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Conventionally morphological descriptors are routinely used for establishing the identity of varieties. This kind of descriptors has some disadvantages, namely most of them are quantitative, controlled by several pairs of genes, and their expression is infl uenced by environmental factors. Molecular markers have a potential to facilitate this procedure, increase the reliability of decisions, and substantially save the time and space needed for experiments. In this study we intended to identify 20 cultivars of fi eld pea (Pisum sativum L.), registered in the Community Catalog of Varieties, by microsatellites molecular markers. After DNA extraction, seven different loci were analyzed. PCR amplifi cations were conducted and the resulting fragments were separated on a 3.5% MS-8 agarose gel in TBE buffer. The gels were analyzed for the presence/absence of bands and a table with binary code was made. For each locus PIC value was calculated. The data were processed with the statistical software NTSYS-pc, using the SIMQUAL module and Jaccard similarity coeffi cient, followed by UPGMA cluster analysis. With the analysis of six polymorphic loci was possible to distinguish almost all of cultivars. The most informative loci were AD61 and AB53. The UPGMA dendrogram showed two main groups. The results showed a high potential and resolving power of SSR markers in distinct assessment. SSR markers might also be useful in germplasm management and genetic diversity studies. In the present research work, we have successfully employed high resolution agarose gel electrophoresis for genotyping with microsatellite markers in pea.
Comunicação apresentada no Seminário "Cereais e Leguminosas: Novas Perspectivas para a Beira Interior", que se realizou em 29 de Junho, em Castelo Branco, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco.
The aim of this study was to compare two rooting environmental conditions for root development, in vitro and ex vitro, and their influence in anatomical differentiation.
Comunicação apresentada no Simpósio de Propagação Vegetativa de Plantas Lenhosas que decorreu em Castelo Branco, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco, de 18 a 20 de Outubro de 1996.
A realização desta Jornada Técnica sobre o Castanheiro, inseriu-se no âmbito da divulgação do Potojecto PAMAF 6127.
Great advances have been made but some cultured plantlets still having a poor performance during the ex vitro stages and more specifically during the acclimatization and the nursery establishment stages. The problem is highly complex and requires the fast adaptation of plants growing in artificial conditions when transferred to the natural conditions. Until now, there is no consensus on the better strategy to obtain a higher efficiency of the propagation protocols while optimising acclimatization success. In this study we present the results of growth analysis of in vitro-regenerated chestnut hybrid plantlets (Castanea sativa x C. crenata), during the acclimatization stage, using two CO2 concentrations (350 µLL-1 and 700 µLL-1) at 250 µmol m- 2 s-1 as irradiance level (PPFD). Elevated CO2 did not affect the survival rate and it was susceptible to increase progressive autotrophy, expressed by a significant increase in relative growth, shoot/root ratio and leaf area ratio (LAR). For both CO2 concentrations, the plants are successfully acclimatized and they are in good conditions to be transferred to a greenhouse to continue their development for the rest of the season, and in the next winter/spring they can go to the field. The plants under elevated CO2 showed a higher stomatal frequency but the new leaves developed at the end of acclimatization revealed a gradual normal stomatal morphology and they reduced the stomatal frequency. Their morphology showed an effective water loss control, which is one of the most important problems during this critical phase of the autotrophic competence acquiring process. The net photosynthesis rate (A) was similar in both treatments but the plants acclimatized at elevated CO2 showed an increase in maximum photosynthetic rate (Amax), and this can lead to a better physiological development. The different analysed leaf types showed a marked increment of the maximum photosynthetic rate as the new leaves developed during the acclimatization stage. Net photosynthesis rate and the maximum photosynthetic rate are light dependent, and are positively affected by the highest irradiance level. We think that the gains that we have achieved with the use of elevated CO2 can be more significant if a higher light intensity can be used instead because they have a better response capacity to an increment of the level of irradiance.
Com o objectivo de desenvolver metodologias de micropropagação de Lavandula luisieri, foram realizados um conjunto de ensaios tendo como material vegetal explantes provenientes de germinação de sementes in vitro. Os ensaios de multiplicação estabelecidos com explantes secundários provenientes das plantas in vitro da população stock mostraram que a 6- benzilaminopurina se mostrou mais eficaz, comparativamente com a cinetina, na promoção e desenvolvimento dos rebentos tendo na concentração de 0.44 µM sido obtidos uma média de 2.2 rebentos com taxa de multiplicação de 3 e comprimentos de 20.9 mm. Contudo a utilização de concentrações mais elevadas de 6-benzilaminopurina são susceptíveis de promoverem elevadas taxa de vitrificação (35%) com consequente perda das culturas. Durante esta fase de multiplicação registou-se a formação de raízes nos rebentos tendo as percentagens de enraizamento sido maiores nos meios com cinetina, 57.5% com 0.46 µM, e no controlo. A aclimatização destas plantas foi feita com 100% de sobrevivência o que indicia o bom estado fisiológico das plantas regeneradas in vitro.
Abstract: Conventionally morphological descriptors are routinely used for establishing the identity of varieties. This kind of descriptors has some disadvantages, namely most of them are quantitative, controlled by several pairs of genes, and their expression is influenced by environmental factors. Molecular markers have a potential to facilitate this procedure, increase the reliability of decisions, and substantially save the time and space needed for experiments. In this study we intended to identify 20 cultivars of proteaginous pea (Pisum sativum L.), registered in the Community Catalog of Varieties, by microsatellites molecular markers. After DNA extraction, seven different loci were analyzed. PCR amplifications were conducted and the resulting fragments were separated on an 3,5% MS-8 agarose gel in TBE buffer, at 90V/h. The gels were analyzed for the presence/ absence of bands and a table with binary code was made. The data were processed with the statistical software NTSYS-pc, using the SIMQUAL module and Jaccard similarity coefficient, followed by UPGMA cluster analysis. With the analysis of six polymorphic loci was possible to distinguish almost all of cultivars. The most informative loci were AD61 and AB53. The cluster analysis of SSR markers separated the pea genotypes into two distinct clusters. The first cluster included the five cultivars: Isard, Cartouche, Audit, Corrent and James. The second cluster included the remaining fifteen cultivars and was further divided in two subclusters. The first subcluster had the Portuguese genotype Grisel and second subcluster contained the remaining fourteen cultivars. In this subcluster Ideal and Alezan had 100 percent similarity. There was a low number of heterozygous loci which is consistent with the nature of self pollinated species. The results showed a high potential and resolving power of SSR markers in distinctness assessment. SSR markers might also be useful in Pisum sativum L. germplasm management and genetic diversity studies.
Comunicação oral apresentada no II International Symposium on Acclimatization and Establishment of Micropropagated Plants que decorreu em 2004 em Cancún, no México.
The use of medicinal plants for the extraction of active pharmacological agents and precursors for chemical-pharmaceutical chemosynthesis has recently increased. The aim of this work was to study the establishment and multiplication phases of the in vitro propagation of common myrtle (Myrtus communis L.). In the establishment phase, the most suitable disinfection method was found by using increasing concentrations of commercial bleach (10%, 15% and 20%). It was discovered that commercial bleach at 15% allowed better results in the shoots survival rate (87%). The concentrations used to establish the explants from adult plant material did not allow however that all of them survived. This was possibly due to the some release of phenolic substances, and, also, to a certain toxicity of the disinfectant used, especially at the highest concentration. During the multiplication phase it was intended to assess the influence of light, through coloured bottle caps, on the shoots growth rate parameters, but we observed that it had no influence on the average of the longest shoot, on the average of the smaller shoot, and also, on the parameters related to the multiplication rate, the number of shoots and the number of shoot segments.
O conhecimento dos recursos existentes numa determinada região permite definir objectivos e implementar estratégias com vista à melhoria da qualidade de vida das respectivas populações. A valorização desses recursos possibilitará a dinamização da economia e o desenvolvimento sustentável dos mesmos. Este é um tema que tem merecido, nos últimos anos, a atenção das comunidades locais e regionais de algumas regiões do país. Reveste-se pois de extrema importância a definição e a operacionalização de políticas de desenvolvimento rural que contribuam, de forma eficaz, para uma inversão da tendência de diminuição demográfica que se tem vindo a observar nessas regiões. Contudo, existe um conjunto de aspectos espaciais e sociais que caracterizam o meio rural e lhe conferem uma identidade própria, específica e diferenciada, distinta da realidade urbana. É urgente valorizar os recursos locais, promovendo o desenvolvimento e a comunidade rural (Thirion e Cavaco, 2003). Desde os tempos mais remotos que se tem assistido a uma forte relação do homem com as abelhas. A agricultura desempenhou, através dos tempos, uma importância crucial para o nosso país. Contudo, actualmente, é uma actividade em contínuo declínio, resultado em grande parte das políticas agrícolas implementadas e do êxodo das populações rurais para meios urbanos. Actualmente, ao contrário do que se assistiu noutros tempos, a terra e a agricultura assumem, muitas vezes, uma função de complementaridade de outras actividades numa perspectiva de pluriactividade. Esta situação, além de contribuir directa e/ou indirectamente para a economia familiar, reveste-se também de uma função de previdência, pois constitui um recurso “seguro” contra a aleatoriedade dos ciclos/vínculos profissionais, cada vez mais precários e incertos. A prática apícola constitui uma das múltiplas actividades que podem originar outras fontes de rendimento complementar ou alternativo. O Município de Vila Velha de Ródão, região sobre a qual o estudo incidiu, apresenta boas condições edafo-climáticas para a prática apícola, apresentando uma floração sucessiva e diversificada, promovendo uma riqueza da flora melífera na região. Por outro lado, a actividade apícola apresenta inúmeros benefícios indirectos associados à produção agrícola. Será impensável equacionar a competitividade da nossa agricultura sem a presença de uma actividade apícola que a suporte (GPP, 2007). Todavia, o maior valor que as abelhas acrescentam no ambiente consiste no inquestionável auxílio à polinização, na manutenção dos ecossistemas terrestres, no equilíbrio ecológico da flora e na preservação da biodiversidade (GPP, 2007; Murilhas, 2008). O ordenamento do espaço físico constitui um instrumento necessário para que várias entidades, particularmente as municipais, o utilizem correctamente contribuindo com orientações compatíveis e congruentes ao nível da gestão territorial, para um aproveitamento integrado e economicamente sustentável do espaço rural (Carvalho et al., 2006; GPP, 2007). No decurso deste trabalho foi efectuado um levantamento da flora apícola mais importante no concelho de Vila Velha de Ródão e elaboradas fichas técnicas para servir de ferramenta de apoio aos apicultores e à comunidade em geral. Procedeu-se, ainda, à identificação e referenciação geográfica dos apiários existentes no concelho de Vila Velha de Ródão, geograficamente inserido na zona controlada e sob gestão da Associação de Apicultores do Parque Natural do Tejo Internacional. Com este trabalho é promovida a possibilidade de cruzamento de informações e a melhoria na cartografia, utilizando os dados recolhidos através das análises de mel produzido e/ou de possíveis patologias que possam ocorrer nos apiários. Em síntese, pretende-se identificar as potencialidades deste território nacional ao nível da prática apícola, a fim de dinamizar o sector e fomentar um aproveitamento integrado do espaço rural.
Endogenous levels of IAA, IAAsp and IBA were quantified during the first 8 days of in vitro rooting of the chestnut hybrid, clone M3 by high performance liquid chromatography. Rooting was induced either by dipping the basal ends of the shoots into 1 gl-1 IBA solution for 1 minute or by subculturing the shoots on agar rooting medium with 3 mgl-1 IBA for 5 days. For root development the induced shoots were transferred to auxin-free agar medium. Auxins were measured in the apical and basal parts of the shoots by means of high performance liquid chromatography. Endogenous levels of IAA and IAAsp were higher in IBA-treated shoots than in control shoots. In extracts of the basal parts of the shoots, the concentration of free IAA showed a transient peak at day 2, in both root inductive methods, a subsequent gradual decrease for the remainder of the time course was observed. The concentration of IAAsp peaked at day 6 in extracts of the basal parts of shoots induced with 3 mgl-1 IBA for 5 days, whereas shoots induced by dipping showed an initial increase until day 2, and then remained stable. In extracts from basal shoot portions induced by dipping and by IBA in the medium, IBA concentration showed a transient peak at 24 h and 48 h, respectively, remaining stable after day 4 for the dipping method, whilst showing a significant drop between day 4 and 6 for the other induction treatment. All quantified auxins remained at a relatively low level, virtually constant, in extracts from apical shoot portions, as well as in extracts from control of non-rooting shoots.