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- 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.
- Morphological characterization of wheat genetic resources from the Island of Madeira, PortugalPublication . Santos, Teresa M. M.; Ganança, Filipe; Slaski, Jan J.; Carvalho, Miguel Aˆ . A. Pinheiro deThis paper presents the first comprehensive morphological characterization and identification of the wheat populations collected on the Archipelago of Madeira and preserved at the ISOPlexis Germplasm Bank, the University of Madeira, Funchal. Fifty-two wheat populations representing Madeira’s Triticum diversity and a wide range of ecological conditions were evaluated based on the biometrical and cytometrical traits. Forty-six traits related to plant morphology, cytological and grain characteristics were included in a multivariate analysis. Taxonomic identification of the collected materials revealed the presence of 3 species, 2 subspecies and 16 botanical varieties among the Madeiran wheat germplasm. The obtained results were confirmed by the multivariate analysis since all accessions were grouped in clusters corresponding also to different taxonomic levels. The detailed description of the Madeiran wheat landraces may contribute also to the protection of the existing Triticum diversity as well as support efforts of conservation of landraces, proper germplasm preservation and utilization.
- Flavonoids in phylloclades discriminate endemic Semele androgyna chemotypes from MadeiraPublication . Ganança, F. T.; Charpentier, J. P.; Carvalho, M. Â. A. Pinheiro de; Thangadurai, D.; Joseph, C.; Franco, E.; Sousa, N.; Wilcock, C.C.; Jay-Allemand, C.; Santos, T. M. M. dosThirty-five randomly-collected Semele androgyna Kunth samples were screened by RP-HPLC for their phenolic composition. Fraction analysis allowed the detection of 17 different compounds. According to their retention times and UV spectra obtained by diode array analysis, these phenolics represent three classes: phenolic acids, flavones and flavonols. Co-chromatography with specific standards enabled identification of quercetin, rutin and quercitrin in Semele tissues for the first time. Polymorphism based on phenolic composition was evaluated using multivariate analysis and showed four distinct S. androgyna clusters. This polymorphism was not associated with morphological diversity or different in ambient light intensities. Biochemical differentiation is thus present in this species. The application of multivariate analysis techniques to RP-HPLC data has allowed the classification of samples into two groups, previously proposed on the basis of morphological and cytotaxonomical information. Therefore, the use of phenolics as chemotaxonomic markers in Semele is highly recommended because of its diagnostic value, even at a subspecies level. Discriminant canonical analysis and Mahalanobis distances confirmed these clusters as recognisable chemosystematic units. However, these units do not support the separation of S. pterygophora.
- Evaluation of wheat germplasm from the Madeira and Canary archipelagos using a single molecular marker. A rapid screening method for identification of durum wheat accessionsPublication . Andrade, V.; Santos, T.; Afonso Morales, D.; Costa, G.; Carvalho, M. Pinheiro deThis work aims to present a rapid and precise screening method of wheat germplasm and identification of durum wheat accessions in germplasm collections. Fifty-two wheat accessions maintained in the ISOPlexis germplasm bank at the Madeira University, Portugal, and 72 accessions from the Centre for Conservation of Crop Biodiversity of Tenerife (CCBAT), Spain, have been screened for their specific ploidy status using the molecular marker Dgas44. We have demonstrated that the Dgas44 sequence is effective in the screening of Madeiran and Canarian wheat accessions. This screening method permitted the detection of 10 and 11 durum accessions among Madeiran and Canarian wheats, accounting for 19.2 and 15.3% of screened collections, respectively. The obtained results have shown a 100% of cases correspondence with the previously performed morphological identification of the Madeiran wheats. It also permitted rectification and clarification of previous classification of some accessions based only on the morphological traits. The PCR based assay was directly applicable to the screening of seeds and was suitable for detecting seed mixtures in accessions. This rapid method has been proven to be a useful tool in gene bank accessions management including verification of their ploidy status and detection of seed lots adulteration.
- Soil conditions and evolution of aluminium resistance among cultivated and wild plant species on the Island of MadeiraPublication . Ganança, J. F. T.; Abreu, I.; Sousa, N. F.; Paz, R. F.; Caldeira, P.; Santos, T. M. M. dos; Costa, G.; Slaski, J. J.; Carvalho, M. Â. A. Pinheiro deSoil samples collected from different soil formations throughout the Island of Madeira were analysed for pH, aluminium (Al) and organic matter content. On average, the Madeira soils appeared to be acid with a mean pH of 5.01, containing 0.79 cmol/kg of ionic Al and 3.02% organic matter, which may create favourable conditions for the development of Al resistance among plant species inhabiting the island. Six plant species were evaluated for their resistance to Al using the erichrome cyanine R tests: three agricultural species including wheat (Triticum aestivum L. and Triticum turgidum L.) and corn (Zea mays L.) and three wild species from the genus Sinapidendron. Profound differences in adaptation to local edaphic parameters (Al content, acidity, organic matter, altitude) between cultivated and wild species were observed. Comparison of the distribution patterns of the cultivated and wild species on the island may indicate that the anthropogenic activities played a pivotal role in the development of enhanced Al resistance among the cultivated species, while edaphic conditions seem to be a secondary factor.
- Factors contributing to the development of aluminum resistance in the Madeiran maize germplasmPublication . Carvalho, Miguel Â. A. Pinheiro de; Slaski, Jan J.; Abreu, Ivo; Ganança, Filipe T.; Santos, Teresa M. M. dos; Freitas, Lurdes; Vieira, Maria R. Clemente; Nunes, Antonieta; Domingues, Ana; Taylor, Gregory J.
- Identification of aluminum resistant genotypes among Madeiran regional wheatsPublication . Carvalho, Miguel Â. A. Pinheiro de; Slaski, Jan J.; Santos, Teresa M. M. dos; Ganança, Filipe T.; Abreu, Ivo; Taylor, Gregory J.; Vieira, Maria R. Clemente; Popova, Tatyana N.; Franco, EmanuelForty-eight genotypes representing wheat diversity from the Island of Madeira were screened for resistance to aluminum (Al) in nutrient solution. Seeds of wheat used in the experiments were obtained from local farmers. The soil pH and content of ionic Al of plots cultivated with wheat were analyzed. The pH of topsoils varied between 3.83 and 6.59. The amount of ionic Al in soil samples varied between 0.38 and 1.36 cmol Al3 + per kg of soil and was positively correlated with the altitude of a plot. Eriochrome cyanine staining was used to evaluate the effect of Al ions on the root elongation. Seventy-two hour exposure of 3-day-old seedlings to 100 and 200 mM Al in nutrient solution revealed a high number of Al resistant genotypes among wheat germplasm. After withdrawal of Al stress, survival and root regrowth was observed in 28 and 23 genotypes screened at 100 and 200 mM Al in nutrient solution, respectively. Enhanced resistance to Al among Madeiran genotypes was associated with the amount of ionic Al in the soils. Complexity and various patterns of responses of tested cultivars to Al stress may suggest that Madeiran germplasm could be a valuable source of genes controlling Al resistance for conventional breeding programs and for studies of molecular bases of mechanisms of Al resistance.
- Purification and some catalytic properties of glucose-6-phosphate dehydrogenase isoforms from barley leavesPublication . Semenihina, A.; Popova, T.; Schnarrenberger, C.; Carvalho, M. A .A. Pinheiro de
- Helminth parasites from the stomach of conger eel, Conger conger, from Madeira Island, Atlantic OceanPublication . Costa, Graça; Santos, Maria J.; Costa, Luísa; Biscoito, Manuel; Carvalho, Miguel Â. A. Pinheiro de; Moreira, Egberto MeloGeographic variations in the diversity and prevalence of helminth parasites of fish can provide important clues as to the relatedness of fish populations. In the present work, the stomachs of 64 conger eels, Conger conger, collected during 1999 and 2000, were examined for the presence of parasites. Four fish were infected with L3 stages of the nematode Anisakis simplex s.l. (Anisakidae), 1 with the nematode Cristitectus congeri (Cystidicolidae), 1 with the acanthocephalan Rhadi norhynchus pristis, 17 with postlarvae of Sphyriocephalus tergestinus (Eucestoda: Trypanorhyncha), and 55 with Lecithochirium spp. (Digenea: Hemiuridae). The hemiurids were the most abundant parasites, with a total of 385 individuals recovered. Strong aggregated distributions were found for both the digeneans, Lecithochirium musculus and Lecithochirium fusiforme, with variance-to-mean ratios (s 2 /x) and index of discrepancy (D) 13.98 and 0.672 (for L. musculus) and 8.08 and 0.90 for L. fusiforme, respectively. Intensity of L. musculus, L. fusiforme, and S. tergestinus showed significant relationships with depth of capture. Differences in number of species and prevalence were found between Madeira and the Atlantic coasts of the Iberian Peninsula.