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- Profiling of lipophilic and phenolic phytochemicals of four cultivars from cherimoya (Annona cherimola Mill.)Publication . Santos, Sónia A. O.; Vilela, Carla; Camacho, João F.; Cordeiro, Nereida; Gouveia, Manuela; Freire, Carmen S. R.; Silvestre, Armando J.D.The lipophilic and phenolic extractives of the ripe mesocarp of four cherimoya cultivars ('Perry Vidal', 'Mateus I', 'Mateus III' and 'Funchal') from Madeira Island, were studied for the first time. The predominant lipophilic compounds are kaurene diterpenes (42.2-59.6%), fatty acids (18.0-35.6%) and sterols (9.6-23.7%). Kaur-16-en-19-oic acid is the major lipophilic component of all cultivars accounting between 554 and 1350mgkg(-1) of dry material. The studied fruits also contain a high variety of flavan-3-ols, including galloylated and non-galloylated compounds. Five phenolic compounds were identified for the first time: catechin, (epi)catechin-(epi)gallocatechin, (epi)gallocatechin, (epi)afzelechin-(epi)catechin and procyanidin tetramer. 'Mateus I' and 'Mateus III' cultivars present the highest content of phenolic compounds (6299 and 9603mgkg(-1) of dry weight, respectively). These results support the use of this fruit as a rich source of health-promoting components, with the capacity to prevent or delay the progress of oxidative-stress related disorders.
- Molecular cloning and characterization of cDNA encoding a Translocon-Associated Protein (TRAPδ) from the root-lesion nematode Pratylenchus goodeyiPublication . Pestana, Margarida; Abrantes, Isabel M. de O.; Gouveia, ManuelaThe translocon-associated protein (TRAP) complex comprises four subunits (α, β, γ, δ) and is located in the endoplasmic reticulum membrane at translocation sites. The TRAP complex is required for the efficient translocation of substrates and to correct or eliminate misfolded proteins. In this study, we described the cloning and characterization of a cDNA encoding a TRAP from the phytoparasitic nematode Pratylenchus goodeyi (Pg). The full-length cDNA had an estimated size of 690 bp and encodes a 177 amino acid peptide. The deduced protein after sequence analysis codes for TRAPδ subunit homologous to TRAPδ from other nematodes. The Pg-TRAPδ had a signal peptide indi cating a possible involvement in the transport and binding of other proteins at the endoplasmic reticulum membrane. The increase in relative expression of Pg trapδ, assessed by semi-quantitative PCR, was induced over time in nematodes exposed to a nematostatic/ nematicide extract of Solanum nigrum, suggesting that this gene product might be influenced by response mechanisms to stress in P. goodeyi. This is the first report of the cloning and characterization of trap cDNA from plant endoparasitic nematodes.
- Population decline in the critically endangered Musschia isambertoi (Campanulaceae) endemic to Desertas Islands (Madeira Archipelago) calls for urgent conservation managementPublication . Sequeira, M. Menezes de; Jardim, R.; Gouveia, M.; Góis-Marques, C. A.; Eddie, W. M. M.Macaronesian islands display a high degree of plant endemicity and correspond to some of the most threatened biodiversity hotspots due to several human driven impacts such as habitat loss, invasive species, overexploitation or climate change. The conservation status of the largest of the two known population of Musschia isambertoi M. Seq., R. Jardim, Magda Silva and L. Carvalho (Campanulaceae) was assessed recently. Field work was done in June 2018 in “Porto das Moças” Deserta Grande (Madeira Archipelago, Portugal), the locus typicus, where in 2006 close to 30 plants were detected with a high variation of age/size between individuals comprising both fully flowering and non-flowering adult plants as well as seedlings, and thus corresponding to a healthy population. This study assesses population size, age and plant size, and genetic, as well as floristic diversity. The total area of the site corresponds to approximately 1500 square meters. Ten individuals were detected, all corresponding to young seedlings not exceeding 15 cm high, and exhibiting approximately the same size and numbers of leaves (4–8). No adult plants or remains of adult plants were seen. Ecological data and direct herbivory evidence suggest that perennial plants are subjected to elimination during the short summer by the feral goat population. Mo lecular data based on ISSR markers show that the nine sampled individuals (out of ten individuals found) are genetically identical, possibly resulting from one parental plant. Results clearly suggest that Musschia isambertoi is very close to extinction. Urgent conservation measures are imperative and should include the immediate fencing of the population followed by the elimination of feral goats from Deserta Grande. The elimination of feral goats was initiated in 1996 (LIFE95 NAT/P/000125, 383,467.00 €) but stopped due to inappropriate conser vation policies of the former Services of the Natural Park of Madeira.
- Extinctions of introduced game species on oceanic islands: curse for hunters or conservation opportunities?Publication . Rocha, Ricardo; Sequeira, Miguel M.; Douglas, Leo R.; Gouveia, Manuela; Jardim, Roberto; Jesus, José; Jones, Holly P.; Russo, Danilo
- In vitro evaluation of nematicidal properties of Solanum sisymbriifolium and S. nigrum extracts on Pratylenchus goodeyiPublication . Pestana, Margarida; Rodrigues, Mónica; Teixeira, Lucília; Abrantes, Isabel de O.; Gouveia, Manuela; Cordeiro, NereidaThe root-lesion nematode, Pratylenchus goodeyi, is among the most economically damaging parasites of banana plants. Nematode control can benefit from searching for novel bio-nematicides. The present study was carried out to assess the potential nematicidal properties of two Solanum species (Solanum sisynibriífolíum and S. nigrum) against P. goodeyi, using dichloromethane, acetone, ethanol and either cold or hot water extracts of the plants. Water extracts of both plants at a concentration of 10 mg ml" ' greatly affected nematode movement and also caused mortality. The analysis of sequential extracts at the same experimental concentrations showed that, although water extracts affect nematode mobility and mortality, the acetone extract from S. nigrum was the most efficient, causing 100% mortality after 23 h exposure. The results showed that S. sísymbríífolíum and S. nigrum extracts contain chemical components that induce morphological changes in the body structure of the root-lesion nematode, affect mobihty and cause mortality. The nematostatic and nematicidal potential of the extracts described herein merit further studies to find novel bio-nematicides against the root-lesion nematode.
- Genetic diversity in Hemileia vastatrixbased on RAPD markersPublication . Gouveia, M. Manuela C.; Ribeiro, Ana; Várzea, Vítor M. P.; Rodrigues Jr., Carlos J.Random amplified polymorphic DNA (RAPD) was used to assess the genetic structure of Hemileia vastatrix populations. Forty-five rust iso lates with different virulence spectra and from dif ferent hosts and geographical regions were ana lyzed. Out of 45 bands, generated with three RAPD primers, 35 (78%) were polymorphic and scored as molecular markers. Cluster analysis exhibits unstruc tured variability of this pathogen with regard to physiological race, geographical origin or host. The genotypic diversity (H9) inferred from Shannon’s in dex was higher than gene diversity (Ht), suggesting that diversity is distributed among clonal lineages. Estimates of gene diversity in Africa and Asia pop ulations were higher in total (Ht) as compared to within population diversity (Hs). Genetic differen tiation was considerable among coffee rust isolates from Africa (Gst 5 0.865) and Asia (Gst 5 0.768) but not among isolates from South America (Gst 5 0.266). We concluded that genetic diversity in H. vastatrix was moderately low and that the genetic differentiation among populations shows that asex ual reproduction is likely to play an important role in the population biology of this fungus. This should be taken into account for the development of breed ing programs.
- Molecular, morphological and agronomic characterization of the sweet potato (Ipomoea batatas L.) germplasm collection from Mozambique: Genotype selection for drought prone regionsPublication . Maquia, I.; Muocha, I.; Naico, A.; Martins, N.; Gouveia, M.; Andrade, I.; Goulao, L. F.; Ribeiro, A. I.Sweet potato (Ipomoea batatas (L.) Lam) is one of the most important root crops in Mozambique, ranking in the 3rd position, after cassava and maize. Within the scope of the national and regional strategies/initiatives, we have used a multi-analysis approach to characterize the national sweet potato germplasm collection at two different levels: i) genetic, morphological and agronomic diversity; and ii) agronomic potential (storage root yield, vine weight, biomass, harvest index and dry matter content) toward drought tolerance. This collection, composed by 44 accessions, comprises 28 genotypes cultivated in three different provinces of Mozambique (Gaza, Inhambane and Zambezia), nine from other African countries (Kenya, South Africa, Uganda and Zimbabwe), one from the United States of America, and six from CGIAR research centers (IITA and CIP). According to our results, the Mozambican germplasm bank presents a high level of diversity, comparable to those from the collections of the primary centers of origin and South Africa, therefore constituting of a good source of agronomic traits for breeding. Regarding drought tolerance, six Mozambican genotypes (Admarc, Chingova, Nhacoongo-1, Xihetamakote, Nwanatuyo, and Chissicuana-2), one from Uganda (NASPOT-5), one from Zimbabwe (Moz_white), one from Kenya (SPK 004), and one from the USA (Resisto) seem to have the highest potential to be used in regions with frequent drought seasons and in future breeding programs. The results showed that such integrated analysis can be used to successfully characterize the genetic material in terms of suitability to drought-prone regions, there fore helping sweet potato crop management, with economic and food security impacts.
- The Madeiran laurel forest endemic Goodyera macrophylla (Orchidaceae) is related to American orchidsPublication . Thiv, Mike; Gouveia, Manuela; Sequeira, Miguel Menezes deMacaronesian laurel forests harbour many herbs and lauro phyllous trees with Mediterranean/European or Macaronesian affini ties. Traditionally, the origin of these taxa has been explained by the relict hypothesis interpreting these taxa as relics of formerly wide spread laurel forests in the European continent and the Mediterranean. We analysed the phylogenetic relationships of the Madeiran laurel forest endemic Goodyera macrophylla (Orchidaceae) using sequences from the nuclear ribosomal DNA Internal Transcribed Spacers (ITS) and plastid DNA regions. The results were incongruent, either the two Central American G. brachyceras and G. striata (ITS) or the North American G. oblongifolia (plastid DNA) were sister group to G. mac rophylla. Nonetheless, biogeographic analyses indicated an American origin of this nemoral laurel forest plant in the two data sets. Molecu lar clock analyses suggest a colonisation of Madeira in the span of the upper Miocene/lower Pliocene to the Pleistocene. Although the relict hypothesis cannot be ruled out by our data when assuming extinction events on the European and northern African mainland, dispersal from Central or North America to the archipelago of Madeira is a much more likely explanation of the data.
- Molecular cloning and characterization of cDNAs encoding cytosolic malate dehydrogenase and vacuolar (H+)-ATPase in Annona cherimola and their expression during postharvest ripeningPublication . Gouveia, Manuela; Rodrigues, Mónica; Teixeira, Lucília; Cordeiro, NereidaThis study aims to investigate the expression of two cherimoya genes putatively related to fruit ripening. Two full-length cDNAs encoding cytosolic NAD-dependent malate dehydrogenase (AccytMDH) and vacuolar (H+)-ATPase c subunit (AcVHA-c) were isolated from Annona cherimola using the reverse transcriptase polymerase chain reaction (RT- PCR) and rapid amplification of cDNA ends (RACE). The AccytMDH codes for a 332 amino acid polypeptide with a predicted molecular mass of 35.6 kDa. The deduced amino acid sequence for AccytMDH shared high identity with other plant homologous malate dehydrogenase proteins. The AcVHA-c encodes a proteolipid subunit of the V-type proton ATPase with 166 amino acids (16.7 kDa). Comparison of the deduced amino acid sequence from AcVHA-c revealed four transmembrane domains highly conserved among plant counterparts. The expression of AccytMDH and AcVHA-c, assessed by semi-quantitative RT-PCR showed that there is an increase in the accumulation of transcripts during postharvest ripening, although not correlated by a significant upsurge of titratable acidity they might contribute to organic acid accumulation and translocation during postharvest ripening of cherimoya in association with other enzymes and carriers. By using AccytMDH and AcVHA-c as molecular targets new strategies can be exploited to get a clear picture in the ripening of cherimoya.
- Intra-population genetic variability of Normania triphylla (Lowe) Lowe (Solanaceae) based on ISSR markersPublication . Gouveia, Manuela; Gonçalves, Filipa; Benedito, Micael; Sequeira, Miguel Menezes de