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- Biofortification of durum wheat (Triticum turgidum L. ssp durum (Desf.) Husnot) grains with nutrientsPublication . Pataco, Inês Maria; Lidon, Fernando Cebola; Ramos, Inês; Oliveira, Karliana; Guerra, Mauro; Pessoa, Maria Fernanda; Carvalho, Maria Luisa; Ramalho, José Cochicho; Leitão, António Eduardo; Santos, José Paulo; Campos, Paula Scotti; Silva, Maria Manuela; Pais, Isabel P.; Reboredo, Fernando Henrique; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; DCT - Departamento de Ciências da Terra; LIBPhys-UNL; DF – Departamento de Física; Taylor & FrancisDurum wheat (Triticum turgidum L. ssp. durum (Desf.) Husnot) was grown under conditions to promote mineral biofortification at the grain level. Along plant development, biomass accumulation and the kinetics of nutrients accumulation were assessed, identifying the nutrient fluxes of roots and shoots, and the timescale constraints of crop biofortification. Plants were grown under environmentally controlled conditions, submitted to four increasing concentrations of nutrient solutions (1-, 2-, 4- and 6-fold) of micro-(Fe, Zn, Cu and Mn) and macronutrients (Ca, K, P and Mg). The threshold of mineral toxicity was not reached as evaluated through plant biomass accumulation, but considering grain yield, the twofold nutrient concentration was the best treatment for biofortification. In the different treatments, the contents and the mineral unrests of roots uptake and shoots translocation varied, at different magnitudes and trends, before the onset of booting and from the physiological maturity onwards. Except for Cu, all mineral nutrients were mainly detected in the bran and embryo of the grains; therefore, the production of biofortified pasta for human consumption requires the use of integral semolina.
- New late Middle to early Late Ordovician U-Pb zircon ages of extension-related felsic volcanic rocks in the Eastern Pyrenees (NE Iberia): Tectonic implicationsPublication . Martí, Joan; Solari, Luigi; Casas, Josep Maria; Chichorro, Martim; DCT - Departamento de Ciências da Terra; Cambridge University PressPre-Variscan basement rocks from the Pyrenees provide evidence of several magmatic episodes with complex geodynamic histories from late Neoproterozoic to Palaeozoic times. One of the most significant episodes, consisting of several granitic and granodioritic bodies and volcanic rocks, mostly pyroclastic in nature, dates from the Late Ordovician period. In the Eastern Pyrenees, this magmatism is well represented in the Ribes de Freser and Núria areas; here, the Núria orthogneiss and the Ribes granophyre, both dated at c. 457-460 Ma, seem to form a calc-alkaline plutonic suite emplaced at different crustal levels. The presence of numerous pyroclastic deposits and lavas interbedded with Upper Ordovician (Sandbian-lower Katian, formerly Caradoc) sediments, intruded by the Ribes granophyre, suggests that this magmatic episode also generated significant volcanism. Moreover, the area hosts an important volume of rhyolitic ignimbrites and andesitic lavas affected by Alpine deformation. These volcanic rocks were previously attributed to late Variscan volcanism, extensively represented in other areas of the Pyrenees. Here we present the first five laser-ablation U-Pb zircon dates for this ignimbritic succession and two new ages for the Ribes granophyre. The ages of the ignimbrites, overlapping within error, are all 460 Ma, suggesting a genetic relationship between the plutonic and volcanic rocks and indicating that the Sandbian-Katian magmatism is much more voluminous than reported in previous studies, and possibly includes mega-eruptions linked to the formation of collapse calderas.
- Investigating Metals and Metalloids in Soil at Micrometric Scale Using µ-XRF SpectroscopyPublication . Barbosa, Sofia; Dias, António; Pacheco, Marta; Pessanha, Sofia; Almeida, J. António; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; DCT - Departamento de Ciências da Terra; DF – Departamento de Física; LIBPhys-UNL; MDPI - Multidisciplinary Digital Publishing InstituteMicrometric 2D mapping of distinct elements was performed in distinct soil grain-size fractions of a sample using the micro-X-ray Fluorescence (µ-XRF) technique. The sample was collected in the vicinity of São Domingos, an old mine of massive sulphide minerals located in the Portuguese Iberian Pyrite Belt. As expected, elemental high-grade concentrations of distinct metals and metalloids in the dependence of the existent natural geochemical anomaly were detected. Clustering and k-means statistical analysis were developed considering Red–Green–Blue (RGB) pixel proportions in the produced 2D micrometric image maps, allowing for the identification of elemental spatial distributions at 2D. The results evidence how elemental composition varies significantly at the micrometric scale per grain-size class, and how chemical elements present irregular spatial distributions in the direct dependence of distinct mineral spatial distributions. Due to this fact, elemental composition is more differentiated in coarser grain-size classes, whereas griding-milled fraction does not always represent the average of all partial grain-size fractions. Despite the complexity of the performed analysis, the achieved results evidence the suitability of µ-XRF to characterize natural, heterogeneous, granular soils samples at the micrometric scale, being a very promising investigation technique of high resolution.
- Remote Monitoring of Crop Nitrogen Nutrition to Adjust Crop ModelsPublication . Silva, Luís; Conceição, Luís Alcino; Lidon, Fernando Cebola; Maçãs, Benvindo; DCT - Departamento de Ciências da Terra; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; MDPI - Multidisciplinary Digital Publishing InstituteNitrogen use efficiency (NUE) is a central issue to address regarding the nitrogen (N) uptake by crops, and can be improved by applying the correct dose of fertilizers at specific points in the fields according to the plants status. The N nutrition index (NNI) was developed to diagnose plant N status. However, its determination requires destructive, time-consuming measurements of plant N content (PNC) and plant dry matter (PDM). To overcome logistical and economic problems, it is necessary to assesses crop NNI rapidly and non-destructively. According to the literature which we reviewed, it, as well as PNC and PDM, can be estimated using vegetation indices obtained from remote sensing. While sensory techniques are useful for measuring PNC, crop growth models estimate crop N requirements. Research has indicated that the accuracy of the estimate is increased through the integration of remote sensing data to periodically update the model, considering the spatial variability in the plot. However, this combination of data presents some difficulties. On one hand, at the level of remote sensing is the identification of the most appropriate sensor for each situation, and on the other hand, at the level of crop growth models is the estimation of the needs of crops in the interest stages of growth. The methods used to couple remote sensing data with the needs of crops estimated by crop growth models must be very well calibrated, especially for the crop parameters and for the environment around this crop. Therefore, this paper reviews currently available information from Google Scholar and ScienceDirect to identify studies relevant to crops N nutrition status, to assess crop NNI through non-destructive methods, and to integrate the remote sensing data on crop models from which the cited articles were selected. Finally, we discuss further research on PNC determination via remote sensing and algorithms to help farmers with field application. Although some knowledge about this determination is still necessary, we can define three guidelines to aid in choosing a correct platform.
- Soil Arsenic Toxicity Impact on the Growth and C-Assimilation of Eucalyptus nitensPublication . Ramalho, José C.; Pelica, João; Lidon, Fernando C.; Silva, Maria M. A.; Simões, Maria M.; Guerra, Mauro; Reboredo, Fernando H.; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; DCT - Departamento de Ciências da Terra; LIBPhys-UNL; DF – Departamento de Física; Molecular Diversity Preservation International (MDPI)The selection of adequate plants that can cope with species that can live in contaminated/degraded and abandoned mining areas is of utmost importance, especially for environmental management and policymakers. In this framework, the use of a fast-growing forestry species, such as Eucalyptus nitens, in the recovery of arsenic (As) from artificially contaminated soils during a long-term experiment was studied. Roots can accumulate to levels ranging between 69.8 and 133 μg g−1 for plants treated with 100 and 200 µg As mL−1, respectively, while leaves between 9.48 μg g−1 (200 As) and 15.9 μg g−1 (100 As) without apparent morphological damage and toxicity symptoms. The C-assimilation machinery performance revealed a gradual impact, as evaluated through some gas exchange parameters such as the net photosynthetic rate (Pn), stomatal conductance to H2O (gs), and transpiration rate (E), usually with the greater impacts at the highest As concentration (200 As), although without significantly impacting the PSII performance. The As effects on the uptake and translocation of Ca, Fe, K, and Zn revealed two contrasting interferences. The first one was associated with Zn, where a moderate antagonism was detected, whereas the second one was related to Fe, where a particular enrichment in leaves was noted under both As treatments. Thus, it seems to exist a synergistic action with an impact on the levels of the photosynthetic pigments in As-treated plant leaves, compared with control plants. E. nitens must be considered as an alternative when phytoremediation processes are put into practice in our country, particularly in areas with cool climatic conditions.
- Elemental Composition and Implications on Brown Rice Flour Biofortified with SeleniumPublication . Marques, Ana Coelho; Lidon, Fernando C.; Coelho, Ana Rita F.; Pessoa, Cláudia Campos; Daccak, Diana; Luís, Inês Carmo; Simões, Manuela; Scotti-Campos, Paula; Almeida, Ana Sofia; Guerra, Mauro; Leitão, Roberta G.; Bagulho, Ana; Moreira, José; Pessoa, Maria F.; Legoinha, Paulo; Ramalho, José C.; Semedo, José N.; Palha, Lourenço; Silva, Cátia; Silva, Maria Manuela; Oliveira, Karliana; Pais, Isabel P.; Reboredo, Fernando H.; DCT - Departamento de Ciências da Terra; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; LIBPhys-UNL; DF – Departamento de Física; MDPI - Multidisciplinary Digital Publishing InstituteRice (Oryza sativa L.) is one of the most economically and socially important cereals in the world. Several strategies such as biofortification have been developed in a way eco-friendly and sustainable to enhance crop productivity. This study implemented an agronomic itinerary in Ariete and Ceres rice varieties in experimental fields using the foliar application of selenium (Se) to increase rice nutritional value. At strategic phases of the plant’s development (at the end of booting, anthesis, and at the milky grain stage), they were sprayed with sodium selenate (Na2SeO4) and sodium selenite (Na2SeO3). In the first foliar application plants were sprayed with 500 g Se·ha−1 and in the remaining two foliar applications were sprayed with 300 g Se·ha−1. The effects of Se in the level of micro and macronutrients in brown grains, the localization of Se in these grains, and the subsequent quality parameters such as colorimetric characteristics and total protein were considered. After grain harvesting, the application of selenite showed the highest enrichment in all grain with levels reaching 17.06 µg g−1 Se and 14.28 µg g−1 Se in Ariete and Ceres varieties, respectively. In the Ceres and Ariete varieties, biofortification significantly affected the K and P contents. Regarding Ca, a clear trend prevailed suggesting that Se antagonizes the uptake of it, while for the remaining elements in general (except Mn) no significant differences were noted. Protein content increased with selenite treatment in the Ariete variety but not in Ceres. Therefore, it was possible to conclude, without compromising quality, that there was an increase in the nutritional content of Se in brown rice grain.
- Elemental composition, total fatty acids, soluble sugar content and essential oils of flowers and leaves of Moringa oleifera cultivated in Southern PortugalPublication . Monteiro, Josélia; Scotti-Campos, Paula; Pais, Isabel; Figueiredo, A. Cristina; Viegas, Dulce; Reboredo, Fernando; DCT - Departamento de Ciências da Terra; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; ElsevierThe evaluation of the elemental content of moringa leaves and flowers by Energy Dispersive X-Ray Fluorescence Spectrometry revealed that the leaves are a good source of some macro (Ca and K) and micronutrients (Mn) beyond the presence of important polyunsaturated fatty acids (PUFAs), essential in human nutrition. Total soluble sugars prevail in the flowers which may be linked to insect attraction and the pollination process. M. oleifera leaves, flowers and seeds essential oils (EOs) were isolated by hydrodistillation. Gas chromatography and gas chromatography-mass spectrometry analysis (GC-MS) showed EOs dominated by alkanes and fatty acids in diverse ratios in the analyzed plant parts. The nutritional characterization of M. oleifera cultivated in Portugal showed some important nutrients to human physiology. Further studies will allow determining if its consumption may overcome the nutritional imbalances of daily modern households, preventing the emergence of hypertension and diabetes.
- First occurrence of a frog-like batrachian (Amphibia) in the Late Triassic Fleming Fjord Group, centralPublication . Jesus, Valerian J. P.; Mateus, Octavio; Milan, Jesper; Clemmensen, Lars B.; DCT - Departamento de Ciências da Terra; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; Dansk Geologisk ForeningDuring the Triassic, Batrachia diverged into ancestors of frogs (Salientia) and salamanders (Caudata). Fossils of Triassic batrachians are rare and found only in a few outcrops, such as the Middle Sakamena Formation of Madagascar (Induan). Only three Triassic taxa have been described, the two early frogs Triadobatrachus and Czatkiobatrachus and the early salamander Triassurus. Here we describe a right ilium, collected in 1991, attributed to the first batrachian from the Late Triassic Carlsberg Fjord Member (Ørsted Dal Formation, Fleming Fjord Group) in the Jameson Land Basin, located in central East Greenland. The fossil specimen only displays the proximal part of a right ilium, missing its shaft. After a thorough comparison with several clades (lizards, temnospondyls, salamanders and frogs), we consider the specimen as a lissamphibian sharing feature with salientians and anurans: squarish acetabular region, deeply concave acetabular surface, laterally projecting acetabular rim, flat mesial surface. It is the youngest Triassic specimen of Batrachia to date and one of the northernmost of the Late Triassic.
- Multi-Target Alternative Approaches to Promoting Fresh-Cut Carrots’ Bioactive and Fresh-like QualityPublication . Alegria, Carla; Gonçalves, Elsa M.; Moldão-Martins, Margarida; Abreu, Marta; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; MDPI - Multidisciplinary Digital Publishing InstituteFresh-cut fruits and vegetables, as near-fresh foods, are a quick and easy solution to a healthy and balanced diet. The rapid degradation of nutritional and sensory quality during the processing and storage of a product is critical and plant-type-dependent. The introduction of disruptive technological solutions in fresh-cut processing, which could maintain fresh-like quality with less environmental impact, is an emerging research concept. The application of abiotic stress treatments (heat shock and UV-C) induces metabolic responses and microbial effects in plant tissues, potentially slowing down several quality senescence pathways. The previously selected combined and single effects of heat shock (100 °C/45 s; in the whole root) and UV-C (2.5 kJ/m2) treatments and two packaging conditions (oriented polypropylene (OPP) vs. micro-perforated OPP films) on controlling critical degradation pathways of fresh-cut carrots and on promoting bioactive and sensory quality during storage (5 °C, 14 days) were studied. Among the tested combinations, synergistic effects on the quality retention of fresh-cut carrots were only attained for applying heat shock associated with micro-perforated OPP film packaging. Its effects on reducing (3.3 Log10 CFU/g) the initial contamination and controlling microbiological spoilage (counts below the threshold limit of 7.5 Log10 CFU/g), increasing the bioactive content (38% and 72% in total phenolic content and chlorogenic acid, respectively), and preserving fresh quality attributes prove to be a viable alternative technology for shredded carrot processing.
- Salt Stress Tolerance in Casuarina glaucaPublication . Fernandes, Isabel; Paulo, Octávio S.; Marques, Isabel; Sarjkar, Indrani; Sen, Arnab; Graça, Inês; Pawlowski, Katharina; Ramalho, José C.; Ribeiro-Barros, Ana I.; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; MDPI - Multidisciplinary Digital Publishing InstituteClimate change and the accelerated rate of population growth are imposing a progressive degradation of natural ecosystems worldwide. In this context, the use of pioneer trees represents a powerful approach to reverse the situation. Among others, N2-fixing actinorhizal trees constitute important elements of plant communities and have been successfully used in land reclamation at a global scale. In this study, we have analyzed the transcriptome of the photosynthetic organs of Casuarina glauca (branchlets) to unravel the molecular mechanisms underlying salt stress tolerance. For that, C. glauca plants supplied either with chemical nitrogen (KNO3+) or nodulated by Frankia (NOD+) were exposed to a gradient of salt concentrations (200, 400, and 600 mM NaCl) and RNA-Seq was performed. An average of ca. 25 million clean reads was obtained for each group of plants, corresponding to 86,202 unigenes. The patterns of differentially expressed genes (DEGs) clearly separate two groups: (i) control- and 200 mM NaCl-treated plants, and (ii) 400 and 600 mM NaCl-treated plants. Additionally, although the number of total transcripts was relatively high in both plant groups, the percentage of significant DEGs was very low, ranging from 6 (200 mM NaCl/NOD+) to 314 (600 mM NaCl/KNO3+), mostly involving down-regulation. The vast majority of up-regulated genes was related to regulatory processes, reinforcing the hypothesis that some ecotypes of C. glauca have a strong stress-responsive system with an extensive set of constitutive defense mechanisms, complemented by a tight mechanism of transcriptional and post-transcriptional regulation. The results suggest that the robustness of the stress response system in C. glauca is regulated by a limited number of genes that tightly regulate detoxification and protein/enzyme stability, highlighting the complexity of the molecular interactions leading to salinity tolerance in this species.