Loading...
6 results
Search Results
Now showing 1 - 6 of 6
- Cereal landraces genetic resources in worldwide GeneBanks. A reviewPublication . Carvalho, Miguel A. A. Pinheiro de; Bebeli, Penelope J.; Bettencourt, Eliseu; Costa, Graça; Dias, Sonia; Santos, Teresa M. M. dos; Slaski, Jan J.Since the dawn of agriculture, cereal landraces have been the staples for food production worldwide, but their use dramatically declined in the 2nd half of the last century, replaced by modern cultivars. In most parts of the world, landraces are one of the most threatened components of agrobiodiversity, facing the risk of genetic erosion and extinction. Since landraces have a tremendous potential in the development of new cultivars adapted to changing environmental conditions, GeneBanks holding their genetic resources potentially play an important role in supporting sustainable agriculture. This work reviews the current knowledge on cereal landraces maintained in GeneBanks and highlights the strengths and weaknesses of existing information about their taxonomy, origin, structure, threats, sampling methodologies and conservation and GeneBanks’ documentation and management. An overview of major collections of cereal landraces is presented, using the information available in global metadatabase systems. This review on winter cereal landrace conservation focuses on: (1) traditional role of GeneBanks is evolving beyond their original purpose to conserve plant materials for breeding programmes. Today’s GeneBank users are interested in landraces’ history, agro-ecology and traditional knowledge associated with their use, in addition to germplasm traits. (2) GeneBanks therefore need to actively share their germplasm collections’ information using different channels, to promote unlimited and effective use of these materials for the further development of sustainable agriculture. (3) Access to information on the 7.4 million accessions conserved in GeneBanks worldwide, of which cereal accessions account for nearly 45 %, particularly information on cereal landraces (24 % of wheat, 23 % of barley, 14 % of oats and 29 % of rye accessions), is often not easily available to potential users, mainly due to the lack of consistent or compatible documentation systems, their structure and registration. (4) Enhancing the sustainable use of landraces maintained in germplasm collections through the effective application of recent advances in landrace knowledge (origin, structure and traits) and documentation using the internet tools and data providing networks, including the use of molecular and biotechnological tools for the material screening and detection of agronomic traits. (5) Cereal landraces cannot be exclusively conserved as seed samples maintained under ex situ conditions in GeneBanks. The enormous contribution of farmers in maintaining the crop and landraces diversity is recognised. Sharing of benefits and raising awareness of the value of cereal landraces are the most effective ways to promote their conservation and to ensure their continued availability and sustainable use. (6) Evaluation of costs and economic benefits attributed to sustainable use of cereal landraces conserved in the GeneBanks requires comprehensive studies conducted on a case-by-case basis, that take into consideration species/crop resources, conservation conditions and quality and GeneBank location and functions.
- Morphological evaluation of common bean diversity on the Island of MadeiraPublication . Freitas, Gregório; Ganança, José F.T.; Nóbrega, Humberto; Nunes, Élvio; Costa, Graça; Slaski, Jan J.; Carvalho, Miguel Â. A. Pinheiro deThe variability of fifty populations of common bean (Phaseolus vulgaris L.), representing a wide range of ecological conditions on the Island of Madeira, was evaluated based on morphological and reproductive traits. Individual data of 58 traits related to earliness, plant and tassel structure and the shape of the ear and grain were analysed using multivariate analysis. The populations belonging to two major common varieties were clustered into fifteen groups by their degree of dissimilarity, based on discriminant analysis. The dissimilarity of these groups was con- firmed by one way ANOVA. The racial rank of these groups was proposed and a brief description of the common bean landraces was presented. This work represents the first morphological characterization and analysis of diversity of bean germplasm from the Archipelago of Madeira, where the traditional agricultural practices are still keeping this Portuguese region free from improved bean varieties. The description of the Madeiran bean landraces allows the preservation of the existing bean biodiversity and could be used for their registration as conservation landraces, or for conservation and breeding purposes worldwide.
- 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.
- Distribution and abundance of Beta patula Aiton and other crop wild relatives of cultivated beets on MadeiraPublication . Carvalho, Miguel A.A. Pinheiro de; Nóbrega, Humberto; Frese, Lothar; Freitas, Gregório; Abreu, Uriel; Costa, Graça; Fontinha, SusanaIn the Archipelago of Madeira four crop wild relatives of beets are native: Beta patula, Beta vulgaris subsp. maritima, Patellifolia procumbens, and Patellifolia patellaris. All species are valuable genetic resources for the sugar beet breeding. Only in the very eastern part of the Madeira Island on the islet Ilhéu do Desembarcadouro and Ilhéu Chão the endemic species Beta patula can be found. On both islets the plant number of this very rare species, and of the two widely distributed species B. vulgaris subsp. maritima and P. procumbens was established and the habitat described. The results of the species census are presented. The establishment of a genetic reserve for Beta patula is suggested in this paper with the objective to protect this species more effectively.
- Oncophora melanocephala (Nematoda, Camallanidae) from the chub mackerel, Scomber japonicus (Teleostei, Scombridae), caught off Madeira Island (Portugal)Publication . Costa, Graça; Freitas, Nélio; Carvalho, Miguel Pinheiro de; Moreira, Egberto Melo; Rigby, MarkWhile investigating the nematode parasites of commercial fish caught off the coast of Madeira Island (Atlantic Ocean, Portugal), we collected five specimens of Oncophora melanocephala (Rudolphi, 1819) (Nematoda, Camallanidae) infecting the chub mackerel Scomber japonicus Houttuyn. This is the first record of O. melanocephala from chub mackerel and a new geographic record. Four additional larval specimens with developing buccal capsules were found in the chub mackerel examined.
- Helminth component community of the loggerhead sea Turtle,Caretta caretta from Madeira Archipelago, PortugalPublication . Valente, Ana Luisa; Delgado, Cláudia; Moreira, Cláudia; Ferreira, Sandra; Dellinger, Thomas; Carvalho, Miguel A. A. Pinheiro de; Costa, GraçaThe helminth fauna of pelagic-stage loggerhead sea turtles, Caretta caretta, is still poorly known. Here, we describe the helminth-component community of healthy, free-ranging juvenile loggerhead sea turtles captured in the waters around Madeira Island, Portugal. Fifty-seven were used in this study. The esophagus, stomach, intestine, liver, gallbladder, spleen, kidneys, trachea, bronchi, urinary bladder, heart, left and right aortas, and coelomic cavity were macroscopically inspected; organs and tissues were removed and washed through a sieve. A search for parasites was made using a stereoscopic microscope; recovered parasites were fixed and stored in 70% alcohol until staining and identification. Prevalence, mean intensity, and mean abundance values were recorded. In total, 156 parasite specimens belonging to 9 species were found: nematodes included Anisakis simplex s.l. (larvae) and an unidentified species; digenetic trematodes present were Enodiotrema megachondrus, Rhytidodes gelatinosus, Pyelosomum renicapite, and Calycodes anthos; acanthocephalans included Bolbosoma vasculosum and Rhadinorhynchus pristis; a single cestode, Nybelinia sp., was present. Parasite infections were found to have both low prevalences and intensities. Possible reasons for this include the oligotrophic conditions of the pelagic habitat around Madeira; a 'dilution effect' because of the vastness of the area; and the small size, and thus ingestion rate, of the turtles. Results are discussed in terms of the various turtle populations that may use the waters surrounding Madeira. This work provides valuable information on the parasite fauna of a poorly known stage in the life of loggerhead sea turtles, thereby filling a fundamental gap with regard to features of the parasite fauna in this species.