-Progeny Test of Pinus caribaea Mor. var. bahamensis Bar. et Gol., in São Paulo, Brazil

Sebbenn, A. M.; Arantes, F. C.; Boas, O. V.; Freitas, M. L. M.
Fonte: J D Sauerlanders Verlag Publicador: J D Sauerlanders Verlag
Tipo: Artigo de Revista Científica Formato: 181-187
ENG
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96.53%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); A combined provenance-progeny test of Pinus caribaea var. bahamensis was established in Paraguacu Paulista Experimental Station, São Paulo State, Brazil, in a "compact family" blocks design with 14 provenances, 2 to 10 families per provenance, 5 individuals per subplot, and 7 replications. Variation among and within island, provenances and families and genetic parameters for d.b.h., height, and real volume were investigated, about 15 years after planting. Analysis of variation for all studied traits revealed significant differences among islands, provenances within island and families within islands, suggesting the possibility of increasing the timber yield through selection of the more productive provenances and families within the best island. Genetic correlations on growth traits were high and statistically significant, indicating that substantial gains could be made through indirect selection for one trait based on direct selection for another. Norman Castle provenance from Abaco Island performed best for d.b.h. height and volume, while San Andros and Little Harbour Cay, both from Andros Island performed worst for d.b.h. and height, respectively, and South Riding from Grand Bahamas Island performed worst for volume. The best provenance growth compared to that P elliottii var. elliottii species at the same experimental site suggests that P. caribaea var. bahamensis has high silvicultural potential for the Paraguacu Paulista region.

Variação e parâmetros genéticos em teste de progênies de polinização livre de Peltophorum dubium (Sprengel) taubert em Luiz Antonio -SP

Do Nascimento Senna, Sirlene; Freitas, Miguel Luiz Menezes; Zanatto, Antonio Carlos Scatena; Morais, Euripedes; Zanata, Marcelo; De Moraes, Mário Luiz Teixeira; Sebbenn, Alexandre Magno
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 345-352
POR
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46.28%
Intensive deforestation and forest fragmentation of the Brazilian forest biomes has contributed to increase the number of trees species under the risk of extinction. Peltophorum dubium (Sprengel) Taubert is one of these species. Some of its populations are being conserved ex situ by the Instituto Florestal de São Paulo through provenance and progeny tests. The aim of this study was to investigate the genetic variation and to estimate genetic parameters at age 24 years in a progeny test of P. dubium established in Luiz Antônio, São Paulo State, Brazil. The trial was established in a random block design, with six replications, five plants per plot and 18 open-pollinated progenies. Measured were: diameter at breast height (DBH), height and stem form. The genetic parameters heritability, genetic variation and effective population size were estimated. Significant genetic differences were observed only for DBH. This trait also presented a high coefficient of genetic variation (CV g=4.8%) and heritability, especially among progeny means (h m 2=0.6607). This indicates that DBH is the most indicated trait for selection in the population. The effective population size conserved ex situ in the test was estimated to be 38.9. Concerning genetic conservation...

Variação, parâmetros genéticos e seleção entre e dentro de procedências e progênies de Handroanthus vellosoi (Toledo) Mattos

Batista, Camila Moreira
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 81 f. : il.
POR
Relevância na Pesquisa
26.28%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Pós-graduação em Agronomia - FEIS; A intensa fragmentação dos habitats de ocorrência de Handroanthus vellosoi (Toledo) Mattos já extinguiu grande parte das populações naturais da espécie. Essa exploração inadequada vem comprometendo sua capacidade de sobrevivência nesses ambientes naturais. Neste contexto, as finalidades deste trabalho são a conservação ex situ, avaliação da variabilidade e estimativa de parâmetros genéticos em teste de procedências e progênies de polinização aberta da espécie arbórea tropical Handroanthus vellosoi por caracteres quantitativos. Mais especificamente, pretende-se estudar a herança de caracteres quantitativos, a correção entre estes caracteres e selecionar árvores superiores de H. vellosoi em um teste de procedências e progênies para a produção de sementes com ampla variabilidade genética para fins de recuperação ambiental. O teste foi instalado na Estação Experimental de Luiz Antônio, do Instituto Florestal de São Paulo em 1986. O delineamento experimental adotado foi o de blocos de famílias compactas, com seis repetições, com subparcelas lineares de cinco plantas provenientes de duas procedências...

Variação, herdabilidade e ganhos genéticos em progênies de eucalyptus tereticornis aos 25 anos de idade em Batatais – SP

Macedo, Hugo Rodrigo
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 51 f.
POR
Relevância na Pesquisa
26.06%
Pós-graduação em Agronomia - FEIS; A madeira do Eucalyptus tereticornis é utilizada para serraria, estruturas, construções, postes, mourões e carvão. É uma das principais espécies para o reflorestamento em zonas tipicamente tropicais da África e os plantios no Brasil tem bom desenvolvimento. Em todos os estudos efetuados a espécie vem revelando boa resistência a pragas, doenças e deficiências hídricas, boa capacidade de regeneração por brotação das cepas e tolerância ao fogo rasteiro, podendo ser recomendado para plantio em todas as regiões brasileiras. O presente trabalho visa o estudo de parâmetros genéticos em progênies de Eucalyptus tereticornis, oriundas de polinização aberta de árvores matrizes selecionadas em três populações da Austrália. O delineamento experimental utilizado para o ensaio foi o de blocos de famílias compactas, com o efeito de procedência alocado nas parcelas e de progênies dentro de procedências nas sub-parcelas. As parcelas foram compostas por seis plantas e o espaçamento adotado foi o de 3 x 2 m. Aos 25 anos de idade foram medidos o diâmetro a altura do peito (DAP), a altura total, e a forma das árvores. Foi encontrada variação genética nas três populações estudadas e a possibilidade de se obter altos ganhos com a seleção entre e dentro de progênies. A procedência que apresentou o melhor desempenho às características edafoclimáticas de Batatais-SP...

Variação, herdabilidade e ganhos genéticos em progênies de Eucalyptus tereticornis aos 25 anos de idade em Batatais-SP

Macedo, Hugo Rodrigo; Menezes Freitas, Miguel Luiz; Teixeira de Moraes, Mario Luiz; Zanata, Marcelo; Sebben, Alexandre Magno
Fonte: Ipef-inst Pesquisas Estudos Florestais Publicador: Ipef-inst Pesquisas Estudos Florestais
Tipo: Artigo de Revista Científica Formato: 533-540
POR
Relevância na Pesquisa
26.26%
The wood of Eucalyptus tereticornis is intensively used for timber, structures, buildings, poles, posts and coal. The aim of this study was to estimate genetic parameters and genetic and phenotypic correlations in growth and stem form traits of 52 open-pollinated progenies of E. tereticornis sampled from three Australian populations (20 progenies from Helenvale, 19 from Ravenshoe and 13 from Mt. Garnet). The progenies were compared with three commercial control also from Australian. The experimental design used was the compact family block, with the effect of provenance allocated in the plots and progenies within provenances in the subplots. Ten repetitions of the 52 treatments, sub-plots with six plants and the spacing of 3 x 2 m was used. At 25 years of age it was measured the diameter at breast height (DBH), total height, true volume and the stem form. We found genetic variation amon and within the three provenances and the possibility of obtaining high gains from mass selection and individual among and within progenies. The provenance Helenvale showed the best development for DBH, height and volume. The traits DBH, height and volume showed high genetic correlations (> 0.9), indicating the possibility to use the indirect selection. The coefficient of heritability on a progeny mean for the traits DBH and height was median...

Genetic variation among and within provenances and progenies of Corymbia maculata (Hook.) K. D. Hill and L. A. S. Johnson, in Pederneiras, SP

Sato,Aida Sanae; Freitas,Miguel Luiz Menezes; Lima,Israel Luiz de; Zimback,Léo; Toniato,Maria Teresa Zugliani; Sebbenn,Alexandre Magno
Fonte: UFLA - Universidade Federal de Lavras Publicador: UFLA - Universidade Federal de Lavras
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2010 EN
Relevância na Pesquisa
36.32%
This study aimed to estimate genetic parameters and variation in a provenance-progeny test of C. maculata (ex Eucalyptus maculata Hook.), conducted at Pederneiras Experimental Station, in São Paulo Forest Institute. The test was based on 21 open-pollination progenies from provenance Woondum St. Forest and 17 from provenance Wondai St. Forest, both in Australia. A compact family block design was adopted consisting of ten blocks, six plants per straight-line plot and two outer border rows, with spacing 3 x 2 m. Traits assessed included diameter at breast height (DBH), height, volume, form and survival rate at age 4 and 21 years. Significant differences were detected only at age 4 between provenances for DBH and height and among progenies for DBH, height and volume. The coefficient of genetic variation was higher for all traits at age 21. The heritability coefficient at the progeny level (h m²) was also higher at age 21 and ranged from 0.21 for volume to 0.40 for height, indicating that genetic progress can be achieved through selection of the best progenies. Genetic correlations were high between traits within and between age categories, showing that potential genetic gains can be achieved through indirect, early selection. Results indicate that considerable gains can be made if high selection intensity is applied among and within progenies...

Higher Levels of Multiple Paternities Increase Seedling Survival in the Long-Lived Tree Eucalyptus gracilis

Breed, Martin F.; Christmas, Matthew J.; Lowe, Andrew J.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 28/02/2014 EN
Relevância na Pesquisa
16.24%
Studying associations between mating system parameters and fitness in natural populations of trees advances our understanding of how local environments affect seed quality, and thereby helps to predict when inbreeding or multiple paternities should impact on fitness. Indeed, for species that demonstrate inbreeding avoidance, multiple paternities (i.e. the number of male parents per half-sib family) should still vary and regulate fitness more than inbreeding – named here as the ‘constrained inbreeding hypothesis’. We test this hypothesis in Eucalyptus gracilis, a predominantly insect-pollinated tree. Fifty-eight open-pollinated progeny arrays were collected from trees in three populations. Progeny were planted in a reciprocal transplant trial. Fitness was measured by family establishment rates. We genotyped all trees and their progeny at eight microsatellite loci. Planting site had a strong effect on fitness, but seed provenance and seed provenance × planting site did not. Populations had comparable mating system parameters and were generally outcrossed, experienced low biparental inbreeding and high levels of multiple paternity. As predicted, seed families that had more multiple paternities also had higher fitness, and no fitness-inbreeding correlations were detected. Demonstrating that fitness was most affected by multiple paternities rather than inbreeding...

Genetic variation among and within provenances and progenies of Corymbia maculata (Hook.) K. D. Hill and L. A. S. Johnson, in Pederneiras, SP; Variação genética entre e dentro de procedências e progênies de Corymbia maculata (Hook.) K. D. Hill and L. A. S. Johnson, em Pederneiras, SP

Fonte: UFLA - Universidade Federal de Lavras Publicador: UFLA - Universidade Federal de Lavras
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
36.32%
This study aimed to estimate genetic parameters and variation in a provenance-progeny test of C. maculata (ex Eucalyptus maculata Hook.), conducted at Pederneiras Experimental Station, in São Paulo Forest Institute. The test was based on 21 open-pollination progenies from provenance Woondum St. Forest and 17 from provenance Wondai St. Forest, both in Australia. A compact family block design was adopted consisting of ten blocks, six plants per straight-line plot and two outer border rows, with spacing 3 x 2 m. Traits assessed included diameter at breast height (DBH), height, volume, form and survival rate at age 4 and 21 years. Significant differences were detected only at age 4 between provenances for DBH and height and among progenies for DBH, height and volume. The coefficient of genetic variation was higher for all traits at age 21. The heritability coefficient at the progeny level (h m²) was also higher at age 21 and ranged from 0.21 for volume to 0.40 for height, indicating that genetic progress can be achieved through selection of the best progenies. Genetic correlations were high between traits within and between age categories, showing that potential genetic gains can be achieved through indirect, early selection. Results indicate that considerable gains can be made if high selection intensity is applied among and within progenies...

Higher levels of multiple paternities increase seedling survival in the long-lived tree eucalyptus gracilis

Breed, M.; Christmas, M.; Lowe, A.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
Relevância na Pesquisa
16.24%
Studying associations between mating system parameters and fitness in natural populations of trees advances our understanding of how local environments affect seed quality, and thereby helps to predict when inbreeding or multiple paternities should impact on fitness. Indeed, for species that demonstrate inbreeding avoidance, multiple paternities (i.e. the number of male parents per half-sib family) should still vary and regulate fitness more than inbreeding – named here as the ‘constrained inbreeding hypothesis’. We test this hypothesis in Eucalyptus gracilis, a predominantly insect-pollinated tree. Fifty-eight open-pollinated progeny arrays were collected from trees in three populations. Progeny were planted in a reciprocal transplant trial. Fitness was measured by family establishment rates. We genotyped all trees and their progeny at eight microsatellite loci. Planting site had a strong effect on fitness, but seed provenance and seed provenance × planting site did not. Populations had comparable mating system parameters and were generally outcrossed, experienced low biparental inbreeding and high levels of multiple paternity. As predicted, seed families that had more multiple paternities also had higher fitness, and no fitness-inbreeding correlations were detected. Demonstrating that fitness was most affected by multiple paternities rather than inbreeding...