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- Efeito de dois alimentos artificiais na longevidade e fecundidade dos adultos de traça da oliveira, Prays oleae (Bern.).Publication . Jorge, S.; Cabanas, J.E.; Pereira, J.A.; Bento, Albino; Torres, L.
- Data on the natural control of the olive moth, Prays oleae, by parasitoids in Trás-os-Montes region (Northeastern - Portugal).Publication . Bento, Albino; Torres, L.; Pereira, J.A.
- Effects of gamma irradiation on sugars, fatty acids and tocopherols of chestnuts (Castanea sativa Miller)Publication . Barros, Lillian; Antonio, Amilcar L.; Barreira, João C.M.; Fernandes, Ângela; Bento, Albino; Botelho, M. Luísa; Ferreira, Isabel C.F.R.As seasonal products chestnuts have to be postharvest treated to increase their shelf-life. The most common preservation method for chestnuts is the use of chemical fumigation with methyl bromide, a toxic agent that is under strictly use under Montreal Protocol due to its adverse effects on human health and environment. Food irradiation is a possible feasible alternative to substitute the traditional quarantine chemical fumigation treatment. The main studies in chestnuts irradiation were done in an Asian variety, which is bigger and sweeter than the European types. However, on Portuguese varieties nothing has been reported. Herein, the influence of irradiation and storage time in sugars, fatty acids and tocopherols profiles/quantities in chestnuts obtained in Trás-os-Montes, Northeast Portugal, was evaluated for the fist time.
- Sistemas de condução e podaPublication . Bento, Albino; Rodrigues, M.A.; Pereira, J.A.Quando as árvores se desenvolvem livremente, sem qualquer intervenção humana, adotam a estrutura e o porte caraterístico da espécie e/ou da variedade a que a planta pertence. O porte dependerá ainda de características do meio em que se desenvolve, como as condições climáticas e a fertilidade geral do solo. Crescendo livremente, a estrutura natural da amendoeira torna-se desadequada ao cultivo, dificultando práticas culturais como a colheita, a proteção sanitária e genericamente a passagem de tratares e alfaias. De uma maneira geral, pode agravar-se a incidência de pragas e doenças, pela redução da luminosidade e arejamento no interior da copa e haverá tendência para se reduzirem as produções. Na amendoeira, a poda é vista como uma das técnicas culturais mais determinantes na rendibilidade da cultura, não apenas pêlos encargos com a operação, mas também pêlos efeitos que pode ter. na produtividade, na longevidade das arvores e na qualidade dos frutos (Arquero et al., 2007; 2013).
- Can Beauveria bassiana (Bals.-Criv.) Vuill. control the key fruit pests of the european chestnut tree, under field conditions?Publication . Souza, Maria Eliza Cota e; Nobrega, Filomena; Bento, Albino; Souza, Maria Eliza Cota eSimple Summary Portugal has the largest chestnut tree plantation area for fruit production in Europe. The carpophagous pests Cydia splendana Hubner and Curculio elephas Gyllenhal are among the main pests that affect nut productivity and quality in the country. Their control is considered difficult due to the large size of the trees, and chestnut orchards are mostly located in mountain regions with high slopes. On the other hand, the biology of the insects, which spend most of their life cycle inside the fruit or buried in the ground, is an aspect that makes them difficult to control. Entomopathogenic fungi are considered safe biological organisms for the environment and capable of regulating the natural population of pests. Beauveria bassiana (Bals.-Criv.) Vuill. is one of the most used for this purpose; however, its effectiveness is highly influenced by environmental factors. The study aimed to investigate the efficiency of B. bassiana in controlling these two carpophagous pests under environmental conditions. The fungus could infect and kill C. splendana and C. elephas larvae under the two conidial concentrations tested, showing favorable results for its use in the biocontrol of these insects. The chestnut moth (Cydia splendana Hubner) and the chestnut weevil (Curculio elephas Gyllenhal) cause serious damage to European producers and companies that transform and market the chestnut. The objective of the present work was to evaluate, under field conditions, the possibilities of Beauveria bassiana (Bals.-Criv.) Vuill. to infect and kill the larvae of the two main carpophagous pests of European chestnut, in treatments directed at the soil. For this purpose, the surfaces of vases were sprayed with two concentrations of conidia/mL 5 x 10(7) (T1) and 1 x 10(8) (T2). The control (T0) was sprayed with distilled water. Larval mortality and infection were evaluated on five dates (D8 to D220). Confirmation of the fungus present in the larva was performed by molecular analysis. The results obtained are promising for the use of B. bassiana as a biological control agent against these key pests of the chestnut crop. There were no significant differences in mortality between the T1 and T2 modalities, however, they were significantly higher than the control. In the case of total mortality (dead and infected larvae), no significant differences were observed for C. elephas either. In the case of C. splendana, the T2 modality obtained better results in terms of total mortality.
- Efeito do coberto vegetal na biodiversidade funcional de artrópodes associados a castanheirosPublication . Souza, Maria Eliza Cota e; Bento, Albino; Souza, Maria Eliza Cota eO castanheiro apresenta grande importância económica e social, sendo em algumas regiões de montanha a principal fonte de rendimento das populações rurais, constituindo-se ainda como elemento caraterizador da paisagem. Tem como pragas-chave a vespa-das-galhas-docastanheiro, Dryocosmus kuriphilus (Yasumatsu), bichado-da-castanha, Cydia splendana (Hübener) e o gorgulho, Curculio elephas (Gyllenhal). A vegetação espontânea do souto pode fornecer alimento, hospedeiros alternativos e abrigo para os inimigos naturais e incrementar a limitação natural destas pragas. O conhecimento da artropodofauna (fitófagos, predadores, parasitóides e indiferentes) e a sua atividade funcional é fundamental numa perspetiva de conservação e incremento da sustentabilidade. Neste contexto, este trabalho teve por objetivo avaliar o efeito do coberto vegetal nos índices de biodiversidade, bem como na riqueza e abundância da fauna auxiliar associada à cultura do castanheiro na região de Trás-os-Montes. O trabalho foi desenvolvido em dois soutos no distrito de Bragança, um com coberto vegetal e outro mobilizado, onde se procedeu à recolha quinzenal de artrópodes entre agosto e outubro de 2020, através da técnica das pancadas (25 árvores, dois ramos/árvore, duas abanadelas/ramo). Os indivíduos foram triados em laboratório e separados por ordens e grupos funcionais (predadores, parasitóides, fitófagos e indiferentes), os dados analisados no programa Past 4.3. No total, capturaram-se 5.020 artrópodes pertencentes à classe Insecta (nove ordens) e à classe Arachnida (uma ordem). Em termos de biodiversidade, o souto com coberto vegetal apresentou maior abundância (p<0,01) e menor dominância (p<0,001) que o souto mobilizado. Analisando os grupos tróficos observou-se que o souto com coberto vegetal apresentou maior número de parasitóides (p<0,05) e menor número de fitófagos (P<0,01), com destaque para a família Cicadellidae. Não houve diferença significativa no número de predadores. A ordem Araneae representa aproximadamente 80% dos predadores
- Resposta da couve Tronchuda (Brassica oleracea var costata) à aplicação de azoto, boro e um fertilizante orgânico para agricultura biológicaPublication . Rodrigues, M.A.; Pereira, J.A.; Arrobas, Margarida; Andrade, Paula B.; Bento, Albino
- Antioxidant activity of methanolic extracts from Cydonia oblong leavesPublication . Bento, Albino; Pereira, J.A.The olive moth, Prays oleae (Bernard) (Lepidoptera: Yponomeutidae), is one of the most destructive pests of olive groves in the Mediterranean basin. In recent years, the interest in evaluating the economic importance of P. oleae has been increasing, being loss assessment essential to the development of integrated pest management programs (IPM). Reliable economic thresholds for the pest are associated to any IPM practice, since enables the growers to reduce the input of pesticides and even target their use, when necessary. The purpose of this study was to establish economic thresholds against the fruit generation of P. oleae (Bern.) in Trás-os-Montes region (north-eastern Portugal), where the olive moth is a key pest of olive (Bento et al., 1997; Bento, 1999). The study was carried out in olives of the oil-producing variety "Cobrançosa, Verdial Transmontana and Madural", grown on non irrigated conditions and without pesticide treatments for several years. Data of Cobrançosa variety were recorded every year from 1993 to 2006. Olive infestation was determined in 25 fruits taken from 25 trees selected at random in orchard, weekly collected, from the time of fruit setting until the end of the egg-laying period. Crop losses due to preharvest fruit drop were evaluated on 25 olive trees from fruit setting until harvest. A mathematical model is developed which aims to establish the economic thresholds for the olive moth in Portugal. The model takes into account several factors such as: cost and efficacy of spraying, environmental impact, expected yield, price and crop losses.
- Biologia da cochonilha negra da oliveira, Saissetia oleae (Oliv.) no Nordeste de Portugal.Publication . Pereira, J.A.; Bento, Albino; Torres, L.
- Contribuição para o conhecimento da bioecologia do algodão da oliveira, Euphyllura olivina Costa, na região de Trás-os-Montes (Nordeste de Portugal).Publication . Pereira, J.A.; Lousão, C.; Bento, Albino; Cabanas, J.E.; Torres, L.