Browsing by Author "Ramos, A."
Now showing 1 - 7 of 7
Results Per Page
Sort Options
- Avaliação da maturação em azeitona Cobrançosa e Galega vulgar com recurso a diferentes metodologias baseadas na cor dos frutosPublication . Peres, F.; Ramos, A.; Vitorino, C.; Gouveia, C.; Ferreira-Dias, Suzana; Louro Martins, LuisaThis work aims to study three methods to evaluate the olive ripening state based on the colour changes of ‘Cobrançosa’ and ‘Galega Vulgar’ fruits, in early ripening. The relation between colour change and fat content was also performed. The methods under study were: IM – ripening index (Jaén) (with 8 groups of colour); IMS – simplified ripening index with only 3 colour classes; CI – colour index, using the CIE L*a*b* colour system. The results showed that ripening indexes based on the colour of fruits are very useful to characterize the fat accumulation in the olives. The IMS method showed a high correlation with IM. Also it is a rapid method to be used by olive growers for harvest time assessment
- Avaliação do estado nutricional azotado de pés-mãe de Eucalyptus globulus Labill. ssp. globulus com recurso a um medidor portátil de clorofilaPublication . Vasconcelos, E.; Ribeiro, H.M.; Ramos, A.; Coutinho, J.With the aim of evaluating the use of the portable chlorophyll meter “MinoltaSPAD 502” readings (SPAD readings) as an indicator of the nitrogen status of Eucalyptus globulus Labill. ssp. globulus (E. globulus) mother plants, a nitrogen fertilization experiment with this species was performed. Mother plants of two clones (HD 161 and CN5) of E. globulus were grown in an open-air nursery, in 12 L pots. Plants received 5 different nutrient solutions containing 50, 100, 200, 400 e 800 mg N L-1. During 1999, mother plants were subjected to a formative pruning. During 2000 and 2001 the following parameters were evaluated: number of cuttings produced, rooting ability of the cuttings, nitrogen content of the youngest fully expanded leaf, and leaf SPAD readings. Results obtained showed a significant asymptotic relationship between nitrogen availability and SPAD readings and a linear, positive and significant relationship between SPAD readings (y) and nitrogen leaf contents (x, g kg –1): y=23,27+0,75x; r=0.94; n=150. Results also showed a good fitting of quadratic model to the relationship between SPAD readings and the mother plants production (cuttings production and rooting ability of the cuttings). The determination coefficients (78%) were similar to those obtained when the model was adjusted to the relationship between leaf nitrogen and mother plants production (80%). Results indicate that, in this experiment, SPAD readings can be used to evaluate nitrogen status of E. globulus mother plants with a diagnostic “quality” similar to leaf nitrogen contents
- A fertilização azotada de pés-mãe de Eucalyptus globulus Labill.: efeito no crescimentoPublication . Vasconcelos, E.; Ribeiro, H.M.; Ramos, A.; Coutinho, J.To asses the effect of N fertilization on the growth of E. globulus stock plants, a nitrogen fertilization experiment was performed. During 3 years, stock plants of 2 clones (HD161 and CN5) were fertilized with complete nutrient solutions containing 5 different levels of N (50, 100, 200, 400 and 800 mg N L-1). Total biomass, leafbiomass, leaf area and number of shoots produced during the 3 years period were measured. Increasing levels of applied nitrogen till 400 mg N L-1 led to a significant increase of both biomass and shoot production. However, these productions were not significantly affected when N fertilization increased from 400 to 800 mg N L-1. Increasing levels of applied nitrogen also led to an increase of: i) total leaf area ii) specific leaf area (29% increase) and iii) leaf area ratio (13% increase), showing that with a higher N availability stock plants tend to improve their photosynthetic apparatus. Results show that nitrogen is a fundamental nutrient for the growth of E globulus stock plants and, as a consequence, nitrogen fertilization must be optimized. The maximum growth of E. globulus mother plants was achieved with 400 mg N L-1.
- Influência da intensidade de desfolha no microclima dos cachos, na produção e qualidade do mosto da casta trincadeiraPublication . Sereno, P.; Ramos, A.; Lopes, C.M.i\presentam-se os resultados de um ensaio de desfolha instalado em 2005 na Região do Ribatejo onde se estudou os efeitos de três intensidades de desfolha (DO-testemunha não desfolhada; D1-desfolha de três rolhas basais do lado nascente da sebe; D2-desfolha de três folhas basais dos dois lados da sebe) na densidade da sebe, produção e qualidade. A desfolha reduziu significativamente o número de camadas de folhas na zona de frutificação provocando um aumento da percentagem de radiação fotossinteticamente activa interceptada ao nível dos cachos e alterações na temperatura dos bagos. A desfolha não provocou quaisquer efeitos significativos quer em termos de escaldão dos bagos quer no peso dos cachos e produção. A desfolha provocou um aumento significativo do ,alcool provável do mosto à vindima que foi 11Into maior quanto maior a intensidade da desfolha. A acidez total do mosto também foi influenciada significativamente pela desfolha, tendo a modalidade testemunha não desfolhada apresentado o valor mais elevado e a D2 o mais baixo, enquanto a DJ apresentou um valor intermédio. Os vinhos das modalidades desfolhadas obtiveram melhores classificações nas provas organolépticas ao nível da qualidade do aroma e da apreciação global
- Influência da monda de cachos no rendimento e qualidade da casta ‘Aragonez’Publication . Ramos, A.; Sereno, P.; Lopes, C.M.Apresentam-se os resultados de um ensaio de monda de cachos instalado em 2005 na região do Ribatejo onde foram estudados os efeitos de duas intensidades de monda de cachos efectuado ao pintor (M33 monda de 33% dos cachos e M66 -monda de 66% dos cachos) comparativamente a uma testemunha nao mondada (MO) sobre o rendimento e qualidade da casta Aragonez. A monda não induziu diferenças significativas no peso dos bagos mas provocou uma redução significativa do rendimento, proporcional à intensidade de monda. A monda não provocou diferenças significativas no peso de lenha de poda mas, comparativamente à testemunha não mondada, a modalidade M66 deu origem a mostos e vinhos com maior grau alcoólico, menor acidez e pH mais elevado. A modalidade M33 registou valores intermédios em todos os parâmetros
- Molecular analysis of medium-chain acyl-CoA dehydrogenase deficiency in PortugalPublication . Luz, A.; Violante, S.; Gaspar, A.; Lobo, Antunes M.; Rivera, I. A.; Silva, M. F. B.; Ramos, A.; Rocha, H.; Sousa, C.; Marcao, A.; Fonseca, H.; Ventura, F. V.; Leandro, P.; Vilarinho, L.; Tavares, de Almeida,
- O comportamento de pés-mãe de Eucalyptus globulus Labill. sujeitos a diferentes níveis de azoto e potássioPublication . Vasconcelos, Ernesto; Ribeiro, H.M.; Ramos, A.; Coutinho, J.In Portugal the traditional propagation of Eucalyptus globulus Labill (E. globulus) by seed is being replaced by vegetative propagation by stem cuttings. However, for E. globulus, there is no sufficient information related to the management of mother plant fertilization. So, it is important to study the relationship between the fertilization of the mother plant and the rooting ability of the cuttings. With the aim of evaluating the effect of nitrogen and potassium on E. globulus mother plants, a fertilization experiment was performed during 2 years. 2 clones of E. globulus (clone HD161 and clone CN5) were fertilized, periodically, with 6 different nutrient solutions corresponding to 3 levels of nitrogen (50, 100 and 200 mg N L-1) and 2 levels of potassium (50 and 100 mg K L-1). In 1998, stock plants were subjected to formative pruning. In 1999, biomass, number of cuttings produced by the mother plants and rooting ability of the cuttings were evaluated. With the two levels of potassium applied no significant effects were found. On the contrary, increasing levels of nitrogen applied to the mother plants led to: i) an increase of total biomass, ii) a higherproduction of stem cuttings, iii) an improvement of the rooting ability of the cuttings. Results showed that nitrogen fertilization and, as consequence, nitrogen reserves, constitute a limiting factor for rooting in E. globulus cuttings. Thus, research on the optimization of nitrogen fertilization of E. globulus mother plants should be performed.