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- Adventitious rooting in microshoots of chestnut hybrid (Castanea sativa x C. crenata) in the presence of indole-3-butyric acid: The role of changes in endogenous indole-3-acetic acid, indole-3-acetylaspartic acid and indole-3- butyric acid levelsPublication . Gonçalves, José Carlos; Diogo, Maria da Graça; Coelho, Maria Teresa; Vidal, N.; Amâncio, SaraEndogenous 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.
- Sugar composition, phenolic content and antioxidant activity of P. tridentatum aqueous extracts: micropropagated shoots vs wild plantsPublication . Coelho, Maria Teresa; Diogo, Maria da Graça; Martins, Vítor R.; Coimbra, Manuel A.; Alves, Vítor; Gonçalves, José Carlos; Martins, Margarida MoldãoSugar composition, phenolic content and antioxidant activity of P. tridentatum aqueous extracts: micropropagated shoots vs wild plants.
- Natural extracts from Pterospartum tridentatum at different vegetative stages: extraction yiels, phenolic content and antioxidant activityPublication . Coelho, Maria Teresa; Pimenta, Catarina; Gonçalves, José Carlos; Alves, Vítor; Martins, Margarida MoldãoThe aerial parts of Pterospartum tridentatum, a wild growing species in Portugal used in traditional medicine and gastronomy, were harvested at different stages (vegetative phase, flowering phase and beginning of dormancy) in two locations in Portugal (Malcata and Gardunha mountains), and the respective aqueous extracts have been studied. The influence of the seasonal variation in the extraction yield, total phenolic content and antioxidant activity was evaluated. The extraction was carried out in boiling water in consecutive steps. After each step, the aqueous extract was separated and fresh water was added maintaining the same plant material. The procedure was repeated seven times, within an overall time period of 180 minutes. Higher extraction yields were achieved with plant stems collected at the vegetative phases, either from Malcata or Gardunha regions. The total phenolic content of the extracts from Malcata plants ranged from 273 mg to 400 mg gallic acid equivalent/g dry matter, which was quite similar to that determined for extracts from Gardunha (245 to 394 mg gallic acid equivalent/g dry matter). The antioxidant activity was determined by the radical scavenging activity method using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). The greatest radical scavenging activity was observed in the flowers extracts, even though all extracts produced presented a good antioxidant activity. Furthermore, the antioxidant activity was not affected by the exposure of the plant material at 100ºC for long periods of time (180 min). The results show that Pterospartum tridentatum has a great potential to be used as a new source of natural antioxidants for the food industry.
- Avaliação do estado vegetativo em montados de sobro na região de Castelo Branco.Publication . Cardoso, Teresa Ferrão; Gonçalves, José CarlosO diagnóstico das causas de mortalidade acentuada dos sobreiros nos concelhos de Castelo Branco, Vila Velha de Ródão e Idanha-a-Nova, veio contribuir para um conhecimento quantificado da situação destes ecossistemas. Foi assim possível avaliar a acção de vários factores relativos à situação fisiológica, ecológica, edafo-climática, sanitária, de exploração e de condução destes sistemas agro-florestais e também das interacções entre eles. Concluiu-se que a situação de declínio verificada é consequência da acção conjugada dos factores acima referidos, que actuam a médio/longo prazo e como tal difíceis de controlar. Consideramos também que o futuro destes ecossistemas, de grande importância económica e ecológica, depende eventualmente de um reordenamento do espaço por eles ocupado, o qual deverá ser definido por condicionantes de ordem não só florestal mas também de opções agrícolas e sócio-económicas que conduzam a um desenvolvimento sustentado das zonas de montado.
- Centro de Biotecnologia de Plantas da Beira Interior (CBPBI)Publication . Gonçalves, José CarlosO Centro de Biotecnologia de Plantas da Beira Interior (CBPBI) é uma infraestrutura do Sistema Científico e Tecnológico Nacional, criado na Escola Superior Agrária de Castelo Branco ao abrigo de um protocolo de colaboração técnica e científica entre o Instituto Politécnico de Castelo Branco, a Universidade da Beira Interior, o Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas da Universidade de Campinas, Brasil e o Biocant Park de Cantanhede.
- Efeitos da conservação in vitro a 4ºC na sobrevivência e proliferação da cerejeira (Prunus avium L.)Publication . Gonçalves, José Carlos; Coelho, Maria TeresaA utilização de técnicas in vitro para o armazenamento e conservação de germoplasma, apresenta-se hoje como uma alternativa de valor potencial aos tradicionais métodos de conservação. De facto, a possibilidade de manter partes vegetativas de plantas em condições limitadas de espaço e manutenção por longos períodos de tempo, tornam essas técnicas suficientemente atractivas para constituírem no futuro uma garantia da manutenção de recursos genéticos escassos e limitados. Neste estudo referem-se os resultados obtidos na conservação pelo frio de rebentos axilares de cerejeira com 1 ± 0.2 com de comprimento, obtidos a partir de culturas com 1 ano de idade e mantidos a 4ºC em meio de MS com diferentes concentrações de sacarose e de reguladores de crescimento, quer na sobrevivência, quer nas taxas de proliferação, durante três subcultivos sucessivos após o período de conservação de 3, 6, 9 e 12 meses. A presença de sacarose mostrou ser determinante para a sobrevivência dos explants, o mesmo já não acontecendo às diferentes combinações dos reguladores de crescimento utilizados, BAP e AIA. Decréscimos na sobrevivência começaram a registar-se a partir dos 9 meses de conservação, apesar dos explants sobreviventes continuarem a apresentar capacidade proliferativa. As taxas de multiplicação e alongamento dos rebentos foram em geral afectadas no primeiro subcultivo após a conservação, mas estes valores normalizaram ao longo do segundo e terceiro subcultivo.
- Cistus ladanifer (Cistaceae) : a natural resource in Mediterranean-type ecosystemsPublication . Frazão, David F.; Raimundo, Joana; Domingues, Joana Lopes; Quintela-Sabarís, Celestino; Gonçalves, José Carlos; Delgado, F.M.G.Cistus ladanifer has a well-defined taxonomic identity. 2,2,6-trimethylcyclohexanone may be an authenticity and taxonomic marker. Its traits and applications make it a possible economic resource fitted for Mediterranean areas. Cistus ladanifer is a dominant shrub species endemic to the western Mediterranean region. Due to its dominant nature and its potential ecological, aromatic or pharmacological applications, C. ladanifer has been the object of numerous studies. In this review current knowledge on different aspects of this species is summarized, from its taxonomy to its chemical characterisation or its competitive traits. There are no doubts about the taxonomic entity of C. ladanifer, although the recognition of infraspecific taxa deserves more attention. Given that the fragrant exudate of C. ladanifer holds a very specific composition, one species specific carotenoid, 2,2,6-trimethylcyclohexanone, derivative is proposed as an authenticity marker for uses of C. ladanifer in pharmacological or aromatic industries. Evidence is also gathered on the extreme adaptation of C. ladanifer to stressful conditions in the Mediterranean region, such as the ability to survive in low hydric and high solar exposition conditions, presistence in poor and contaminated soils, and growth inhibition of several other plants through the release of allelochemicals. Thus, the finding of potential applications for this plant may contribute to enhance the economic dimension of derelict lands, such as mine tailings or poor agricultural Mediterranean areas.
- Rockrose land management : contribution of periodic harvesting to increase value and to control Cistus ladanifer L. shrublandsPublication . Frazão, David F.; Gonçalves, José Carlos; Silva, Amélia M.; Delgado, F.M.G.: Cistus ladanifer L. (Cistaceae) occupies extensive areas as a dominant species (shrublands) or is associated to other major forest typologies in the Iberian Peninsula. Cistus ladanifer shrublands are mostly present in oligotrophic lands with little valorisation and management and as they develop over the years (up to 20-years-old) they promote the ignition and perpetuation of fire. To contribute to the proper management and valorisation of such systems, a 5-year-old dense shrubland was evaluated for its labdanum resin, seeds, and biomass productivity using different non-destructive harvest periodicities (annual and biennial) and seasons (early, mid-, and late summer), in a two-year case-study. Annual harvest modality maximized labdanum resin productivity (reaching 230 ± 50 kg·ha−1 ·2 years−1 at late summer) and photosynthetic biomass productivity. In contrast, a biennial harvest yielded significant amounts of more diversified products. It maximized seeds productivity (reaching 75 ± 41 kg·ha−1 ·2 years−1 independently of the summer season) and lignified biomass. However, it also reached a labdanum resin productivity of 134 ± 20 kg·ha−1 ·2 yearrs−1 at late summer and a photosynthetic biomass productivity around two times lower than the annual harvest. In this study, we propose two modalities of periodic harvest to be considered as proper long cycle management practices of rockrose lands. It intends to minimize fire risks, break the vegetation auto-succession mechanism, and increase profit from nonproductive lands based on three direct outputs with a myriad of applications and valorisation pathways.
- Comparative study between in vitro and in vivo developing root systems in micropropagated chestnutPublication . Gonçalves, José Carlos; Coelho, Maria Teresa; Diogo, Maria da GraçaThe 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.
- Centro de Biotecnologia de Plantas da Beira InteriorPublication . Gonçalves, José CarlosCentro de Biotecnologia de Plantas da Beira Interior.