M Helena Almeida - Academia.edu (original) (raw)
Papers by M Helena Almeida
BMC …, 2011
Cork oak (Quercus suber L.) is one of the dominant broadleaved woody species in the western Medit... more Cork oak (Quercus suber L.) is one of the dominant broadleaved woody species in the western Mediterranean Basin, defining unique open woods. These woodlands have an outstanding economical and ecological value in this region, particularly in Portugal, where they sustain a strong ...
Wood and Fiber Science, 2007
The wood density of Eucalyptus globulus was measured as basic density in 7-year-old trees from 37... more The wood density of Eucalyptus globulus was measured as basic density in 7-year-old trees from 37 provenances grown in three sites, on cores taken at breast height. The wood density was highly significantly influenced by provenance and very significantly by site. The across-site range of variation of wood density in the different provenances was between 486 kg/m 3 and 430 kg/m 3 . The provenances of subspecies maidenii had a significantically higher density in relation to those from spp. globulus and bicostata (472 kg/m 3 vs. 448 kg/m 3 and 443 kg/m 3 ). No correlation between growth and density was found.
Forests
To anticipate European climate scenarios for the end of the century, we explored the climate grad... more To anticipate European climate scenarios for the end of the century, we explored the climate gradient within the REINFFORCE (RÉseau INFrastructure de recherche pour le suivi et l’adaptation des FORêts au Changement climatiquE) arboreta network, established in 38 sites between latitudes 37° and 57°, where 33 tree species are represented. We aim to determine which climatic variables best explain their survival and growth, and identify those species that are more tolerant of climate variation and those of which the growth and survival future climate might constrain. We used empirical models to determine the best climatic predictor variables that explain tree survival and growth. Precipitation-transfer distance was most important for the survival of broadleaved species, whereas growing-season-degree days best explained conifer-tree survival. Growth (annual height increment) was mainly explained by a derived annual dryness index (ADI) for both conifers and broadleaved trees. Species that...
BMC Genomics, 2014
Background: Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a... more Background: Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a material widely used to make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms of cork formation are still poorly understood, in great part due to the difficulty in studying a species with a long life-cycle and for which there is scarce molecular/genomic information. Cork oak forests are of great ecological importance and represent a major economic and social resource in Southern Europe and Northern Africa. However, global warming is threatening the cork oak forests by imposing thermal, hydric and many types of novel biotic stresses. Despite the economic and social value of the Q. suber species, few genomic resources have been developed, useful for biotechnological applications and improved forest management. Results: We generated in excess of 7 million sequence reads, by pyrosequencing 21 normalized cDNA libraries derived from multiple Q. suber tissues and organs, developmental stages and physiological conditions. We deployed a stringent sequence processing and assembly pipeline that resulted in the identification of~159,000 unigenes. These were annotated according to their similarity to known plant genes, to known Interpro domains, GO classes and E.C. numbers. The phylogenetic extent of this ESTs set was investigated, and we found that cork oak revealed a significant new gene space that is not covered by other model species or EST sequencing projects. The raw data, as well as the full annotated assembly, are now available to the community in a dedicated web portal at www.corkoakdb.org. Conclusions: This genomic resource represents the first trancriptome study in a cork producing species. It can be explored to develop new tools and approaches to understand stress responses and developmental processes in forest trees, as well as the molecular cascades underlying cork differentiation and disease response.
Soil bioengineering techniques are frequently used in restoration/mitigation projects due to thei... more Soil bioengineering techniques are frequently used in restoration/mitigation projects due to their ability to improve the potential for successful plant colonization and improve streambank stabilization. The application of these techniques in Mediterranean context reveals some implementation difficulties due to the torrential river regimes and subsequent high water table variation. Here we present two case studies that took place in Southern Portugal, using soil bioengineering techniques, with several years of follow up. The first one (2005) took place in Paul da Goucha, Alpiarça (Tagus river basin) and the second one (2011) in the Odelouca river (Algarve). Several different soil bioengineering techniques were used on these locations, including brush mattresses, geotextile rolls (planted and non-planted), live fascines, wattle fences, live stakes and others. Paul da Goucha is located in the Tagus River Basin, in the Alpiarça municipality. It is an area that has been heavily influenc...
Canadian Journal of Forest Research, 1999
This study contributes to the Pinus pinaster Ait. breeding programme, which is reaching the third... more This 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 components and narrow-sense heritability (h 2) of wood density components and ring-width characteristics as well as genetic correlations between cambial ages. Mean ring density (RD), minimum density (MND), maximum density (MXD), earlywood density (EWD), latewood density (LWD), earlywood width, latewood width, ring width, latewood percentage, and heterogeneity index were determined using X-ray densitometry procedures. RD had higher genetic control (h 2 = 0.63), and heritability values of earlywood components (h 2 MND = 0.54, h 2 EWD = 0.60) exceeded those of latewood components (h 2 MXD = 0.34, h 2 LWD = 0.26). Heritabilities increased with ring number from pith for almost all wood density components, and there were high age-age genetic correlations for wood density traits (rg > 0.98). Résumé : Cette étude s'inscrit dans le cadre d'un programme d'amélioration de Pinus pinaster Ait. qui débute son troisième cycle. Elle vise à documenter la qualité du bois chez 46 descendances issues de pollinisation libre découlant de semences récoltées dans un verger à graines clonal. Le test de descendances est situé à Leiria et un total de 552 arbres âgés de 17 ans ont été échantillonnés à une hauteur de 2 m. Les auteurs ont étudié les tendances des composantes de la variance et de l'héritabilité des composantes de la densité du bois et des caractéristiques des cernes annuels de la moelle à l'écorce de même que les corrélations génétiques entre les âges cambiaux. La densité moyenne des cernes (RD), la densité minimale (MND), la densité maximale (MXD), la densité du bois initial (EWD), la densité du bois final (LWD), la largeur du bois initial, la largeur du bois final, la largeur des cernes, le pourcentage de bois final et l'indice d'hétérogénéité ont été déterminés à l'aide de la densitométrie. Le contrôle génétique de RD (h 2 = 0,63) et les valeurs d'héritabilité des composantes du bois initial (h 2 MND = 0,54, h 2 EWD = 0,60) étaient plus élevés que ceux des composantes du bois final (h 2 MXD = 0,34, h 2 LWD = 0,26). Les héritabilités augmentaient de la moelle vers l'écorce pour la plupart des composantes de la densité du bois. Les corrélations génétiques entre différents cernes pour les caractères de densité du bois étaient élevées (r g > 0,98).
Atti del Secondo Congresso Internazionale di Selvicoltura = Proceedings of the Second International Congress of Silviculture, 2015
Forest Ecology and Management
Forest Ecology and Management
Cork oak (Quercus suber L.) has a high ecological and social value and supplies raw materials for... more Cork oak (Quercus suber L.) has a high ecological and social value and supplies raw materials for the cork industry, a relevant contributor to the economies of Mediterranean countries. Understanding the adaptation potential of cork oak populations to cope with different environmental conditions is a key issue of forest management, particularly for selecting the most adapted genetic material for (re)forestation and assuring the long-term sustainability of the cork industry. Intraspecific variation in fitness surrogate traits (survival, height and stem diameter) was investigated in thirty-five cork oak populations sampled from the entire range of the natural distribution of the species. The study was conducted in two provenance field trials, established in Portugal under different edaphoclimatic conditions. Each trial was surveyed at four tree ages (two ages, 11 and 14 years, were sampled simultaneously in both trials). The trial located at a lower altitude, which had higher mean winter and annual temperatures, exhibited higher growth and survival rates. In both trials, significant genetic variation among cork oak populations was observed for the analyzed traits and evaluated ages. Moroccan populations displayed a higher probability of survival and higher growth rates, while local populations exhibited an intermediate performance. Low to moderate correlations were found between the analyzed traits and the environmental variables of seed origin, suggesting that factors other than climate are likely to be relevant for cork oak adaptation. Moderate to high values of population mean-basis broad-sense heritability (H 2 ≥ 0.44) and high genetic correlations between traits (0.88-0.95) were found for growth traits. This information is crucial for the establishment of a breeding program for the species. With this study, we have improved the knowledge regarding how cork oak performs for fitness surrogate traits in different environments.
Silva Lusitana, Dec 1, 2004
Silva Lusitana 12(2): 151 - 182, 2004 © EFN, Lisboa. Portugal ... 1º Autor E-mail: isabel.correia... more Silva Lusitana 12(2): 151 - 182, 2004 © EFN, Lisboa. Portugal ... 1º Autor E-mail: isabel.correia@efn.com.pt ... Variabilidade do Crescimento e da Forma de Proveniências de Pinus pinaster Aiton aos 8 Anos, na Mata Nacional do Escaroupim
Silva Lusitana, Dec 1, 2004
Cuadernos De La Sociedad Espanola De Ciencias Forestales, 2008
Resumo. Tendo como base, a importância económica da Cryptomeria japonica na Região Autónoma dos A... more Resumo. Tendo como base, a importância económica da Cryptomeria japonica na Região Autónoma dos Açores, e face ao desconhecimento sobre a origem das populações, surgiu a necessidade de avaliar a variabilidade genética da população açoriana, para tal foi instalado um ensaio de proveniências. Paralelamente, a descendência de árvores seleccionadas em povoamentos locais, está a ser avaliada em ensaios de descendências para confirmação da sua superioridade e do controlo genético das características eleitas. Simultaneamente, através da utilização de marcadores moleculares pela técnica msp-PCR pretende-se antecipar informações relativamente à variabilidade genética das populações açorianas. A taxa de sobrevivência foi muita elevada em todos os ensaios, média acima dos 85%. Os acréscimos em altura total obtidos no 2º ano após a plantação, indicam diferenciação comportamental entre as plantas das origens açorianas e as da área de distribuição natural; as açorianas demonstram, em geral, melhores comportamentos. O ensaio de descendências ainda não permite a diferenciação de agrupamentos de famílias, embora se observem diferenças significativas entre estas. A análise da matriz dos coeficientes de similaridade de Dice indicou valores médios de similaridade relativamente elevados, na ordem dos 0,64, sendo o intervalo de variação mais estreito quando as populações açorianas foram comparadas entre si.
Silva Lusitana 12(2): 151 - 182, 2004 © EFN, Lisboa. Portugal ... 1º Autor E-mail: isabel.correia... more Silva Lusitana 12(2): 151 - 182, 2004 © EFN, Lisboa. Portugal ... 1º Autor E-mail: isabel.correia@efn.com.pt ... Variabilidade do Crescimento e da Forma de Proveniências de Pinus pinaster Aiton aos 8 Anos, na Mata Nacional do Escaroupim
To study adaptive variation and genotype x environment interactions (GE) of 30 populations from P... more To study adaptive variation and genotype x environment interactions (GE) of 30 populations from Portugal, Spain, France and Australia, we evaluated total height, diameter, stem form and survival in a multi-environment provenance trial in Portugal, 10 y after plantation, using the restricted maximum likelihood (REML) approach. • Significant differentiation was found among populations and also among seedlots from Portugal, populations from different altitude classes and from different provenance regions. Seed orchards showed significantly better growth and stem form. GE interaction was significant for all traits which indicates the existence of differences on phenotypic plasticity among populations, and displayed a pattern that could be related to general or specific adaptation of populations, and/or to humanmediated germplasm transfer. • Seed orchards, and the Monção and Leiria populations showed generally better growth and stem form, and some high altitude populations ranked higher in growth or survival (Bragança, S.Pedro do Sul, Manteigas-Pma30) at the high-altitude Montalegre site. There was a lack of genetic uniformity among populations of the same provenance region. • Tentative recommendations are made for afforestation, breeding and conservation.
This handbook provides the knowledge obtained during 3 years experiments with cork-oak acorn stor... more This handbook provides the knowledge obtained during 3 years experiments with cork-oak acorn storage (European Project FAIR5 CT97-3480), describing the practical aspects to ensure the success of the long-term storage of cork-oak acorns.
Caracterização do sistema radicular do sobreiro (Quercus suber L.) na fase inicial de desenvolvim... more Caracterização do sistema radicular do sobreiro (Quercus suber L.) na fase inicial de desenvolvimento: Efeito da proveniência e do tamanho da bolota
BMC …, 2011
Cork oak (Quercus suber L.) is one of the dominant broadleaved woody species in the western Medit... more Cork oak (Quercus suber L.) is one of the dominant broadleaved woody species in the western Mediterranean Basin, defining unique open woods. These woodlands have an outstanding economical and ecological value in this region, particularly in Portugal, where they sustain a strong ...
Wood and Fiber Science, 2007
The wood density of Eucalyptus globulus was measured as basic density in 7-year-old trees from 37... more The wood density of Eucalyptus globulus was measured as basic density in 7-year-old trees from 37 provenances grown in three sites, on cores taken at breast height. The wood density was highly significantly influenced by provenance and very significantly by site. The across-site range of variation of wood density in the different provenances was between 486 kg/m 3 and 430 kg/m 3 . The provenances of subspecies maidenii had a significantically higher density in relation to those from spp. globulus and bicostata (472 kg/m 3 vs. 448 kg/m 3 and 443 kg/m 3 ). No correlation between growth and density was found.
Forests
To anticipate European climate scenarios for the end of the century, we explored the climate grad... more To anticipate European climate scenarios for the end of the century, we explored the climate gradient within the REINFFORCE (RÉseau INFrastructure de recherche pour le suivi et l’adaptation des FORêts au Changement climatiquE) arboreta network, established in 38 sites between latitudes 37° and 57°, where 33 tree species are represented. We aim to determine which climatic variables best explain their survival and growth, and identify those species that are more tolerant of climate variation and those of which the growth and survival future climate might constrain. We used empirical models to determine the best climatic predictor variables that explain tree survival and growth. Precipitation-transfer distance was most important for the survival of broadleaved species, whereas growing-season-degree days best explained conifer-tree survival. Growth (annual height increment) was mainly explained by a derived annual dryness index (ADI) for both conifers and broadleaved trees. Species that...
BMC Genomics, 2014
Background: Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a... more Background: Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a material widely used to make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms of cork formation are still poorly understood, in great part due to the difficulty in studying a species with a long life-cycle and for which there is scarce molecular/genomic information. Cork oak forests are of great ecological importance and represent a major economic and social resource in Southern Europe and Northern Africa. However, global warming is threatening the cork oak forests by imposing thermal, hydric and many types of novel biotic stresses. Despite the economic and social value of the Q. suber species, few genomic resources have been developed, useful for biotechnological applications and improved forest management. Results: We generated in excess of 7 million sequence reads, by pyrosequencing 21 normalized cDNA libraries derived from multiple Q. suber tissues and organs, developmental stages and physiological conditions. We deployed a stringent sequence processing and assembly pipeline that resulted in the identification of~159,000 unigenes. These were annotated according to their similarity to known plant genes, to known Interpro domains, GO classes and E.C. numbers. The phylogenetic extent of this ESTs set was investigated, and we found that cork oak revealed a significant new gene space that is not covered by other model species or EST sequencing projects. The raw data, as well as the full annotated assembly, are now available to the community in a dedicated web portal at www.corkoakdb.org. Conclusions: This genomic resource represents the first trancriptome study in a cork producing species. It can be explored to develop new tools and approaches to understand stress responses and developmental processes in forest trees, as well as the molecular cascades underlying cork differentiation and disease response.
Soil bioengineering techniques are frequently used in restoration/mitigation projects due to thei... more Soil bioengineering techniques are frequently used in restoration/mitigation projects due to their ability to improve the potential for successful plant colonization and improve streambank stabilization. The application of these techniques in Mediterranean context reveals some implementation difficulties due to the torrential river regimes and subsequent high water table variation. Here we present two case studies that took place in Southern Portugal, using soil bioengineering techniques, with several years of follow up. The first one (2005) took place in Paul da Goucha, Alpiarça (Tagus river basin) and the second one (2011) in the Odelouca river (Algarve). Several different soil bioengineering techniques were used on these locations, including brush mattresses, geotextile rolls (planted and non-planted), live fascines, wattle fences, live stakes and others. Paul da Goucha is located in the Tagus River Basin, in the Alpiarça municipality. It is an area that has been heavily influenc...
Canadian Journal of Forest Research, 1999
This study contributes to the Pinus pinaster Ait. breeding programme, which is reaching the third... more This 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 components and narrow-sense heritability (h 2) of wood density components and ring-width characteristics as well as genetic correlations between cambial ages. Mean ring density (RD), minimum density (MND), maximum density (MXD), earlywood density (EWD), latewood density (LWD), earlywood width, latewood width, ring width, latewood percentage, and heterogeneity index were determined using X-ray densitometry procedures. RD had higher genetic control (h 2 = 0.63), and heritability values of earlywood components (h 2 MND = 0.54, h 2 EWD = 0.60) exceeded those of latewood components (h 2 MXD = 0.34, h 2 LWD = 0.26). Heritabilities increased with ring number from pith for almost all wood density components, and there were high age-age genetic correlations for wood density traits (rg > 0.98). Résumé : Cette étude s'inscrit dans le cadre d'un programme d'amélioration de Pinus pinaster Ait. qui débute son troisième cycle. Elle vise à documenter la qualité du bois chez 46 descendances issues de pollinisation libre découlant de semences récoltées dans un verger à graines clonal. Le test de descendances est situé à Leiria et un total de 552 arbres âgés de 17 ans ont été échantillonnés à une hauteur de 2 m. Les auteurs ont étudié les tendances des composantes de la variance et de l'héritabilité des composantes de la densité du bois et des caractéristiques des cernes annuels de la moelle à l'écorce de même que les corrélations génétiques entre les âges cambiaux. La densité moyenne des cernes (RD), la densité minimale (MND), la densité maximale (MXD), la densité du bois initial (EWD), la densité du bois final (LWD), la largeur du bois initial, la largeur du bois final, la largeur des cernes, le pourcentage de bois final et l'indice d'hétérogénéité ont été déterminés à l'aide de la densitométrie. Le contrôle génétique de RD (h 2 = 0,63) et les valeurs d'héritabilité des composantes du bois initial (h 2 MND = 0,54, h 2 EWD = 0,60) étaient plus élevés que ceux des composantes du bois final (h 2 MXD = 0,34, h 2 LWD = 0,26). Les héritabilités augmentaient de la moelle vers l'écorce pour la plupart des composantes de la densité du bois. Les corrélations génétiques entre différents cernes pour les caractères de densité du bois étaient élevées (r g > 0,98).
Atti del Secondo Congresso Internazionale di Selvicoltura = Proceedings of the Second International Congress of Silviculture, 2015
Forest Ecology and Management
Forest Ecology and Management
Cork oak (Quercus suber L.) has a high ecological and social value and supplies raw materials for... more Cork oak (Quercus suber L.) has a high ecological and social value and supplies raw materials for the cork industry, a relevant contributor to the economies of Mediterranean countries. Understanding the adaptation potential of cork oak populations to cope with different environmental conditions is a key issue of forest management, particularly for selecting the most adapted genetic material for (re)forestation and assuring the long-term sustainability of the cork industry. Intraspecific variation in fitness surrogate traits (survival, height and stem diameter) was investigated in thirty-five cork oak populations sampled from the entire range of the natural distribution of the species. The study was conducted in two provenance field trials, established in Portugal under different edaphoclimatic conditions. Each trial was surveyed at four tree ages (two ages, 11 and 14 years, were sampled simultaneously in both trials). The trial located at a lower altitude, which had higher mean winter and annual temperatures, exhibited higher growth and survival rates. In both trials, significant genetic variation among cork oak populations was observed for the analyzed traits and evaluated ages. Moroccan populations displayed a higher probability of survival and higher growth rates, while local populations exhibited an intermediate performance. Low to moderate correlations were found between the analyzed traits and the environmental variables of seed origin, suggesting that factors other than climate are likely to be relevant for cork oak adaptation. Moderate to high values of population mean-basis broad-sense heritability (H 2 ≥ 0.44) and high genetic correlations between traits (0.88-0.95) were found for growth traits. This information is crucial for the establishment of a breeding program for the species. With this study, we have improved the knowledge regarding how cork oak performs for fitness surrogate traits in different environments.
Silva Lusitana, Dec 1, 2004
Silva Lusitana 12(2): 151 - 182, 2004 © EFN, Lisboa. Portugal ... 1º Autor E-mail: isabel.correia... more Silva Lusitana 12(2): 151 - 182, 2004 © EFN, Lisboa. Portugal ... 1º Autor E-mail: isabel.correia@efn.com.pt ... Variabilidade do Crescimento e da Forma de Proveniências de Pinus pinaster Aiton aos 8 Anos, na Mata Nacional do Escaroupim
Silva Lusitana, Dec 1, 2004
Cuadernos De La Sociedad Espanola De Ciencias Forestales, 2008
Resumo. Tendo como base, a importância económica da Cryptomeria japonica na Região Autónoma dos A... more Resumo. Tendo como base, a importância económica da Cryptomeria japonica na Região Autónoma dos Açores, e face ao desconhecimento sobre a origem das populações, surgiu a necessidade de avaliar a variabilidade genética da população açoriana, para tal foi instalado um ensaio de proveniências. Paralelamente, a descendência de árvores seleccionadas em povoamentos locais, está a ser avaliada em ensaios de descendências para confirmação da sua superioridade e do controlo genético das características eleitas. Simultaneamente, através da utilização de marcadores moleculares pela técnica msp-PCR pretende-se antecipar informações relativamente à variabilidade genética das populações açorianas. A taxa de sobrevivência foi muita elevada em todos os ensaios, média acima dos 85%. Os acréscimos em altura total obtidos no 2º ano após a plantação, indicam diferenciação comportamental entre as plantas das origens açorianas e as da área de distribuição natural; as açorianas demonstram, em geral, melhores comportamentos. O ensaio de descendências ainda não permite a diferenciação de agrupamentos de famílias, embora se observem diferenças significativas entre estas. A análise da matriz dos coeficientes de similaridade de Dice indicou valores médios de similaridade relativamente elevados, na ordem dos 0,64, sendo o intervalo de variação mais estreito quando as populações açorianas foram comparadas entre si.
Silva Lusitana 12(2): 151 - 182, 2004 © EFN, Lisboa. Portugal ... 1º Autor E-mail: isabel.correia... more Silva Lusitana 12(2): 151 - 182, 2004 © EFN, Lisboa. Portugal ... 1º Autor E-mail: isabel.correia@efn.com.pt ... Variabilidade do Crescimento e da Forma de Proveniências de Pinus pinaster Aiton aos 8 Anos, na Mata Nacional do Escaroupim
To study adaptive variation and genotype x environment interactions (GE) of 30 populations from P... more To study adaptive variation and genotype x environment interactions (GE) of 30 populations from Portugal, Spain, France and Australia, we evaluated total height, diameter, stem form and survival in a multi-environment provenance trial in Portugal, 10 y after plantation, using the restricted maximum likelihood (REML) approach. • Significant differentiation was found among populations and also among seedlots from Portugal, populations from different altitude classes and from different provenance regions. Seed orchards showed significantly better growth and stem form. GE interaction was significant for all traits which indicates the existence of differences on phenotypic plasticity among populations, and displayed a pattern that could be related to general or specific adaptation of populations, and/or to humanmediated germplasm transfer. • Seed orchards, and the Monção and Leiria populations showed generally better growth and stem form, and some high altitude populations ranked higher in growth or survival (Bragança, S.Pedro do Sul, Manteigas-Pma30) at the high-altitude Montalegre site. There was a lack of genetic uniformity among populations of the same provenance region. • Tentative recommendations are made for afforestation, breeding and conservation.
This handbook provides the knowledge obtained during 3 years experiments with cork-oak acorn stor... more This handbook provides the knowledge obtained during 3 years experiments with cork-oak acorn storage (European Project FAIR5 CT97-3480), describing the practical aspects to ensure the success of the long-term storage of cork-oak acorns.
Caracterização do sistema radicular do sobreiro (Quercus suber L.) na fase inicial de desenvolvim... more Caracterização do sistema radicular do sobreiro (Quercus suber L.) na fase inicial de desenvolvimento: Efeito da proveniência e do tamanho da bolota