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- Recursos fitogenéticosPublication . Jesus, Isidoro; Carvalho, Miguel Ângelo Almeida Pinheiro deEste capítulo aborda os recursos fitogenéticos do cas- tanheiro no Arquipélago da Madeira e as metodologias utilizadas na sua avaliação. Os aspectos relacionados com as metodologias de caracterização destes recursos são analisados, nomeadamente os diferentes descritores morfológicos, bioquímicos e moleculares utilizados e as técnicas que dão suporte à avaliação dos mesmos. São apresentados os resultados preliminares da avaliação dos recursos do castanheiro, desenvolvidos com base num estudo de caracterização morfológica, sendo propostas 7 variedades regionais: curral, coração de boi, preta, mansinha, lisboa, santo antónio e formosa. Esta avaliação preliminar dos recursos do castanheiro deverá, no futuro, ser fundamentada com base em dados bioquímicos e moleculares. Por último, são abordadas as perspectivas de protecção desta cultura e da valorização da sua produção na Madeira.
- História, importância e distribuição do castanheiroPublication . Jesus, Isidoro; Carvalho, Miguel Ângelo Almeida Pinheiro deO presente capítulo aborda a história e a importância da cultura do castanheiro no Arquipélago da Madeira, assim como a sua distribuição actual na ilha da Madeira. Os aspectos relacionados com a distribuição geográfica da cultura e as condições edafo-ecológicas, em que se desenvolvem as principais cultivares desta espécie agro- -florestal, são caracterizados com o objectivo de explicar a diversidade de recursos genéticos existentes numa região de pequenas dimensões.
- Effects of Melatonin-aided therapy on the Glutathione antioxidant system activity and liver protectionPublication . Popov, Serguey S.; Shulgin, Konstantin K.; Popova, Tatyana N.; Pashkov, Aleksander N.; Agarkov, Aleksander A.; Carvalho, Miguel A. A. Pinheiro deAcute hepatitis results from oxidative stress triggered by hepatotoxic drugs causing liver injury and the activation of caspases cascade. The glutathione antioxidant system protects against reactive oxygen species and mitigates development of these processes. The effectiveness of silymarin, a polyphenolic flavonoid, essenthiale, composed of phosphatidyl choline, and melaxen, a melatonin-correcting drug, as hepatoprotectors has been investigated. The variation of 6-sulfatoxymelatonin (aMT6s), resulting from the biotransformation of melatonin, and GSH has been measured. The activities of caspase-1 and caspase-3, glutathione antioxidant system, and NADPH-generating enzymes were determined. The aMT6s decreases in patients with drug hepatitis and recovers with administration of mexalen. GSH increased in the presence of the studied hepatoprotectors. Pathologically activated caspase-1 and caspase-3 decreased their activities in the presence of hepatoprotectors with melaxen showing the highest effect. The positive effect of melatonin appears to be related to the suppression of decompensation of the glutathione antioxidant system functions, recovery of liver redox status, and the attenuation of inhibition of the NADPH supply.
- Variation of carbon and isotope natural abundances (δ15N and δ13C) of whole-plant sweet potato (Ipomoea batatas L.) subjected to prolonged water stressPublication . Gouveia, Carla S.S.; Ganança, José F.T.; Slaski, Jan; Lebot, Vincent; Carvalho, Miguel Â. A.Sweet potato (Ipomoea batatas L.) is an important crop in the world, cultivated in temperate climates under low inputs. Drought changes the plant biomass allocation, together with the carbon and nitrogen isotopic composition (δ13C and δ15N), whose changes are faintly known in sweet potato crops. Here, we show the biomass allocation of eight sweet potato accessions submitted to drought during 3 months, using the δ13C, δ15N, carbon isotope discrimination (Δ13C), total carbon (TC) and water use efficiency (WUE) traits. The tolerant accessions had improved WUE, with higher TPB and TC. Storage roots and shoots had a heavier δ13C content under drought stress, with greater 13C fixation in roots. The Δ13C did not show a significant association with WUE. The δ15N values indicated a generalised N reallocation between whole-plant organs under drought, as a physiological integrator of response to environmental stress. This information can aid the selection of traits to be used in sweet potato breeding programs, to adapt this crop to climate change.
- Phytogeographical origin of Madeiran common beans based on phaseolin patternsPublication . Silva, Emanuel Marques da; Correia, Anísia Soraia Abreu; Lopes, Nuno Alexandre Amaral; Nóbrega, Humberto Gil Moreira; Ganança, José Filipe Teixeira; Domingues, Ana Maria; Khadem, Manhaz; Slaski, Jan Jacek; Carvalho, Miguel Ângelo Almeida Pinheiro deThe objective of this work was to determine the geographic origin of the Madeiran common bean (Phaseolus vulgaris) gene pool. Phaseolin patterns of 50 accessions representing the diversity of common bean collected in Madeira, Portugal, and conserved in the ISOPlexis Germplasm Bank, were analysed using the Experion automated electrophoresis system, based on lab-on-a-chip technology. Five common bean standard varieties with typical phaseolin patterns were used to determine the phytogeographical origin of the Madeiran common bean accessions. Ninety two percent of the accessions exhibited a phaseolin pattern consistent with the one of common bean types belonging to the Andean gene pool, while the origin of the remaining 8% of the accessions was indistinguishable. The application of a similarity coefficient of 85%, based on Pearson correlations, increases the number of accessions with uncertain pattern. The analytical approach used permitted the determination of the origin of the common bean gene pool, which is Andean in 98% of the cases, and clustering of the observed variability among the Madeiran common beans.
- Review of sewage sludge as a soil amendment in relation to current international guidelines: a heavy metal perspectivePublication . Nunes, Nuno; Ragonezi, Carla; Gouveia, Carla S. S.; Carvalho, Miguel Â. A. Pinheiro deOverexploitation of resources makes the reutilization of waste a focal topic of modern society, and the question of the kind of wastes that can be used is continuously raised. Sewage sludge (SS) is derived from the wastewater treatment plants, considered important underused biomass, and can be used as a biofertilizer when properly stabilized due to the high content of inorganic matter, nitrate, and phosphorus. However, a wide range of pollutants can be present in these biosolids, limiting or prohibiting their use as biofertilizer, depending on the type and origin of industrial waste and household products. Long-term applications of these biosolids could substantially increase the concentration of contaminants, causing detrimental effects on the environment and induce hyper accumulation or phytotoxicity in the produced crops. In this work, some critical parameters for soils and SS agronomic use, such as organic matter, nitrogen, phosphorous, and potassium (NPK), and heavy metals concentration have been reviewed. Several cases of food crop production and the accumulation of heavy metals after SS application are also discussed. SS production, usage, and legis lation in EU are assessed to determine the possibility of sustainable management of this bioresource. Additionally, the World Health Organization (WHO) and Food and Agriculture Organization (FAO) guidelines are addressed. The opportunity to produce bioenergy crops, employing sewage sludge to enhance degraded land, is also considered, due to energy security. Although there are numerous advantages of sewage sludge, proper screening for heavy metals in all the variants (biosolids, soil, food products) is a must. SS application requires appropriate strict guidelines with appropriate regulatory oversight to control contamination of agricultural soils.
- Contributo para o conhecimento da agrodiversidade no concelho de Santa Cruz, MadeiraPublication . Carvalho, Miguel A. A. Pinheiro de; Ragonezi, Carla; Macedo, Fabrício Lopes de; Antunes, Gonçalo; Freitas, Gregório; Nóbrega, HumbertoO presente trabalho procura analisar as alterações sofridas pela agrodiversidade no território do Santa Cruz. Este concelho localizado na costa sul da Madeira tem 81,5 km2, quatro patamares bioclimáticos e numerosas unidades agroecológicas (UAE). A evolução da agrodiversidade iniciou-se, com o povoamento do Arquipélago, descoberto inabitado em 1418. A agrodiversidade biofísica, específica e intraespecífica aumentou e diversificou-se, devido à construção de agrossistemas, introdução de culturas, sucessão de ciclos agrícolas, adaptação às condições agroecológicas, aparecimento de pragas e doenças e pela ação do homem. Os registos históricos indicam a introdução de um elevado número de culturas, bem como a utilização de 72 espécies agrícolas, no concelho. E, indicam como fundamentais no povoamento e economia as culturas do trigo e as cerealíferas (cevada, centeio), cana-sacarina, vinha e sumagre. Várias outras culturas desempenharam um papel importante na economia do concelho, sendo cultivadas para fins alimentares, comerciais, industriais, culturais ou religiosos. A adaptação destas espécies aos agrossistemas e às condições agroecológicas deu origem a um número indeterminado de variedades locais. Apesar das limitações da documentação disponível, foram encontradas referências a variedades locais cuja cultura remonta há 140 a 500 anos, nomeadamente o Trigo da Serra, castas Malvasia e Tinta Antiga de Gaula, pêra Caniça, Banana da terra, feijão Corno de carneiro e Couve de João Ferino, que podem ser relacionadas com o historial do concelho. Porém, desde meados do século XX, a agrodiversidade sofreu uma drástica redução com a diminuição das áreas cultivadas, o abandono de várias espécies agrícolas e a extinção de variedades locais. A análise desta agrodiversidade foi realizada, a fim de apurar as alterações históricas e geográficas ocorridas na agrodiversidade em onze culturas representativas do concelho, visando a sustentabilidade agronómica.
- Abscisic acid phytohormone estimation in tubers and shoots of Ipomoea batatas subjected to long drought stress using competitive immunological assayPublication . Gouveia, Carla S. S.; Ganança, José F. T.; Slaski, Jan J.; Lebot, Vincent; Carvalho, Miguel Â. A. Pinheiro deSweet potato (Ipomoea batatas L.), typically cultivated in temperate climates under low inputs, is one of the most important crops worldwide. Abscisic acid (ABA) is an important plant stress-induced phytohormone. Hitherto, few works analyzed the ABA function in sweet potato tissue growth. Very scarce information is available concerning the ABA role in sweet potato response to water scarcity conditions. Here, we show the ABA content var iation in shoots and tubers of eight sweet potato accessions subjected to drought stress. ABA was also related to other resistance traits, such as chlo rophyll content index (CCI), carbon isotopic discrimination (Δ13C), oxalic acid (OA) and water use efficiency (WUE), to assess stress response mecha nisms to water deficit between their organs. The most resilient drought stressed sweet potato plants accumulated ABA-shoot, and significantly decreased the ABA-tuber content. ABA signaling was related to Δ13C and CCI decrease and WUE increment, as an attempt to cope with water stress by partially closing the stomata. The partial closure of stomata could be in part due to the presence of OA-shoots, known to affect the intensity of the ABA-shoot signal in stomatal closure. Higher CCI content and minimal Δ13C-shoot differences indicated good carboxylation fractionation, with higher Δ13C-tuber content as an indicator of efficient tuber 13C fixation and growth. Our work demonstrated that ABA could be used in conjunction with the other traits studied for the assessment of sweet potato whole-plant responses to environmental stresses, and thus aid the selection of the best drought tolerant genotypes for breeding programs.
- Evaluating the Madeiran wheat germplasm for aluminum resistance using aluminium-induced callose formation in root apices as a markerPublication . Santos, Teresa M. M. dos; laski, Jan J.; Carvalho, Miguel Â. A. Pinheiro de; Taylor, Gregory J.; Vieira, Maria R. ClementeAluminum (Al) resistance of 57 Madeiran wheat cultivars was evaluated using callose content in root tips and root elongation as markers. Al induced callose formation was a very sensitive indicator of Al damage detecting wide range of genotypic differences existing in the Madeiran wheat germplasm. A weak, yet pos i tive cor re la tion (R2=0.285, P<0.05) between callose content and root elongation was found.
- What can metazoan parasites reveal about the taxonomy of Scomber japonicus Houttuyn in the coast of South America and Madeira Islands?Publication . Oliva, M. E.; Valdivia, I. M.; Costa, G.; Freitas, N.; Carvalho, M. A. Pinheiro de; Sánchez, L.; Luque, J. L.The metazoan parasites of four populations of the chub mackerel Scomber japonicus were analysed from two localities in the Atlantic Ocean (Madeira Islands, Portugal, and Rio de Janeiro, Brazil) and two localities in the Pacific Ocean (Callao, Peru, and Antofagasta, Chile), collected during 2002 and 2003. A total of 373 fish specimens were studied and 34 metazoan parasite species were obtained. Parasites identified from the populations of chub mackerel studied could be separated into three categories: parasites with a wide distribution, present in the Pacific and Atlantic, parasites proper of the Pacific Ocean and parasites proper of the Atlantic Ocean. The analyses of some highly specific parasites of the genus Scomber (i.e. monogeneans of the genus Kuhnia and didymozoid digeneans) strongly suggest the need for a revision of the taxonomic status of chub mackerels from the Atlantic and Pacific coast of America. The results demonstrated the usefulness of parasites as adequate tools to clarify the taxonomic status of their hosts.