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- Phenotypic evaluation of the IDC profile of soybean plants after inoculation with plant growth-promoting bacteriaPublication . Castro, Paula M. L.; Carvalho, Susana M. P.; Vasconcelos, Marta W.; Roriz, Mariana
- Study of the proximate and mineral composition of different Nigerian yam chips, flakes and floursPublication . Omohimi, C. I.; Piccirillo, C.; Roriz, M.; Ferraro, V.; Vasconcelos, M. W.; Sanni, L. O.; Tomlins, K.; Pintado, M. M.; Abayomi, L. A.Yam (Dioscorea spp) is an essential tuber crop for hundreds of millions of people in many African, Asian and South American countries. Considering in particular Southwest Nigeria, chips, flakes and flours are amongst the most common shelf-stable traditionally-processed yam products. This paper reports a systematic study on the proximate (moisture, protein, carbohydrate, fibre, fat, ash and gross energy) and mineral composition of these three food commodities sold in Nigerian markets. Results showed no significant differences in the moisture, crude protein and fibre content of all samples (10.0–12.3, 2.7–4.3 and 1.3–2.0 wt%, respectively). Gross energy was also comparable for all yam derived food items (between 3300 and 3507 kcal/kg), contradicting the common belief that yam flakes have lower nutritional value than chips and flours. Considering the mineral composition, Ca, Mg, P and K were the predominant macronutrients. Micronutrients such as Zn, Co, Mn and Cu were also detected. Significant differences existed between products, and their various sources (markets). Principal component analysis showed a direct correlation between ash content of the samples and the assessed macronutrients, irrespective of the market, or the seller of the commodities. This study confirmed that yam derived food stuffs have an adequate nutritional composition, irrespective of their form and/or origin.
- Chemical composition of red, brown and green macroalgae from Buarcos bay in Central West Coast of PortugalPublication . Rodrigues, Dina; Freitas, Ana C.; Pereira, Leonel; Rocha-Santos, Teresa A. P.; Vasconcelos, Marta W.; Roriz, Mariana; Rodríguez-Alcalá, Luís M.; Gomes, Ana M. P.; Duarte, Armando C.Six representative edible seaweeds from the Central West Portuguese Coast, including the less studied Osmundea pinnatifida, were harvested from Buarcos bay, Portugal and their chemical characterization determined. Protein content, total sugar and fat contents ranged between 14.4% and 23.8%, 32.4% and 49.3% and 0.6–3.6%. Highest total phenolic content was observed in Codium tomentosum followed by Sargassum muticum and O. pinnatifida. Fatty acid (FA) composition covered the branched chain C13ai to C22:5 n3 with variable content in n6 and n3 FA; low n6:n3 ratios were observed in O. pinnatifida, Grateloupia turuturu and C. tomentosum. Some seaweed species may be seen as good sources of Ca, K, Mg and Fe, corroborating their good nutritional value. According to FTIR-ATR spectra, G. turuturu was associated with carrageenan seaweed producers whereas Gracilaria gracilis and O. pinnatifida were mostly agar producers. In the brown algae, S. muticum and Saccorhiza polyschides, alginates and fucoidans were the main polysaccharides found.
- Effect of tris(3-hydroxy-4-pyridinonate) iron(III) complexes on iron uptake and storage in soybean (Glycine max L.)Publication . Santos, Carla S.; Carvalho, Susana M.P.; Leite, Andreia; Moniz, Tânia; Roriz, Mariana; Rangel, António O. S. S.; Rangel, Maria; Vasconcelos, Marta W.Iron deficiency chlorosis (IDC) is a serious environmental problem affecting the growth of several crops in the world. The application of synthetic Fe(III) chelates is still one of the most common measures to correct IDC and the search for more effective Fe chelates remains an important issue. Herein, we propose a tris(3-hydroxy-4-pyridinonate) iron(III) complex, Fe(mpp)3, as an IDC corrector. Different morphological, biochemical and molecular parameters were assessed as a first step towards understanding its mode of action, compared with that of the commercial fertilizer FeEDDHA. Plants treated with the pyridinone iron(III) complexes were significantly greener and had increased biomass. The total Fe content was measured using ICP-OES and plants treated with pyridinone complexes accumulated about 50% more Fe than those treated with the commercial chelate. In particular, plants supplied with compound Fe(mpp)3 were able to translocate iron from the roots to the shoots and did not elicit the expression of the Fe-stress related genes FRO2 and IRT1. These results suggest that 3,4-HPO iron(III) chelates could be a potential new class of plant fertilizing agents.
- Study of symptoms and gene expression in four Pinus species after pine wood nematode infectionPublication . Franco, Albina R.; Santos, Carla; Roriz, Mariana; Rodrigues, Rui; Lima, Marta R. M.; Vasconcelos, Marta W.
- Study of the mineral composition of different Nigerian yam floursPublication . Piccirillo, Clara; Vincenza, Ferraro; Roriz, Mariana; Omohimi, Celstina; Abayomi, Louise A.; Vasconcelos, Marta W.; Sanni, Lateef; Pintado, ManuelaYam is a root crop essential for the lives of hundreds of millions of people in many African, Asian and South American countries. Yam roots are in fact used to produce a variety of food items, including yam flour. The flours are consumed mainly as a source of carbohydrate; however, they also supply several minerals which are essential for good state of health. In this study we report about a systematic investigation on the mineral composition of several Nigerian yam flours. More than 40 flours samples purchased from local market vendors and/or producers were analysed by ICP-OES spectrometry; the concentration of minerals (i.e. potassium, sodium, iron, etc.) was determined. Results showed variance in the mineral profile across different sources of the flour. This research also highlighted the nutritional potential of yam flours and allowed possible regional variations in the flour compositions to be monitored.
- Study of specific genes of infection by Bursaphalenchs xylophilus in Portuguese Pine treesPublication . Santos, Carla; Roriz, Mariana; Lima, Marta; Franco, Albina; Vasconcelos, Marta W.
- Conventional and novel approaches for managing “flavescence dorée” in grapevine: knowledge gaps and future prospectsPublication . Oliveira, M. J. R. A.; Roriz, M.; Vasconcelos, M. W.; Bertaccini, A.; Carvalho, S. M. P.“Flavescence dorée” (FD) is a grapevine quarantine disease associated with phytoplasmas and transmitted to healthy plants by insect vectors, mainly Scaphoideus titanus. Development of efficient methods for its control has been hampered by the lack of knowledge about phytoplasma biological properties, linked also to difficulties in its in vitro cultivation. Conventional management strategies rely mainly on the application of insecticide treatments, roguing of infected plants and production of phytoplasma‐free propagation material. However, these strategies are costly and could have undesirable environmental impacts. Novel approaches are being investigated using transcriptomic and proteomic tools that can assist in identifying key regulators expressed by diseased, recovered and healthy plants. These studies allowed the identification of molecular profiles linked to the grapevine cultivar‐diverse susceptibility that are of great interest for the development of FD less susceptible plants by breeding programmes. Other promising FD management strategies include the use of grapevine endophytic microorganisms with known biocontrol properties and endophytes living inside specialized insect cells, which can be potential candidates for FD vector control. Finally, the application of plant defence elicitors might be an interesting tool for FD containment, but more research is needed before it can be implemented. In this review, the methodologies used for detecting and confining FD diffusion are discussed, focusing mainly on conventional tools, current research perspectives and knowledge gaps.
- Study of symptoms and gene expression in four Pinus species after pinewood nematode infectionPublication . Franco, Albina R.; Santos, Carla; Roriz, Mariana; Rodrigues, Rui; Lima, Marta R. M.; Vasconcelos, Marta W.Pine wilt disease, caused by the pinewood nematode Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle, is originating severe infections in pine trees. The disease is detected when external symptoms appear (e.g. needle chlorosis), but trees could remain asymptomatic for long periods and serve as a long-term host. The primary goal of this study was to assess the effect of inoculation with an avirulent isolate of B. xylophilus (C14-5) on different Pinus spp. seedlings (P. sylvestris, P. nigra, P. pinea and P. pinaster). At the same time, seedlings were also inoculated with a virulent strain, HF, in order to compare the phenotypic and genomic results of the two types of inoculations. The effect of inoculation was determined in terms of expression of various Pinus genes potentially involved in the response to the disease.The results suggest that P. pinea and P. nigra are more resistant to infection by the nematode than P. sylvestris and P. pinaster. The phenotypic and genetic differences were more marked among P. pinea and P. pinaster.
- Effects of AtFRO2 expression in the nutritional enhancement of soybean (Glycine max. L)Publication . Santos, Carla; Roriz, Mariana; Lima, Marta; Vasconcelos, Marta W.
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