Browsing by Author "Marreiros, A."
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- Correction of the misclassification of species in the Portuguese collection of Cucurbita pepo L. using DNA markersPublication . Rodrigues, R.; Veiga, I.; Marreiros, A.; Rocha, F.; Leitão, J. M.In this study, the genetic variability among 130 accessions of the Portuguese germplasm collection of Cucurbita pepo L. maintained at the Banco Portugues de Germoplasma Vegetal was assessed using AFLP (amplified fragment length polymorphism) and RAPD (random amplified polymorphic DNA) techniques for the identification of a genetically diverse core group of accessions for field phenotypic analysis. The surprisingly completely different molecular patterns exhibited by multiple accessions was later confirmed in the distribution of the putative C. pepo plants into two clusters drastically separated at a very low level of genetic similarity (DICE coefficient = 0.37). Additional analyses with RAPD and ISSR (inter single sequence repeat) markers and the introduction of standard genotypes of C. maxima L. and C. moschata L. into the analyses allowed the identification of multiple accessions of the last species wrongly included in the C. pepo collection. This study is a good example of the usefulness of DNA markers in the establishment and management of plant germplasm collections.
- Genetic diversity assessment of the almond (Prunus dulcis (Mill.) DA Webb) traditional germplasm of Algarve, Portugal, using molecular markersPublication . Cabrita, L.; Apostolova, E.; Neves, Alcinda; Marreiros, A.; Leitão, JoséIn this study, 123 almond (Prunus dulcis (Mill.) D. A. Webb) trees identified among traditional orchards in the Algarve region and 53 trees of the local field collection managed by the regional office of the Portuguese Ministry of Agriculture (DRAALG) were assessed using isozyme, inter- single sequence repeat and simple sequence repeat or microsatellite techniques for the evaluation of genetic diversity and genetic relatedness and identification of new accessions for the field collection. The isozyme analysis allowed the distribution of the 176 plants into 13 different classes of enzyme similarity, while the use of DNA markers increased the distribution of the analysed trees among 140 discriminating DNA patterns. Multiple cases of homonymy and synonymy were identified in the local germplasm. Some traditional varieties, such as Lourencinha, appeared to be relatively homogeneous, while other local denominations, e.g. Galamba, included diverse genotypes. Of the 13 commercial varieties analysed in this study, 11 assembled in one major cluster clearly differentiated from the majority of the local genotypes. These results reinforced the perception that the Algarve traditional germplasm constitutes an important repository of genetic diversity, eventually carrying alleles of high agricultural interest such as the recently identified Phomopsis resistance in the traditional variety Barrinho Grado.
- P-248 Futility and utility of two-stage hepatectomyPublication . Cunha, M.; Barros, I.; Marreiros, A.; Martins, A.; Pinto Marques, H.Meeting abstract in the European-Society-for-Medical-Oncology (ESMO) 21st World Congress on Gastrointestinal Cancer.
- Portuguese Cucurbita spp. and Citrullus lanatus: Conservation, Evaluation and BreedingPublication . Rocha, F. A.; Barata, A. M.; Quedas, F.; Lopes, F.; Marreiros, A.; Leitão, JoséCucurbitaceae is one of the most important families of vascular plants. This family includes 118 genera and 825 species. The five major cucurbit crops are Citrullus lanatus Thumb Mansf. (watermelon), Cucurbita maxima Duchesne (pumpkin), Cucurbita pepo L. (squash), Cucumis sativus L. (cucumber) and Cucumis melo L. (melon). Citrullus lanatus and Cucurbita spp. are very important in the Portuguese agro-ecosystems, associated with maize, beans and cabbage. Due to the importance of Citrullus and Cucurbita spp., the Portuguese National Genebank (BPGV) has done systematic collecting missions in Portugal (Mainland and Madeira Island). Since 2001, BPGV in partnership with other National Institutions, Escola Superior Agraria de Santarem, Direccao Regional de Agricultura e Pescas do Algarve and Universidade do Algarve, has been carrying out activities related to preservation, characterization, evaluation and pre-breeding. In Portugal, in BPGV, the Curcubitaceae collection preserved in ex situ conditions (medium and long term) totals 573 accessions. The collection of Citrullus lanatus and Cucurbita spp. has a total of 355 accessions, representing 62% of the whole collection: (37 of Citrullus lanatus, 19 of Cucurbita ficifolia, 74 of Cucurbita maxima and 224 of Cucurbita pepo). Based upon the diagnosis of the preserved collection, further germplasm collecting missions were recommended in Algarve Region. AFLP and RAPDs markers were used to check the assignment of accessions to Cucurbita species: C. pepo, C. maxima and C. moshata. The morphological characterization followed the Curcubita spp. and Citrullus descriptors, elaborated by Bioversity International, integrated in the European Cooperative Program for Genetic Resources, Cucurbits Working Group. Characterization data are reported herein. Departing from the most homogeneous accessions of Citrullus lanatus, Cucurbita maxima and C. moschata, three cultivars, one of each species, have already been selected and registered in the National Catalogue of Varieties.
- Predictors of in-hospital outcome in takotsubo cardiomyopathy, a multicenter studyPublication . Calvo, A. L. Ana; Azevedo, O.; Santos, R. P.; Almeida, A. R.; Craveiro, N.; Picarra, B.; Lima, R.; Reis, L.; Marmelo, B.; Marreiros, A.; Marques, Nuno; Amado, JoséTakotsubo cardiomyopathy (TC) is characterized by a transient left ventricular (LV) dysfunction in the absence of significant coronary artery disease. The predictors of prognosis of TC are not yet fully established