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  • ItemAcesso Aberto
    Environmental and bioclimatic factors influencing yeasts and molds distribution along European shores
    2023-02 - Cogliati, M.; Arikan-Akdagli, S.; Barac, A.; Bostanaru, A.C.; Brito, S.; Çerikçioğlu, N.; Efstratiou, M.A.; Ergin, Ç.; Esposto, M.C.; Frenkel, M.; Gangneux, J.P.; Gitto, A.; Gonçalves, C.I.; Guegan, H.; Gunde-Cimerman, N.; Güran, M.; Jonikaitė, E.; Kataržytė, M.; Klingspor, L.; Mares, M.; Meijer, W.G.; Melchers, W.J.G.; Meletiadis, J.; Nastasa, V.; Babič, M. Novak; Ogunc, D.; Ozhak, B.; Prigitano, A.; Ranque, S.; Romanò, L.; Rusu, R.O.; Sabino, R.; Sampaio, Ana C.; Silva, S.; Stephens, J.H.; Tehupeiory-Kooreman, M.; Velegraki, A.; Veríssimo, C.; Segal, E.; Brandão, J.
    The present study employed data collected during the Mycosands survey to investigate the environmental factors influencing yeasts and molds distribution along European shores applying a species distribution modelling approach. Occurrence data were compared to climatic datasets (temperature, precipitation, and solar radiation), soil datasets (chemical and physical properties), and water datasets (temperature, salinity, and chlorophyll-a concentration) downloaded from web databases. Analyses were performed by MaxEnt software.Results suggested a different probability of distribution of yeasts and molds along European shores. Yeasts seem to tolerate low temperatures better during winter than molds and this reflects a higher suitability for the Northern European coasts. This difference is more evident considering suitability in waters. Both distributions of molds and yeasts are influenced by basic soil pH, probably because acidic soils are more favorable to bacterial growth. Soils with high nitrogen concentrations are not suitable for fungal growth, which, in contrast, are optimal for plant growth, favored by this environment. Finally, molds show affinity with soil rich in nickel and yeasts with soils rich in cadmium resulting in a distribution mainly at the mouths of European rivers or lagoons, where these metals accumulate in river sediments.
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    Mycotoxins and other secondary metabolites are produced by Gnomoniopsis smithogilvyi when confronted with Biological and Chemical Control Agents
    2023-05-30 - Álvarez, Micaela; Agostini, Isadora; Silva, Sofia; Dallemole-Giaretta, Rosangela; Sulyok, Michael; Sampaio, Ana C.; Rodrigues, Paula
    Gnomoniopsis smithogilvyi (Gs) is a relevant pathogen of chestnut since it provokes significant losses worldwide. The aim of this study was to screen the effect of a new biocontrol agent (BCA) against Gs isolated from chestnut (CIMO-BCA1) on the mould’s growth as well as on the production of secondary metabolites. The chemical fungicide Horizon® (tebuconazole; HOR) and the commercial biofungicide Serenade® ASO (Bacillus amyloliquefaciens QST 713; ASO) were also tested. Three concentrations of each antifungal (HOR, ASO, and CIMO-BCA1) were faced with Gs in the growth study in a chestnut-based medium. The intermediate concentrations were used for the analyses of metabolites by LC-MS/MS. CIMO-BCA1 was also identified as B. amyloliquefaciens. All agents reduced the mould’s growth, and the CIMO-BCA1 treatment with an intermediate concentration was the most effective. The metabolite analysis revealed, for the first time, the production of two mycotoxins by Gs, including 3-nitropropionic acid and diplodiatoxin. Additionally, HOR stimulated the production of diplodiatoxin. In conclusion, Gs could present a health risk for consumers. B. amyloliquefaciens strains effectively decreased the mould’s growth, but they must be applied at effective concentrations or in combination with other strategies to completely reduce the hazard.
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    Chestnut Brown Rot and Gnomoniopsis smithogilvyi: Characterization of the Causal Agent in Portugal
    2023-03-24 - Possamai, Guilherme; Dallemole-Giaretta, Rosangela; Laranjo, José Carlos Esteves Gomes; Sampaio, Ana C.; Rodrigues, Paula
    Sweet chestnut (Castanea sativa Miller) is a nutritious food with high social and economic impacts in Portugal. The fungus Gnomoniopsis smithogilvyi (syn. Gnomoniopsis castaneae) is the causal agent of chestnut brown rot, and is currently considered one of the major threats to the chestnut production chain worldwide. Considering the lack of knowledge on both the disease and the causal agent in Portugal, studies were conducted in an attempt to develop the necessary control strategies towards the mitigation of the disease in a timely way. Isolates of G. smithogilvyi were selected from three varieties of chestnut from the northeast of Portugal, and were characterized at the morphological, ecophysiological and molecular levels. Tests of pathogenicity and virulence were also developed. Gnomoniopsis smithogilvyi was confirmed as the causal agent of brown rot disease in Portuguese chestnut varieties, which showed high susceptibility. The fungus showed high adaptability to chestnut substrates. The Portuguese isolates of G. smithogilvyi are morphologically and genetically similar to those from other countries, even though some physiological variability was observed among them.
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    Solid-State Fermentation of Chestnut Shells and Effect of Explanatory Variables in Predictive Saccharification Models
    2022-02-23 - Pinto, Paula A.; Bezerra, Rui Manuel Furtado; Fraga, Irene; Amaral, Carla; Sampaio, Ana C.; Dias, Albino A.
    In this study, chestnut shells (CNS), a recalcitrant and low-value agro-industrial waste obtained during the peeling of Castanea sativa fruits, were subjected to solid-state fermentation by six white-rot fungal strains (Irpex lacteus, Ganoderma resinaceum, Phlebia rufa, Bjerkandera adusta and two Trametes isolates). After being fermented, CNS was subjected to hydrolysis by a commercial enzymatic mix to evaluate the effect of fermentation in saccharification yield. After 48 h hydrolysis with 10 CMCase U mL−1 enzymatic mix, CNS fermented with both Trametes strains was recorded with higher saccharification yield (around 253 mg g−1 fermented CNS), representing 25% w/w increase in reducing sugars as compared to non-fermented controls. To clarify the relationships and general mechanisms of fungal fermentation and its impacts on substrate saccharification, the effects of some independent or explanatory variables in the production of reducing sugars were estimated by general predictive saccharification models. The variables considered were lignocellulolytic activities in fungal fermentation, CNS hydrolysis time, and concentration of enzymatic hydrolysis mix. Multiple linear regression analysis revealed a very high significant effect (p < 0.0001) of fungal laccase and xylanase activities in the saccharification models, thus proving the key potential of these enzymes in CNS solid-state fermentation.
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    Vibrio spp.: Life Strategies, Ecology, and Risks in a Changing Environment
    2022-01-29 - Sampaio, Ana C.; Silva, Vanessa; Poeta, Patricia Alexandra Curado Quintas ...; Aonofriesei, Florin
    Vibrios are ubiquitous bacteria in aquatic systems, especially marine ones, and belong to the Gammaproteobacteria class, the most diverse class of Gram-negative bacteria. The main objective of this review is to update the information regarding the ecology of Vibrio species, and contribute to the discussion of their potential risk in a changing environment. As heterotrophic organisms, Vibrio spp. live freely in aquatic environments, from marine depths to the surface of the water column, and frequently may be associated with micro- and macroalgae, invertebrates, and vertebrates such as fish, or live in symbiosis. Some Vibrio spp. are pathogenic to humans and animals, and there is evidence that infections caused by vibrios are increasing in the world. This rise may be related to global changes in human behavior (increases in tourism, maritime traffic, consumption of seafood, aquaculture production, water demand, pollution), and temperature. Most likely in the future, Vibrio spp. in water and in seafood will be monitored in order to safeguard human and animal health. Regulators of the microbiological quality of water (marine and freshwater) and food for human and animal consumption, professionals involved in marine and freshwater production chains, consumers and users of aquatic resources, and health professionals will be challenged to anticipate and mitigate new risks.
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    Two better than one: The complementary of different types of artificial substrates on benthic marine macrofauna studies
    2021 - Carreira-Flores, Diego; Neto, Regina; Ferreira, Hugo; Cabecinha, Edna; Díaz-Agras, Guillermo; Gomes, Pedro T.
    Non-destructive methodologies based on the use of artificial substrates (AS) for quantitative sampling of mac-rofauna have been used to solve sampling problems in complex benthic environment, such as rocky reefs. The macrofauna assemblages of two different types of AS (dendritic and crevice), at two different locations were studied. The main goal was to evaluate the complementarity of dendritic and crevice AS when sampling the macrofauna associated with rocky environments, in two scenarios: within the same location and between lo-cations. With this approach, we intend to contribute to the development of a non-destructive sampling meth-odology based on AS. The hypotheses tested were that i) the assemblages associated with each type of AS would differ between them and, ii) regardless of AS type, assemblages would differ between locations. Our results revealed significant differences after three months between the macrofauna assemblages from dendritic and crevice substrates in both locations and differences between locations irrespective of the AS type used. Hence, due to the high number of species that only were attracted by each type of AS and the species settlement preferences, our findings have shown the complementarity of the two types of AS (dendritic and crevice). This suggests that the mixed use of AS could be the best approach to non-destructive standard monitoring programs based on benthic marine macrofauna.
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    Effect of soil mineralogy on potassium fixation in soils developed on different parent material
    2019 - Portela, Ester; Monteiro, Fernando; Fonseca, Madalena; Abreu, Maria Manuela
    Potassium release from weathering of soil minerals may support the K nutrition of crops for many years. However, when soils become exhausted, the response to K fertilisation may be limited due to its fixation in nonexchangeable forms, reducing the efficacy of K fertilisation. The present study examines the role of soil mineralogical composition on the K fixation characteristics of soils developed under a Mediterranean type of climate. Nine soils derived from different parent materials were collected in several regions of Portugal. Soil properties were determined, and clay, silt and fine-sand fractions were studied by X-ray diffraction. Potassium fixation was determined after the soil samples had been treated with increasing rates of K application. The amount of K fixed was obtained by difference, measuring the amount of K remaining extractable by ammonium acetate. The soils under study showed a relatively high K fixation capacity, varying between 30 and 80% for an application rate equivalent to 800kgKha−1. Soils with high K fixation capacity were derived from gabbros, gabbrodiorites and quarzdiorites, and had relevant amounts of vermiculites and/or interstratified mica-vermiculite minerals, either in the clay or in the silt and fine sand fractions. Soils rich in calcium carbonates also fix high amounts of K. These soils contain mica-illite minerals and are rich in some of the above-mentioned minerals in the clay and silt fractions. While K fixation capacity is normally assumed to derive from minerals in the clay fraction, the results of this study show that vermiculites and/or interstratified mica-vermiculites presentin the silt and finesand fractions can contribute asignificant proportion of the total K fixation capacity and, thus, these size fractions should also be included in any assessment of K fixation capacity.
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    How informative is the response of Ground Beetles' (Coleoptera: Carabidae) assemblages to anthropogenic land use changes? Insights for ecological status assessments from a case study in the Neotropics
    2018 - Cajaiba, Reinaldo Lucas; Périco, Eduardo; Silva, Wully Barreto da; Vieira, Thiago Bernadi; Dalzochio, Marina Schmidt; Bastos, Rita; Cabral, João Alexandre Ferreira Abel Dos ...; Santos, Mario Gabriel Santiago Dos
    Ground Beetles (Carabidae) have been suggested to be used as indicators of ecological status under the effects of anthropogenic land use and land cover changes in highly biodiverse regions such as the Neotropics. In this study Ground Beetles' assemblages from a region in the Brazilian Amazon were investigated for evaluating their applicability as disturbance indicators. Differences in assemblages between ecosystems, discriminated by complimentary methodologies, demonstrate a sensitive reaction from the most pristine forests to increasingly disturbed systems. Besides capturing the influence of different prevailing conditions between ecosystems, Ground Beetles are easy to communicate and to link with the other components of the system, being effortless and routinely measurable using standard methodologies. This study represents a step forward in using Ground Beetles for the purposes of planning, management and public reporting on the ecological status of Neotropical ecosystems. Additionally, the methods depicted could support projections for trends of relevant ecosystem attributes under realistic social-ecological change scenarios, which can be used to guide effective conservation planning.
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    Attraction of Scarabaeinae (Coleoptera: Scarabaeidae) to different baits in the Brazilian Amazon region,Atracción de Scarabaeinae (Coleoptera: Scarabaeidae) por diferentes cebos en la región Amazónica Brasileña
    2017-09 - Cajaiba, Reinaldo L.; Périco, Eduardo; Silva, Wully B. da; Santos, Mario Gabriel Santiago Dos
    Dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) are considered essential for enhancing the physicochemical characteristics of soils, principally by changing organic materials (e.g. dead animals, faeces, fruits e leaf litter). This study compared the species richness and abundance of dung beetles captured using various types of baits, to demonstrate attractiveness differences in variable habitats of the Brazilian Amazon. Samplings were carried out with pitfall traps baited with human faeces, rotten banana, rotten meat and a nonbaited trap, in February, March, June, September and October 2015. Habitats included native forests, agriculture areas, pastures and disturbed forests in different regeneration stages. A total of 13 736 Scarabaeinae beetles were captured, distributed over 98 species. Most individuals were captured using traps baited with faeces (76.7 % of individuals), followed by rotten meat baited traps (17.8 % of individuals), fermented banana baited traps (3.9 % of individuals) and finally by non-baited traps (1.6 % of individuals). A significant difference in attractiveness of the different baits used and habitats types was observed. Most of the captured assemblages were composed by coprophagous (42 %), generalist species (32 %), necrophagous (15 %) and none was classified as saprophagous. Approximately 54 % of the specimens were tunnelers, 25 % were rollers and 12 % were dwellers. The species of Scarabaeinae sampled in the region revealed qualitative and quantitative differences among their assemblages and the phytophysiognomies. The forest environments housed the greatest species richness observed, and a fraction of these is exclusive of those areas. We concluded that some species of Scarabaeinae have an important potential as disturbance indicators in the Amazonian ecosystem. Rev. Biol. Trop. 65 (3): 917-924. Epub 2017 September 01.
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    Do the passerine traits’ dynamic patterns indicate the ecological status of agro-forestry ecosystems? A modelling approach for “Montado¿? management assessments
    2016 - Mulatu, Tilahun; Bastos, Rita; Santos, Mario Gabriel Santiago Dos; Sousa, José Paulo; Silva, Pedro Martins da; Cabral, João Alexandre Ferreira Abel Dos ...
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    Potassium supplying capacity of northeastern Portuguese soils
    1993 - Portela, Ester
    In Portugal, the response to K application is often inconsistent with the Egner-Riehm values for available K. This is partly related to high K reserves of some soils. Twenty surface soils representative of different parent materials from NE Portugal were studied to determine their K supplying capacity. Continuous cropping with perennial ryegrass permitted the assessment of the relative ability of soils to release non-exchangeable K. Soils were classified in the range of available K from medium to very high. However, their ability to supply K in the short and long term are very different. In some soils K status measured by plant growth does not fall appreciably, whilst others are rapidly exhausted, and 30% of them are very deficient in K. The supplying capacity varied both with the nature of the parent material and the degree of weathering. The soils deficient in K are those derived from basic rocks and those with more weathered clay minerals. This is the case of the soils with the largest content of organic matter where the dominant clay minerals were kaolinite and vermiculite. Soils that have the highest capacity for supplying K are highly micaceous, like those developed from mica schists, phyllites or river alluvium. In fact the amount of K released from non-exchangeable form is well correlated with the amount of illite in the clay fraction. Soil types and K buffer power coupled with available K must be taken into account when planning any application of K.
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    Boron application on a chestnut orchard: effect on yield and quality of nuts
    2011 - Portela, Ester; Louzada, José
    Although boron (B) deficiency in chestnuts (Castanea sativa Mill.) has been identified in Portugal and B fertilization was carried out in some orchards, the post-treatment evaluations have not been made to date. So the objective of this trial was to confirm the B deficiency and to quantify the effect of B applications to the soil on nut yield and quality. In October 2006, a fertilizer trial was established in a 15 year-old orchard in a very acid soil derived from siliceous schists. Soil liming and a basal fertilization were carried out in 16 trees and two levels of sodium tetraborate (Granubor, 14.6% B) were applied to eight trees: control (B0) and 100 g of Granubor per tree (B1). In the beginning of September chestnut leaves were collected from five trees and analyzed for macroand micronutrients. Nut productivity was measured per tree and some nut quality parameters were evaluated, including the chemical composition of the kernel (soluble sugars, starch, total fiber, crude protein, and crude fat) in 2007, and dry matter, nut caliber, and fruit damage in 2007 and 2008. Boron fertilization of chestnuts significantly increased nut production: 75% in the first year (8 kg and 14 kg per tree, respectively, in the B0 and B1) and, in the second year, was over four times higher (4 kg and 17 kg per tree, respectively, in the B0 and B1). No significant differences were found in dry matter, nut caliber, nut damage and chemical composition of the kernel in the first year, but in the second year lower fruit damage by chestnut tortrix (P<0.0089) was observed. Foliar analyses exhibit relatively low B concentrations in the control trees (average value of 8 mg kg −1 ) in both years, while in the fertilized trees the foliar B concentration were in average 61 mg kg −1 in the first year, and 34 mg kg −1 in the second year. The large drop in the foliar B concentration in the second year suggests the need to monitoring the nutrient status of chestnut orchards or more frequente of B application than usual practice.
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    Early diagnosis of boron deficiency in chestnut
    2012 - Portela, Ester; Louzada, José
    This study aims to identify an alternative plant tissue to be used in the early diagnosis of boron (B) deficiency in chestnut (Castanea sativa Mill.). A B-deficient orchard was selected, and 16 trees were submitted to two levels of B fertilization. When flowers were in bloom, the following tissues were sampled: leaves, androgynous catkins and flowers. There was a significant increase in B content in plant tissues due to B application. In July, the highest B content was observed in flowers in B0, but leaves had the greatest content in B1. Boron content in the tissues collected in July was positively correlated with B contents in leaves sampled in September. Foliar B concentrations, irrespective of the sampling period, were correlated with chestnut productivity, while the other tissues did not. These results suggest that the leaves, sampled in bloom, were the most efficient tissue for the early diagnosis of B deficiency
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    Deficiências de magnésio em solos e culturas do norte de Portugal
    2007 - Portela, Ester; Louzada, José
    Diversos estudos realizados no norte de Portugal têm alertado para o ocorrência de carências de magnésio ou para a possibilidade de deficiente nutrição magnesiana nalgumas culturas. A partir de Julho-Agosto, pode observar-se a sintomatologia de carência de Mg em diversas zonas daquela região em culturas como o milho, em arbóreas e arbustivas, e ainda em espécies florestais. Em Trás-os Montes e Alto Douro e no Entre-Douro e Minho as deficiências de Mg nas culturas têm-se observado sobretudo em solos desenvolvidos em xistos do Silúrico e do Ordovício, em xistos do Precâmbrico e Câmbrico do complexo Xisto-grauváquico e em solos provenientes de granitos predominantemente alcalinos de duas micas. Nas formações silúricas, ordovícias e do complexo Xisto-grauváquico dominam as seguintes litologias: quartzofilitos feldspáticos, filitos, micaxistos, xistos grafitosos, ampelitos, liditos, psamitos, grauvaques, siltitos e, ainda, quartzitos xistóides e quartzitos. As unidades-solo onde, frequentemente, se tem observado baixas concentrações foliares de Mg, ou mesmo sintomas da carência de Mg são: os Cambissolos e Leptossolos úmbricos; os Cambissolos e Leptossolos dístricos; os Regossolos úmbricos; os Fluvissolos dístricos e úmbricos; e, ainda, os Antrossolos úmbricos, cumúlicos e áricos. Alguns dos dados aqui apresentados foram coligidos, não só em estudos em que o principal objectivo foi o da confirmação da deficiência de Mg, mas também em levantamentos do estado nutritivo de diversas culturas. Na maioria dos estudos utilizou-se como método de diagnóstico as concentrações foliares de Mg, mas também foram identificadas razões entre nutrientes, nomeadamente Mg/N e Mg/K, associadas à carência de Mg. Nalguns deles determinou-se o limiar a partir do qual se observaram as deficiências de Mg. Em quase todos os trabalhos se acharam correlações entre as concentrações foliares de Mg e diversos parâmetros químicos do solo, como os teores de Mg na solução do solo e o Mg de troca, com as razões Mg/K, Mg/Ca, Mg/Ca+Mg, Mg/Ca+Mg+K, Mg/CTC, Mg/NH4 e Mg/Al+H, ou com o efeito combinado destas razões. A carência de Mg parece ser clássica em solos ácidos provenientes de material originário pobre em Mg, mas também pode ser despoletada por factores locais, ou por práticas culturais desajustadas.
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    Liming and application of nitrogen, phosphorus, potassium,and boron on a young plantation of chestnut
    2017 - Arrobas, Margarida; AFONSO, Sandra; Ferreira, Isabel Q.; Moutinho-Pereira, José; Correia, Carlos M.; Rodrigues, M. Ângelo
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    Dynamic models in research and management of biological invasions
    2017 - Buchadas, Ana; Vaz, Ana Sofia; Honrado, João P.; Alagador, Diogo; Bastos, Rita; Cabral, João A.; Santos, Mário; Vicente, Joana R.
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    A spatially-explicit dynamic modelling framework to assess habitat suitability for endangered species: The case of Red-billed Chough under land use change scenarios in Portugal
    2017 - Morinha, Francisco; Bastos, Rita; Carvalho, Diogo; Travassos, Paulo; Santos, Mário; Blanco, Guillermo; Bastos, Estela; Cabral, João A.
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    Does the composition of Scarabaeidae (Coleoptera) communities reflect the extent of land use changes in the Brazilian Amazon?
    2017 - Cajaiba, R.L.; Péricoa, E.; Dalzochioa, M.S.; Silva, W.B.; Bastos, R.; Cabral, J.A.; Santos, M.