9 documents found, page 1 of 1
Geodiversity assessment of the Xingu drainage basin
Silva, Juliana; Pereira, D. I.; Aguiar, Alexandre; Rodrigues, CleideGeodiversity is a recent concept that refers to the abiotic variety of nature. It is defined as the range of geological (rocks, minerals, fossils), geomorphological (landforms, processes) and soil features, including their assemblages, relationships, properties, interpretation and systems. In this work, a method of quantitative assessment of geodiversity was applied to the Xingu drainage basin (Amazoˆnia – Braz...
Does selecting for improved growth affect wood quality of Pinus pinaster in Por...
Gaspar, Maria João; Lousada, José Luís; Rodrigues, José Carlos; Aguiar, Alexandre; Almeida, Maria HelenaThe selection criteria for the first generations in the Portuguese Pinus pinaster improvement program have been the growth rate and form traits. In this work we study the consequences of this selection on wood quality traits. This study assesses genetic and phenotypic correlation between growth, wood density components, lignin content and mechanical traits (radial modulus of elasticity and radial modulus of rup...
Age trends in genetic parameters of wood density components in 46 half-sibling ...
Gaspar, Maria João; Louzada, José Luís; Silva, Maria Emilia; Aguiar, Alexandre; Almeida, Maria HelenaThis study contributes to the Pinus pinaster Ait. breeding programme, which is reaching the third generation by adding information on wood quality of 46 open-pollinated families from a progeny trial located in Leiria, Portugal, that originated from seed collected in a clonal seed orchard. A total of 552 seventeen-year-old trees were sampled at 2 m height. Trends were studied from the pith outward in variance co...
Genetic correlations between wood quality traits of Pinus pinaster Ait.
Gaspar, Maria João; Louzada, José Luís; Aguiar, Alexandre; Almeida, Maria Helena• It is essential to understand how characteristics are related to each other in breeding programmes to select wood properties, in order to avoid that, in selecting for one trait, we are negatively affecting another. Moreover, measuring wood properties is time consuming and expensive. • This study assesses genetic and phenotypic correlations between wood density components and spiral grain of 46 half-sib famili...
Variations in growth, survival and carbon isotope composition among Pinus pinas...
Correia, Isabel; Almeida, Maria Helena; Aguiar, Alexandre; Alía, Ricardo; David, Teresa Soares; Pereira, J.S.To evaluate differences in growth and adaptability of maritime pine (Pinus pinaster Ait.), we studied growth, polycyclism, needle tissue carbon isotope composition (δ13C) as an estimate of water-use efficiency (WUE) and survival of seven populations at 10 years of age growing in a performance trial at a provenance test site in Escaroupim, Portugal. Six populations were from relatively high rainfall sites in Por...
Resposta de descendências de pinheiro bravo (Pinus Pinaster Ait.) ao stress hid...
Cerasoli, Sofia; Correia, Isabel; Aguiar, Alexandre; Almeida, Maria Helena; Chaves, Maria Manuela; Pereira, João SantosOs défices hídricos são, com frequência os principais factores limitantes para o crescimento do pinheiro bravo (Pinus Pinaster Ait.). Na actual perspectiva de alterações climáticas, prevê-se que a ocorrência do défice hídrico venha a aumentar em frequência e intensidade. Surge portanto a exigência de estudar a resposta fisiológica de varias descendências de pinheiro bravo ao stress hídrico de modo a identificar...
Análise da variabilidade de proveniências de pinheiro bravo na Mata Nacional do...
Correia, Isabel; Rocha, Eugénia; Pessoa, João; Aguiar, Alexandre; Almeida, Maria HelenaA importância silvícola e económica do pinheiro bravo, que representa 30% da área ocupada por espécies florestais no nosso País (DGF- 3º IFN 2001), conduziu a várias acções com vista ao melhoramento para esta espécie, no âmbito das quais foi instalado em 1992 um ensaio de proveniências em 6 locais de características ecológicas distintas. A importância da caracterização de populações de pinheiro bravo foi sublin...
Genetic resources in maritime pine (Pinus pinaster Aiton):molecular and quantit...
González Martínez, Santiago; Mariette, Stéphanie; Ribeiro, M.M.A.; Burban, Christian; Raffin, Annie; Chambel, Regina; Ribeiro, Carla AlexandraPinus pinaster is a conifer native to western Europe and northern Africa. Following on-going breeding programmes, provenance and progeny trials were established in some of the countries of the species’ range (France, Portugal and Spain) and quantitative traits were measured: growth, stem form, survival and pest and disease resistance, amongst others. Populations from the wide range of P. pinaster were recently ...
Genetic control growth, wood density and stem characteristics of Pinus pinaster...
Almeida, Maria Helena; Aguiar, Alexandre; Borralho, NunoA Pinus pinaster Ait. progeny trial involving 46 open pollinated families was established at two locations in Portugal (Leiria and Escaroupim). Height, diameter, Pilodyn and stem characteristics (straightness, branch size and number of whorls) were assessed at age 5 and 12 and were used to estimate variance components, heritability, phenotypic and genetic correlations between traits. Estimates varied considerab...