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- Diversidade e abundância de Sirfídeos (Diptera: Syrphidae) em pomares de limoeiros, amendoeiras e vinhas no Norte de PortugalPublication . Madureira, Marta; Rodrigues, Isabel; Pereira, J.A.Os sirfídeos (Diptera: Syrphidae) são insetos holometabólicos que no estado adulto são polinizadores, alimentando-se de néctar e pólen, mas no estado larvar há espécies que atuam como predadores vorazes de algumas pragas agrícolas, e outras têm uma função saprófaga. Por tal, os sirfídeos são importantes nos ecossistemas agrários pela sua ação como agentes de proteção biológica, polinizadores e indicadores da qualidade do ecossistema. Neste sentido, o conhecimento da sua abundância e diversidade nos ecossistemas agrários é de grande importância. No presente trabalho estudou-se a diversidade e a abundância de sirfídeos (Diptera: Syrphidae) em pomares de limoeiros, amendoeiras e vinhas localizados na região Norte de Portugal. As amostragens foram realizadas em 2018, em julho, agosto e outubro, no coberto vegetal e na copa das árvores com recurso a uma rede entomológica. O material recolhido foi levado para o laboratório onde se procedeu a separação e identificação até ao mais baixo nível taxonómico possível. No total foram recolhidos 186 indivíduos adultos que pertencem a cinco espécies diferentes, nomeadamente Eupeodes corollae (Fabricius, 1794), Melanostoma mellinum (Linnaeus, 1758), Paragus quadrifasciatus (Meigen, 1822), Sphaerophoria rueppelli (Wiedemann, 1830) e Sphaerophoria scripta (Linnaeus, 1758). Sphaerophoria scripta foi a espécie mais abundante em todos os agroecossistemas amostrados, representando mais de 54% dos indivíduos amostrados. A maior abundância de sirfídeos foi registada nas vinhas (110), seguindose os amendoais (49) e por fim os pomares de limoeiros (17). A maior abundância e diversidade de sirfídeos foi observada no mês de julho no coberto vegetal, com exceção das vinhas, onde a maior abundância e diversidade se registou nesse período na copa da videira. O baixo número e diversidade de sirfídeos recolhidos poderá estar relacionado com a época em que ocorreram as amostragens pelo que esse período será alargado em futuros trabalhos.
- Spatial distribution pattern of male adults of Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) in lemon orchards in Northern PortugalPublication . Costa, Jaciley Bragança; Madureira, Marta; Pereira, J.A.; Rodrigues, IsabelPhyllocnistis citrella Stainton, commonly known as the citrus leafminer, threatens global citrus production. This study focuses on elucidating the population dynamics and spatial distribution of P. citrella in lemon orchards located in Northern Portugal. From May to December, using delta traps with sexual pheromones, the levels of the adult population were monitored, and aggregation indices were calculated. Five distinct density peaks are observed, with the highest recorded in late July to early August. Spatial distribution consistently indicated an aggregated pattern. However, temporal variation in distribution was observed on specific dates. According to our results, it is suggested deploying two or three traps per hectare during peak density periods. This study significantly advances our understanding of P. citrella dynamics, emphasizing the need to consider spatial and temporal patterns for effective pest management. The outcomes underscore the importance of further exploration into factors influencing distribution patterns to refine control strategies. These insights are crucial for devising targeted and efficient measures to mitigate the impact of P. citrella on citrus orchards globally.
- Evolução das caraterísticas físico-químicas e sensoriais de azeites aromatizados com manjericão e orégãosPublication . Bobiano, Marta; Madureira, Marta; Rodrigues, Nuno; Peres, António M.; Pereira, J.A.A aromatização de azeites é uma prática ancestral e usual ao nível doméstico. Nas últimas décadas tem aumentado no mercado a disponibilização de azeites aromatizados com diferentes condimentos e temperos, muitas vezes como forma de valorização de azeites que não eram exuberantes do ponto de vista sensorial.
- Community of Syrphids (Diptera: Syrphidae) in mediterranean perennial cropsPublication . Madureira, Marta; Pereira, J.A.; Rodrigues, IsabelSyrphids are holometabolic insects that provide several ecosystem services. In Mediterranean perennial crops, these insects play a fundamental role in the biological control of pests, in the pollination of agricultural crops and adjacent vegetation , and in the decomposition of organic matter, while the inter-rows provide shelter for other natural enemies, thus favouring predation and parasitism of crop pests. However, the ecosystem services provided by these insects or other arthropods have been compromised due to the simplification of the landscape, reduction of seminatural habitats, and increase in urbanization and agriculture. Therefore, understanding how the surrounding landscape of the crops and ground cover vegetation composition affects the syrphids is essential to implementing strategies to promote the presence of the Syrphids in the Mediterranean perennial crops and busting its ecosystem services. For that, this work was divided into two parts. In the first (Chapter 3), the Syrphidae community in Portuguese vineyards was described, and the response of the most abundant species, Sphaerophoria scripta Linnaeus, 1758, and Melanostoma mellinum Linnaeus, 1758, to the landscape composition and configuration within a gradient of distances (500, 1000, and 2000 m) from the sampled vineyards was studied. And in the second (Chapter 4), the flowering plants present in olive groves' vegetation cover were described, and these plant families' effect on the abundance of S. scripta was studied. Our results in vineyards showed that the presence of seminatural habitats and other crops in the surrounding landscape increased the abundance of S. scripta and M. mellinum, at the largest distance. In contrast, the artificial territory, olive orchards, and vineyards reduced M. mellinum at some of the buffers. In olive groves, 90 plant species belonging to 20 families were identified in the ground cover vegetation of olive groves. Asteraceae was the dominant flowering family, followed by Poaceae. The flowering plants of the families Campanulaceae, Asteraceae, Orobanchaceae, and Plantaginaceae in the ground cover vegetation promoted the abundance of S. scripta in the olive grove. On the other hand, flowering plants of the families Poaceae and Polygonaceae negatively affect the abundance of this syrphid. Increasing seminatural habitats in the surrounding landscape and the percentage of plant families more attractive in the adjacent vegetation and/or inter-rows in the Mediterranean perennial crops may favour syrphid abundance.
- O uso de óleos essenciais na aromatização de azeites da cv. ArbequinaPublication . Bobiano, Marta; Madureira, Marta; Rodrigues, Nuno; Peres, António M.; Pereira, J.A.As características dos azeites vão evoluindo após extração, e no caso dos azeites da cv. Arbequina existem relatos que referem ter um tempo de prateleira curto em comparação com azeites extraídos de outros cultivares como as tradicionais portuguesas.
- Caraterização morfológica e físico-química de diferentes cultivares de cereja produzidas em ResendePublication . Rodrigues, Nuno; Moura, Carina Manuela Machado de; Madureira, Marta; Rodrigues, Isabel; Martins, Vanessa Fernandes; Ramos, Ana Cristina; Ferreira, Armando; Sousa, Beatriz Andreia de Lima; Pereira, J.A.A região de Resende é uma região tradicional de produção de cereja que nos últimos anos tem apostado em novas plantações e no desenvolvimento da cultura. São várias as cultivares de cereja possíveis de encontrar. Neste sentido, com o presente trabalho pretendeu-se proceder à caraterização morfológica e físico-química de frutos de cinco cultivares, tendo sido recolhidas 29 amostras de cerca de 1 kg de cereja, de diferentes produtores e de diferentes cultivares, nomeadamente: Van (9 amostras), Durona (7 amostras), Lapin (7 amostras), Summit (4 amostras) e Sunburst (2 amostras). De cada amostra foram retirados aleatoriamente 20 frutos e em cada fruto foi avaliada ao nível morfológico a massa do fruto (com e sem pedúnculo) (g), comprimento do fruto (mm), diâmetro máximo do fruto (mm); diâmetro mínimo do fruto (mm), massa do caroço (g) e relação polpa caroço. Em termos físico-químicos avaliou-se a firmeza, cor, teor de sólidos solúveis totais e acidez titulável. Os resultados indicam a existência de diferenças assinaláveis entre as cultivares em estudo. Assim, a Summit foi a cultivar que apresentou frutos mais compridos (20,52 mm ± 0,99 mm), maior diâmetro 24,94 mm ± 1,34 mm, e a variedade onde se registaram os frutos mais pesados (7,24 g ± 1,09 g). De uma maneira geral o teor em sólidos solúveis totais oscilou entre 12,79% e 16,91%, sendo os valores mais elevados registados na Summit e os valores inferiores na Durona. Ao nível da acidez, firmeza e cor também se registaram diferenças entre cultivares.
- Ground-cover vegetation composition shapes the abundance of Sphaerophoria scripta (Diptera: Syrphidae) in Mediterranean olive grovesPublication . Madureira, Marta; Rodrigues, Isabel; Pereira, J.A.The ground-cover vegetation, commonly found in olive groves, provides shelter and vital floral resources for syrphids. Such resources can contribute to syrphids’ growth, development, reproduction, and survival, allowing them to maximize their function as natural pest enemies, pollinators, and decomposers of organic matter. Therefore, identifying the flowering plant families driving the abundance of Sphaerophoria scripta Linnaeus, 1758, is essential to promote its presence and abundance. Here, we described the flowering plants present in the vegetation cover of olive groves and studied how these flowering plant families shape the abundance of S. scripta. A total of 90 plant species belonging to 20 families were identified. Asteraceae was the dominant flowering family, followed by Poaceae. The generalized linear model showed that the presence of flowering plants of the families Campanulaceae, Asteraceae, Orobanchaceae, and Plantaginaceae in the ground-cover vegetation promotes the abundance of S. scripta in olive groves. Conversely, flowering plants of the families Poaceae and Polygonaceae were associated with the decreased abundance of this syrphid species. Our results suggest that increasing particular plant families and decreasing others in the ground-cover vegetation may favor S. scripta abundance in the Mediterranean olive groves.
- The surrounding landscape shapes the abundance of Sphaerophoria scripta and Melanostoma mellinum (Diptera: Syrphidae) in Portuguese vineyardsPublication . Madureira, Marta; Rodrigues, Isabel; Villa, Maria; Pereira, J.A.1. The intensification of urban and agricultural use in the landscape is the major driver of biodiversity loss and the consequent decrease of ecosystem services provided by insects. Syrphids are important ecosystem service providers, including pest regulation, pollination, and matter decomposition. 2. Understanding how the surrounding landscape to crops affects syrphids is essential to implementing strategies to reverse the negative effects of the agricultural landscape’s simplification. 3. This study describes the Syrphidae community in Portuguese vineyards and the response of the most abundant species, Sphaerophoria scripta Linnaeus, 1758, and Melanostoma mellinum Linnaeus, 1758, to the landscape composition and configuration within a gradient of distances (500, 1000, and 2000 m) from the sampled vineyards. 4. The presence of seminatural habitats and other crops in the surrounding landscape increased both species at the largest distance, whereas the presence of artificial territory, olive orchards, and vineyards reduce M. mellinum at some of the buffers. 5. Increasing seminatural habitats in the vineyards surrounding landscape (2000 m) and, potentially, introducing nature-friendly practices in the principal crops around vineyards may favour syrphid abundance.
- Unmasking Sensory Defects of Olive Oils Flavored with Basil and Oregano Using an Electronic Tongue-Chemometric ToolPublication . Bobiano, Marta; Rodrigues, Nuno; Madureira, Marta; Dias, L.G.; Veloso, Ana C.A.; Pereira, J.A.; Peres, António M.Olive oil price and consumers’ preference depend on the commercial grade classification that can decrease if any sensory defect is perceived leading to an economic loss. Enriched oils, obtained by incorporating dried aromatic herbs, spices, or essential oils, which is a common practice in the Mediterranean region, are commercially available. This practice may conceal the fraudulent purpose of masking the perception of sensory defects. The detection of this type of fraud is a difficult task, requiring sensory analysis. Thus, in this study, extra-virgin and lampante olive oils, the latter classification being due to the perception of an intense winey-vinegary defect, were deliberately enriched with different amounts of basil-dried herbs and oregano-dried herbs. Sensory analysis showed that, depending on the aromatic herb and on the added amount (0.011–0.110 g herb per kg oil), the defect intensity could be masked leading to an erroneous classification of flavored lampante oils as flavored virgin oils. In contrast, the electronic tongue-chemometric approach could unmask the defect in flavored oils (predictive sensitivities: 70–78%) and semiquantitatively discriminate flavored oils according to the added levels of basil or oregano (predictive sensitivities: 93–100%). The electronic tongue approach showed satisfactory unmasking performance when compared with the sensory panel, and so, its future application as a quality control tastesensor device for disclosing olive oil sensory defects masked by the incorporation of flavoring agents may be forseen.
- O uso de óleos essenciais na aromatização de azeites da cv. ArbequinaPublication . Bobiano, Marta; Madureira, Marta; Rodrigues, Nuno; Peres, António M.; Pereira, J.A.As características dos azeites vão evoluindo após extração, e no caso dos azeites da cv. Arbequina existem relatos que referem ter um tempo de prateleira curto em comparação com azeites extraidos de outros cultivares como os tradicionais portugueses.