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- Manual técnico: a cultura da PitaiaPublication . Trindade, Ana Rita; Trindade, Diamantino; Marques, Natália; Neto, Luís; Duarte, AmilcarO Algarve é uma região com grande tradição frutícola. A alfarrobeira e a laranja são as principais culturas, com mais de metade de toda a superfície ocupada com culturas permanentes. A implementação de novas culturas permite ampliar e diversificar a fruticultura da região, o que lhe adita valor e conduz a uma maior sustentabilidade da atividade agrícola.
- Poda de Citrinos na Região Mediterrânica. Manual TécnicoPublication . Barrote, Isabel; Neto, Luís; Guerrero, Carlos; Marques, Natália; Duarte, AmilcarA poda é uma prática comum em citrinos, mas que é por vezes questionada, por se tratar de uma operação dispendiosa e por as árvores não podadas terem produções razoáveis. No entanto, a poda tem provado ser de particular importância na citricultura mediterrânica, orientada para a produção de frutos para consumo em fresco. Nesta citricultura a poda permite aumentar a qualidade do fruto, a qual é altamente valorizada, pelo que a poda se torna necessária e é compensada pelo preço de venda dos frutos. A poda permite formar e controlar a copa da árvore para obter uma melhor produtividade e qualidade dos frutos e, simultaneamente, melhorar o estado sanitário da árvore e facilitar a execução de operações, como a colheita e os tratamentos fitossanitários. Neste manual, resumimos e explicamos as técnicas de poda utilizadas na citricultura mediterrânica e referimos os principais objetivos de cada tipo de poda, tendo em consideração a morfologia e a fisiologia dos citrinos. Este livro é o resultado de vários anos de trabalho em ensaios de poda realizados no Algarve e foi escrito no âmbito do Grupo Operacional “PodaCitrus - Otimização da poda em citrinos”, financiado por fundos da União Europeia, através do programa PDR2020. É, assim, o produto de um vasto trabalho de equipa, que, além dos autores, incluiu muitos agrónomos, responsáveis técnicos pelos pomares onde foram realizados os ensaios. Foi também importante a participação de agrónomos exteriores ao projeto, com quem discutimos os resultados obtidos e as técnicas de poda de citrinos praticadas nos campos. Os autores agradecem, em primeiro lugar, às empresas Frusoal, Citriaroeira, Produção Citrícola Lda, e João Santana Unipessoal, parceiras do projeto, mas também às empresas Quinta da Barragoa e Valenciagro (grupo Martinavarro) as respetivas colaborações. Pessoalmente, agradecemos a Silvino Oliveira, Angélica Mendonça, Valter Reis, Manuel Reis, Marta Afonso, Rui Antão, Tiago Guerreiro, Vera Sustelo, Luís Mendonça e Alfonso Barrau, toda a sua colaboração. Agradecemos também a Gonçalo Azinheira pela elaboração das ilustrações deste livro e a Miguel Santos pela edição de duas fotografias. Agradecemos ainda a Hugo Marques e a Vera Sustelo pela disponibilização de algumas fotografias.
- The antibacterial, anti-biofilm, anti-inflammatory and virulence inhibition properties of Portuguese honeysPublication . Silva, Carina Isabel da; S, Azza; Faleiro, Maria Leonor; Miguel, Maria; Neto, LuísIn Portugal, beekeeping activity has a significant weight among livestock production. The antimicrobial activities of Portuguese honeys have been reported, but the anti-biofilm formation and anti-virulence abilities have not been investigated. The main goal of this work was to study the impact of three monofloral honeys (citrus, lavender and strawberry tree) honeys on adherence of Staphylococcus aureus, methicillin-resistant S. aureus (MRSA) and Pseudomonas aeruginosa, as well as the influence of the same honeys on virulence using Galleria mellonella as a model. In addition, the general physico-chemical characterization of these honeys and the microbial quality were also performed. The anti-inflammatory activity was also estimated by analyzing the activity of the enzymes hyaluronidase and lipoxygenase. The tested honeys complied with European legislation and no microbial contamination was observed. Of all the honeys at 12.5 and 25%, w/v the citrus honey caused the highest inhibitory activity against P. aeruginosa. Strawberry tree honey at 25% w/v was able to significantly inhibit the MRSA strains. Anti-biofilm formation and anti-inflammatory activities were observed. The different honeys impaired the virulence of S. aureus and MRSA strains. The Portuguese honeys were capable of combating the tested bacterial pathogens not only by inhibiting their growth but also by affecting important pathogenicity properties, such as adherence and virulence.
- Feeding behavior of Liriomyza huidobrensis (Blanchard) and L. trifolii (Burgess) on bean leavesPublication . Ameixa, Olga; Almeida, Lynette; Gonçalves, Albertina; Neto, LuísThe adult feeding behavior of Liriomyza huidobrensis and L. trifolii was studied in beans of the variety “Catarino.” The insects were placed on a bean leaf and its behavior observed and recorded on DVD for a period of 30 min. An ethogram was constructed based on the different behavior parameters that were identified. The time that each species used in each behavior parameter was registered and compared between the two species. When placed in the arena the two species behaved in a similarmanner, although some differences were observed. The adaptation of the leafminers species to the “Catarino” bean variety under these experimental conditions and the possibility to use some behavioral parameters as indicators of the preference of these insects in relation to the host plant are discussed.
- Pitaya as a new alternative crop for Iberian Peninsula: Biology and edaphoclimatic requirementsPublication . Trindade, Ana Rita; Paiva, Paulo; Lacerda, Vander; Marques, Natália; Neto, Luís; Duarte, AmilcarPitaya is one of the fruit species whose demand has increased in recent years due to the numerous health benefits and lucrative price of the fruit and its by-products. In Europe, the Iberian Peninsula and other Mediterranean countries are the ones with favorable climatic conditions for its cultivation. This document describes much of the history of pitaya in the Iberian Peninsula and the difficulties related to its cultivation. A bibliographical survey was carried out on the culture of pitaya in the world, focusing on the edaphoclimatic requirements, and on the possibility of this becoming a consolidated crop in the Iberian Peninsula. The relatively low water requirement of pitaya makes this crop sustainable among crops that require irrigation. In addition, we provide a perspective for use and research of this emerging crop. There has been an exponential growth of scientific publi-cations on pitaya in the last decade; however, much more needs to be researched to know how to increase productivity as well as the sensory quality of fruits in different regions. This sustainable crop is a good option to diversify fruit production in the Iberian Peninsula.
- Moroccan propolis: a natural antioxidant, antibacterial, and antibiofilm against Staphylococcus aureus with no induction of resistance after continuous exposurePublication . EL-GEUNDOUZ, Soukaina; AAZZA, Smail; Lyoussi, Badiaa; Bankova, Vassya; Popova, Milena; Neto, Luís; Faleiro, Maria Leonor; Miguel, MariaThis study was performed to evaluate the total phenols, flavonoids, and antioxidant activities of twenty-four propolis samples from different regions of Morocco. In addition, two samples were screened regarding the antibacterial effect against four Staphylococcus aureus strains. Gas chromatography coupled to mass spectra (GC-MS) analysis was done for propolis samples used in antibacterial tests. The minimum inhibitory and minimum bactericidal concentration (MIC, MBC) were determined. The potential to acquire the resistance after sequential exposure of bacterial strains and the impact of adaptation to propolis on virulence using the Galleria mellonella were evaluated. Additionally, the effects of propolis extract on the bacterial adherence ability and its ability to inhibit the quorum sensing activity were also examined. Among the twenty-four extracts studied, the samples from Sefrou, Outat el Haj, and the two samples marketed in Morocco were the best for scavenging DPPH, ABTS, NO, peroxyl, and superoxide radicals as well as in scavenging of hydrogen peroxide. A strong correlation was found between the amounts of phenols, flavonoids, and antioxidant activities. Propolis extract at the MIC value (0.36 mg/mL) significantly reduced (p < 0.001) the virulence potential of S. aureus ATCC 6538 and the MRSA strains without leading to the development of resistance in the sequence of continuous exposure. It was able to impair the bacterial biofilm formation. The results have revealed that sample 1 reduces violacein production in a concentration dependent manner, indicating inhibition of quorum sensing. This extract has as main group of secondary metabolites flavonoids (31.9%), diterpenes (21.5%), and phenolic acid esters (16.5%).
- HLB e a psila-africana-dos citrinos: um novo problema e novas soluçõesPublication . Magalhães, Tomás; Duarte, Beatriz; Poeira, Rita; Neto, Luís; Marques, N T.; Duarte, AmilcarOs citrinos são uma cultura importante na Península Ibérica, fazendo parte da dieta mediterrânica e contribuindo para a economia dos dois países. Atualmente a citricultura desta região está ameaçada por uma doença devastadora, o huanglongbing, uma vez que a psila-africana-dos-citrinos, vetor da bactéria que causa esta doença, já se encontra em quase toda a região costeira de Portugal e também no norte de Espanha. A bactéria não foi até agora detetada, mas para travar o vetor, tem sido usada a luta biológica com um parasitóide da psila. A gravidade desta ameaça à nossa citricultura obriga a que se adotem novas abordagens de proteção fitossanitária, incluindo estratégias coletivas, abrangendo várias explorações agrícolas.
- Report of in vitro antileishmanial properties of Iberian macroalgaePublication . Bruno De Sousa, Carolina; Lago, João Henrique G.; Macridachis, Jorge; Oliveira, Marta; Brito, Luis; Vizetto-Duarte, C; Florindo, Claudia; Hendrickx, Sarah; Maes, Louis; Morais, Thiago; Uemi, Miriam; Neto, Luís; Dionísio, Lídia; Cortes, Sofia; Barreira, Luísa; Custódio, Luísa; Alberício, Fernando; Campino, Lenea; Varela, JoãoHere is reported the anti Leishmania infantum activity of 48 hexane, CH2Cl2 and MeOH extracts from 16 macroalgae collected on the Iberian Coast. Seven hexane and CH2Cl2Cystoseira baccata, Cystoseira barbata, Cystoseira tamariscifolia, Cystoseira usneoides, Dictyota spiralis and Plocamium cartilagineum extracts were active towards promastigotes (IC50 29.8-101.8 μg/mL) inducing strong morphological alterations in the parasites. Hexane extracts of C. baccata and C. barbata were also active against intracellular amastigotes (IC50 5.1 and 6.8 μg/mL, respectively). Fatty acids, triacylglycerols, carotenoids, steroids and meroterpenoids were detected by nuclear magnetic resonance (NMR), and gas chromatography in the Cystoseira extracts. These results suggest that Cystoseira macroalgae contain compounds with antileishmanial activity, which could be explored as scaffolds to the development of novel sources of antiparasitic derivatives.
- Current distribution of the African citrus psyllid Trioza erytreae in Portugal: relation to climatic conditionsPublication . Duarte, Beatriz; Poeira, Rita; Magalhães, Tomás; Paiva, Paulo; Soares, Celestino; Neto, Luís; Marques, Natália; Duarte, AmilcarThe onset of Trioza erytreae, the African citrus psyllid, in the northwest of the Iberian Peninsula (north of Portugal and northwest of Spain) caused great concern among citrus growers in Europe. This insect is a vector of the bacteria Candidatus Liberibacter spp., the causal agent of huanglongbing, one of the most devastating citrus diseases. The first report of T. erytreae presence in mainland Europe refers to an area with isolated citrus trees and no significant citrus orchards. However, it was predictable that T. erytreae could spread quickly reaching the most important citrus growing area, in the south. Therefore, the Portuguese citrus industry is the first to be threatened in Europe, but the entire European citrus industry is at risk. In addition to the containment measures taken by the Portuguese and Spanish Phytosanitary Services, several models were made to predict how the African citrus psyllid could advance through the territory of the two countries. Releases of the parasitoid Tamarixia dryi were used for psyllid control. Despite that, T. erytreae has moved south and is on the verge of reaching the most important Portuguese citrus-producing area, which is connected to the citrus-growing areas of the other Mediterranean countries. This advance took place along the coast, without reaching interior regions of the country, where, according to some models, a high-water vapor pressure deficit hinders the insect's development in warmer areas. Populations of T. erytreae dropped significantly in 2021 and 2022, making it difficult to detect even in previously infested areas. This doesn't give farmers peace of mind because the presence of T. erytreae, even in low populations, could lead to a quick spread of huanglongbing, if or when the disease arrives in Europe. Therefore, it is crucial to continue to monitor T. erytreae populations and implement the necessary containment measures for the vector.