33 research outputs found

    Ecology, Biology, Damage, and Management of Sucking and Chewing Insect Pests of Citrus

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    Citrus are important commodities for human and animal nutrition but these crops are attacked by a plethora of dangerous agents, including viruses, bacteria, fungi, and invertebrates that decrease the yield significantly. Within invertebrates, insects are the more prevalent citrus pests causing plant damage or act as diseases vector. In this chapter, we focused in the insect pests with worldwide distribution in citrus orchards, including sap sucking Asian citrus psyllid Diaphorina citri, citrus mealybug Planococcus citri, citrus whitefly Dialeurodes citri, thrips representatives such as Scirtothrips citri and Pezothrips kellyanus, and chewing citrus leafminer Phyllocnistis citrella and lemon butterfly Papilio demoleus. These pests are distributed across various regions of different continents such as in Asia-pacific, Americas, Africa, and Oceana. We presented detailed data from these pests’ biology, ecology, damage, and methods for control. The pest incidence and biology is affected by various biotic and abiotic factors thus providing the opportunity to use these factors as method of intervention to disturb pest life cycle. In this context, several IPM techniques such as cultural, physical, biological, and chemical methods were elaborated, which could help to reduce the pest status below damaging levels

    Máscara facial artesanal pode ser esterilizada sem comprometer sua eficácia

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    Background and Objectives: COVID-19 caused by SARS-CoV-2 is transmitted by contact, droplets and aerosols. The World Health Organization recommends the mandatory use of surgical masks for health professionals and encourages countries to adhere to their use, en masse, in order to minimize the transmission of the virus. Since the lack of this personal protective equipment is a cause for concern, the objective of this study was to evaluate the characteristics of facial masks regarding (i) the mechanical properties of elongation, rupture stress and resistance to air passage and (ii) the morphometric properties of thickness, fiber diameter and pore distribution after autoclave sterilization. Methods: The masks were made in TNT Spunbonded (100% polypropylene, 60 g/m2), autoclaved at 70 ºC for 5 minutes and stored in plastic films at room temperature. Then, the mechanical properties were determined in an Instron universal testing machine and Gurley type automatic densimeter and the morphometric properties in a semi-automatic thickness gauge and scanning electron microscope. Results: It was observed that a cycle of sterilization of facial masks, by moist heat under pressure, increased the blanket's stiffness, did not produce physical damage and did not reduce the blanket's barrier capacity. Conclusion: The sterilization of face masks made of TNT can be considered a strategy to increase safety in their production and use.Antecedentes y objetivos: El COVID-19 causado por el SARS-CoV-2 se transmite por contacto, gotitas y aerosoles. La Organización Mundial de la Salud recomienda el uso obligatorio de mascarillas quirúrgicas para los profesionales de la salud y alienta a los países a adherirse a su uso, en masa, con el fin de minimizar la transmisión del virus. Dado que la falta de este equipo de protección personal es motivo de preocupación, el objetivo de este estudio fue evaluar las características de las máscaras faciales en cuanto a (i) las propiedades mecánicas de elongación, tensión de rotura y resistencia al paso del aire y (ii) la morfometría propiedades de espesor, diámetro de fibra y distribución de poros después de la esterilización en autoclave. Métodos: Las máscaras se fabricaron en TNT Spunbonded (100% polipropileno, 60 g / m2), se esterilizaron en autoclave a 70 ºC durante 5 minutos y se almacenaron en películas plásticas a temperatura ambiente. Posteriormente, se determinaron las propiedades mecánicas en una máquina de ensayo universal Instron y densímetro automático tipo Gurley y las propiedades morfométricas en un medidor de espesor semiautomático y microscópio electrónico escaneando.Resultados: Se observó que un ciclo de esterilización de mascarillas faciales, por calor húmedo a presión, incrementó la rigidez de la manta, no produjo daño físico y no redujo la capacidad barrera de la manta. Conclusión: La esterilización de mascarillas faciales fabricadas con TNT puede considerarse una estrategia para aumentar la seguridad en su producción y uso.Justificativa e Objetivos: A COVID-19 causada pelo SARS-CoV-2 é transmitida pelo contato, por gotículas e por aerossóis. A Organização Mundial da Saúde recomenda a obrigatoriedade do uso de máscaras cirúrgicas aos profissionais da saúde e incentiva os países a aderirem ao seu uso, em massa, a fim de minimizar a transmissibilidade do vírus. Posto que a falta desse equipamento de proteção individual causa preocupação, o objetivo deste trabalho foi avaliar as características de máscaras faciais quanto (i) às propriedades mecânicas alongamento, tensão de ruptura e resistência a passagem de ar e (ii) às propriedades morfométricas espessura, diâmetro das fibras e distribuição de poros após esterilização em autoclave. Métodos: As máscaras foram confeccionadas em TNT Spunbonded (100% polipropileno, 60 g/m2), autoclavadas a 70 ºC por 5 minutos e armazendadas em filmes plásticos a temperatura ambiente. Na sequência, as propriedades mecânicas foram determinadas em máquina de teste universal Instron e densímetro automático tipo Gurley e as propriedades morfométricas em medidor de espessura semiautomático e microscópio eletrônico de varredura. Resultados: Observou-se que um ciclo de esterilização das máscaras faciais, por calor úmido sob pressão, promoveu o aumento da rigidez da manta, não produziu danos físicos e não diminuiu a capacidade de barreira da manta. Conclusão: A esterilização de máscaras faciais confeccionadas em TNT pode ser considerada uma estratégia para aumentar a segurança na sua produção e uso

    Ultrastructure Of Midgut Endocrine Cells In Workers Of Stingless Bee

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    Volume: 81Start Page: 151End Page: 15

    A comparative study of digestive cells in different midgut regions of stingless bees (Hymenoptera: Apidae: Meliponinae)

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    Ultrastructure of the digestive cells was analyzed in three midgut regions (anterior, middle and posterior) of stingless bees. Variations occurs in the presence of lipid inclusions in the cells from posterior midgut and presence of double-membraned vesicles associated to microvilli in the anterior midgut. However, basal plasmic membrane infoldings and augmentation of surface area achieved by microvilli are very similar in all midgut regions. These results not supported the existence of fluid fluxes in the ectoperitrophic space and suggest that digestive cells in stingless bees are polifunctional, that is, there is not midgut region specialized in secretion or absorption as observed in other insects

    Trichospilus pupivorus (Hymenoptera: Eulophidae): first report of parasitism on Thagona tibialis (Lepidoptera: Lymantriidae) in Brazil

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    We report the occurrence of Trichospilus pupivorus Ferriere, 1930 (Hymenoptera: Eulophidae) parasitizing pupae of Thagona tibialis Walker, 1855 (Lepidoptera: Lymantriidae) collected on Terminalia catappa L. (Combretaceae) tree in Vicosa, Minas Gerais, Brazil. Fifty to 75 parasitoids emerged from three pupae of Th. tibialis. This is the first record of Tr. pupivorus for the American continent and a new host record.Relatamos a ocorrencia de Trichospilus pupivorus Ferriere, 1930 (Hymenoptera: Eulophidae) parasitando pupas de Thagona tibialis Walker, 1855 (Lepidoptera: Lymantriidae) coletadas em uma arvore de Terminalia catappa L. (Combretaceae) em Vicosa, Minas Gerais, Brasil. Cinquenta a 75 parasitoides emergiram de tres pupas de Th. tibialis. Este e o primeiro relato de Tr. pupivorus no continente americano como tambem um hospedeiro novo

    FMRFamide-like midgut endocrine cells during the metamorphosis in Melipona quadrifasciata anthidioides (Hymenoptera, Apidae)

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    The FMRFamide, gastrin and cholecystokinin (CCK) occurrence in endocrine cells of insects has been described by several authors, although their functions are still not well defined for this group of animals. In the present study, the occurrence of endocrine cells producing FMRFamide, gastrin 1 and CCK-8 in the midgut (ventriculus) of Melipona quadrifasciata anthidioides (Hymenoptera, Apidae), before, during and after the metamorphosis, were investigated by means of pre-embedding immunofluorescence techniques. FMRFamide reactivity was found in the endocrine cells as well as in the nervous fibers and neurons of the intestine of these bees. ‘Open’ and ‘closed’ types of FMRFamide-like cells were observed in last instar larvae. In the black eyed pupae the producing cells of FMRFamide seemed to be immature, and, in the workers, where the FMRFamide producing cells were more abundant, the production of this substance seemed to occur only in the open cells. Reactivity of the nervous fibers and neurons were observed, during the prepupae, white eyed pupae, and pink eyed pupae. The same did not occur with the midgut endocrine cells. There were no immunoreactivity observations for gastrin 1 and for CCK-8. The FMRFamide-like cells were present in the midgut of these insects during or close to the period that they were eating, which indicates that the FMRFamide may be involved in the control of the digestive process

    Special issue on recent advances in zoophytophagous arthropods for agroecosystems sustainability

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    Zoophytophagous predators (ZP) display an omnivorous behavior and feed on both plants and arthropods (Coll and Guershon 2002). On the one hand, zoophagy allows them to efectively feed on a wide range of prey, including many agricultural pests such as whitefies, moths, aphids, thrips, or mites. On the other hand, phytophagy allows them to remain and even establish in crops during periods of prey scarcity. These positive traits have led to the inclusion of many species of ZP in sustainable pest management programs for different crops worldwide (van Lenteren et al. 2018). In recent years, the use and conservation of ZP have been extensively promoted, mainly because ZP can sustain themselves on plant-provided materials even when prey is scarce in crop fields

    Occurrence of Atta laevigata (Hymenoptera: Formicidae) in the South of Espirito Santo State, Brazil. Recently Introduced or Endangered Species?

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    Ants of the genus Atta are the main pests of Brazilian agriculture, including annual crops, pasture and reforestation. Atta laevigata (F. Smith) (Hymenoptera: Formicidae) presents a wide distribution from the Northern Amazon Basin Region to Southern Brazil. However, this is the first report of its occurrence in the Espirito Santo State, Brazil where it was found in the Municipality of Castelo at 20 degrees 36'13 South Latitude, 41 degrees 11'05 West Longitude and an average altitude of 100 meters. The low number of nests of A. laevigata compared to those of Atta sexdens rubropilosa Forel may indicate that the first species has been recently introduced or is endangered in Espirito Santo State due to competition with other organisms or by the impact of anthropogenic factors.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Population Dynamics of Lepidoptera Pests in Eucalyptus urophylla Plantations in the Brazilian Amazonia

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    Forestry companies study the population dynamics of insect pests in Integrated Pest Management for cost effectiveness. The objective of this study was to obtain qualitative and quantitative information on population fluctuation of the Lepidopteran defoliators of Eucalyptus urophylla plants in the Brazilian Amazon rainforest. In all, 402 species were collected, of which 10 were primary pests, nine were secondary pests, and the remaining bore no definite relevance to eucalyptus. Primary pests formed a low percentage of the total species, although they recorded a high percentage of the total number of individuals. The abundance of secondary pests, except in Caracuru, was less than 150 specimens annually. Primary pests showed higher population peaks during periods of low precipitation. The small number of species and the high abundance of primary and secondary pests could be due to the availability of food, or a deficiency in natural biological control. This suggests the possibilities of population outbreaks in the eucalyptus plantations. The period of highest occurrence for insect species in these crops must be identified so that suitable strategies can be developed for Integrated Pest Management.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
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