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Since the early 1990s, and almost simultaneously, unknown diseases started to be observed in many crops, especially in tropical and subtropical regions. These diseases were predominantly caused by begomoviruses, which were poorly known at that time. Their vector, the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae), often reached unprecedented huge populations in agricultural areas. This elicited a serious production crisis worldwide, that caused losses of millions of dollars for farmers in many countries, including the Mesoamerican region. Fortunately, in Costa Rica, some local research centers, with the collaboration of foreign specialists, have been able to study the causes of this phenomenon, in the search for solutions based on solid epidemiological information. In addition to the previously reported native Bemisia tabaci species, New World (NW), two exotic species, -Mediterranean (MED) and Middle East-Asia Minor 1 (MEAM1)- were found. Moreover, native and exotic bipartite begomoviruses have been detected, especially in common bean, cucurbits, tomato and sweet pepper, as well as the worldwide spread monopartite begomovirus Tomato yellow leaf curl virus (TYLCV). Based upon biological and ecological knowledge accumulated to date, this review offers a comprehensive overview of the very dynamic ways in which the interactions of the different whiteflies and begomovirus species have expressed in Costa Rica, with emphasis on vegetable pathosystems. Hopefully, the information provided in this paper may allow farmers, extension agents, and researchers involved in vegetable production to develop sound practical responses to current and unforeseen problems regarding whiteflies and their associated viruses.

Desde inicios del decenio de 1990 y de manera casi simultánea, se empezaron a observar afecciones desconocidas en numerosos cultivos, sobre todo en regiones tropicales y subtropicales. Dichas enfermedades eran causadas por begomovirus hasta entonces poco estudiados. Su vector es la mosca blanca Bemisia tabaci (Hemiptera: Aleyrodidae), de la que no se habían registrado poblaciones tan desmedidas en áreas agrícolas. Ello originó una seria crisis de producción a nivel mundial, con pérdidas millonarias para los agricultores de numerosos países, incluyendo la región de Mesoamérica. Por fortuna, en Costa Rica, algunos centros de investigación, con la colaboración de especialistas extranjeros, han podido profundizar en las causas de este fenómeno, para buscar soluciones fundamentadas en información de carácter epidemiológico. Además de la especie de B. tabaci New World (NW), nativa y previamente conocida, en años recientes han ingresado sendas especies del Mediterráneo (MED) y el Medio Oriente-Asia Menor 1 (MEAM1). Asimismo, se ha detectado la presencia de begomovirus bipartitas, nativos y exóticos, especialmente en frijol común, cucurbitáceas, tomate y chile; además, se detectó el begomovirus monopartito conocido a nivel mundial Tomato yellow leaf curl virus (TYLCV) en tomate. Con base en el conocimiento biológico y ecológico acumulado hasta ahora, en la presente revisión se aporta una panorámica del dinamismo con que se han expresado en Costa Rica las interacciones entre las diferentes especies vectoras y los distintos begomovirus, con énfasis en patosistemas de hortalizas. Se espera que la información aquí presentada permita mejorar el tipo de respuestas prácticas y eficaces de parte de agricultores, extensionistas agrícolas e investigadores involucrados en la producción de hortalizas, frente a problemas actuales o imprevistos.

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Resumen Hypsipyla grandellaes una plaga forestal clave en América Latina y el Caribe, donde ha impedido todo intento de establecer plantaciones comerciales de caobas (Swieteniaspp.) y cedros (Cedrelaspp.). En la búsqueda de métodos de manejo de sus larvas, que sean preventivos y rentables, así como basados en recursos de la flora tropical, fue evaluada la actividad fagodisuasiva del extracto crudo y de cuatro particiones fitoquímicas (agua, hexano, diclorometano y acetato de etilo) de la flor de reina de la noche,Brugmansia candida(Solanaceae). Se efectuaron bioensayos de laboratorio con concentraciones crecientes del extracto crudo (0.1; 0.3; 1.0; 3.2 y 10.0 % m/v) y con cada una de las particiones (según el rendimiento del proceso de particionamiento). Se utilizó un diseño de bloques completos al azar, con cuatro repeticiones, y se expusieron larvas de instar III de H. grandellaa discos de cedro amargo (Cedrela odorata) impregnados con el respectivo tratamiento, por 24 h. Se midió el porcentaje de consumo de cada disco. El extracto crudo y la partición de hexano, mostraron un evidente efecto fagodisuasivo a partir de concentraciones de 1.0 % y 0.122 % m/v, respectivamente. También se realizó un bioensayo para comparar una sola concentración (0.38 % m/v) del alcaloide escopolamina, el cual redujo en 90% el consumo con respecto a los testigos. Asimismo, se evaluó la mortalidad y los efectos subletales en larvas expuestas al extracto crudo, la partición de hexano y la escopolamina, pero no hubo evidencias de ellos, lo que confirmó su acción fagodisuasiva. Además, se realizó un tamizaje fitoquímico del extracto crudo, y mediante pruebas cualitativas se determinó que los alcaloides, taninos, triterpenos y cumarinas fueron los metabolitos secundarios más importantes. Finalmente, se confirmó la presencia de la escopolamina tanto en el extracto crudo como en la partición de hexano, mediante el método de cromatografía de gases acoplado a un espectrómetro de masas (GC-MS). Se recomienda preparar una formulación de escopolamina más algunos coadyuvantes, y evaluar su eficacia en condiciones de invernadero, como un primer paso para avanzar en el desarrollo de un fagodisuasivo comercial.

Abstract Hypsipyla grandella is a key forest pest in Latin America and the Caribbean, where it has precluded attempts to establish commercial plantations of mahoganies (Swieteniaspp.) and cedars (Cedrelaspp.). In the search for methods to manage its larvae, being both preventative and cost-effective, as well as based upon resources from tropical flora, the crude flower extract of angel's trumpet, Brugmansia candida, as well as four partitions thereof (water, hexane, dichlorometane, and ethyl acetate), were tested for phagodeterrence. Laboratory bioassays involved increasing concentrations of the crude extract (0.1, 0.3, 1.0, 3.2 and 10.0 % w/v) as well as each one of the partitions (in accordance to the yield obtained from the partitioning process). A randomized complete block design, with four replicates, was used. H. grandellainstar III larvae were exposed for 24 h to Spanish cedar (Cedrela odorata) leaf discs dipped into the respective treatment, after which disc consumption was measured. Strong phagodeterrence was detected at concentrations as low as 1.0 % y 0.122 % w/v for the crude extract and the hexane partitions, respectively. In addition, a single bioassay was performed to compare a single concentration (0.38 % w/v) of the alkaloid scopolamine, which reduced consumption in 90 % with respect to the controls. Also, mortality and sublethal effects were assessed in larvae exposed to the crude extract, the hexane partition and scopolamine, with no evidence for them, which confirmed their phagodeterrence. Moreover, the crude extract was submitted to a phytochemical screening by means of a number of qualitative tests, which showed that alkaloids, tannins, triterpenes and cumarins were the most important secondary metabolites. Finally, the presence of scopolamine was confirmed in both the crude extract and the hexane partition, by means of the gas chromatography-spectrometry (GC-MS) analytical method. It is recommended to prepare a formulation of scopolamine plus some adjuvants, in order to test its effectiveness under greenhouse conditions, as a first step to advance in the development of a commercial phagodeterrent. Rev. Biol. Trop. 66(1): 58-69. Epub 2018 March 01.

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A glossary is presented, despite being a non-exhaustive one, which includes a little more than one hundred terms frequently misused in entomological publications. They are organized in accordance to their degree of acceptance by the Real Academia Española. Each one is accompanied by its correct alternative (sometimes with a brief justification of the suggested term), and its proper use is illustrated with an example. Moreover, in addition to idiomatic mistakes themselves, a brief list of rather common conceptual mistakes is included, which correct use is explained.

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On some misused terms in entomological publications. A glossary is presented, despite being a non-exhaustive one, which includes a little more than one hundred terms frequently misused in entomological publications. They are organized in accordance to their degree of acceptance by the Real Academia Española. Each one is accompanied by its correct alternative (sometimes with a brief justification of the suggested term), and its proper use is illustrated with an example. Moreover, in addition to idiomatic mistakes themselves, a brief list of rather common conceptual mistakes is included, which correct use is explained. Rev. Biol. Trop. 59 (3): 999-1006. Epub 2011 September 01.

Este artículo consiste en un glosario, aunque no exhaustivo, de un poco más de cien términos con cierta frecuencia empleados de manera incorrecta en publicaciones entomológicas. éstos se clasifican según el grado de aceptación por parte de la Real Academia Española. Cada uno es acompañado por la opción correcta (a veces con una breve justificación del término sugerido), cuyo uso se ilustra con un ejemplo en cada caso. Asimismo, aparte de estos errores propiamente idiomáticos, se incluye una breve lista de ciertos errores de concepto, también comunes, cuyo correcto uso es explicado.

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In Latin America and the Caribbean, precious wood species like mahoganies (Swietenia spp.) and cedars (Cedrela spp.) are seriously injured by the mahogany shootborer, Hypsipyla grandella (Zeller) (Lepidoptera: Pyralidae) larva, which bores into the main shoot of trees. In previous experiments focused on searching for a preventive method for managing this pest, a wood extract of bitterwood, Quassia amara L. ex Blom (Simaroubaceae) had been shown to cause phagodeterrence to larvae. Therefore, three fractions (water, methanol and diethyl ether) of a wood extract were tested for their phagodeterrence to larvae, by means of laboratory and greenhouse trials. Phagodeterrence was assessed by determining their effect on foliage consumption, mortality and signs of damage (number of orifices, sawdust piles, fallen shoots, number of tunnels and tunnel length) caused by larvae on Spanish cedar (C. odorata). Both the methanol and diethyl ether fractions caused phagodeterrence, by strongly reducing foliage consumption and signs of damage, while not causing larval mortality. The lowest concentration at which phagodeterrence was detected for the methanol fraction corresponded to 0.0625%, which is equivalent to a 1.0% of the bitterwood crude extract. However, results with the diethyl ether fraction were unsatisfactory, as none of the treatments differed from the solvent, possibly because of an adverse effect of the solvent on foliar tissues. Phagodeterrent principles from Q. amara derivatives may play an important role in dealing with H. grandella if they are complemented with other integrated pest management preventative tactics.

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The density of colonies of leaf-cutting ants, Atta cephalotes L. (Hymenoptera: Formicidae), was measured and compared among coffee (Coffea arabica L.) plantations in five management categories: monoculture conventional, diversified conventional, diversified organic, highly diversified conventional, and highly diversified organic. Twenty-four small farms (<4 ha) in Turrialba, Costa Rica, were included in this study. Within-farm and off-farm (landscape) variables were measured and tested for their relationship with A. cephalotes colony density. Total ant colony density (colonies per ha) and density of new colonies shortly after a nuptial flight were significantly greater in the coffee monoculture conventional system, compared with all other systems. Total ant colony density and density of new colonies were inversely related to percentage of shade within the farms. Within farms, colony density was greater near edges adjacent to riparian forest than those adjacent to nonforested land. Regardless of edge type, plots closer to the edge (0-30 m) had greater colony density than those furthest from the edge. At the landscape scale, density of new colonies was positively related to fallow land use coverage within a 2,000-m buffer radius and to forest coverage within a 500-m radius. Results indicate that coffee farm management practices and landscape level factors can affect A. cephalotes colony densities. Understanding such practices and factors could assist in the development of better management methods of these injurious insects in coffee farms. Increased diversification in coffee farms, possibly due to the greater shade associated with it, may reduce colonization by the ants, which are considered forest gap specialists.

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In Latin America and the Caribbean, precious wood species like mahoganies (Swietenia spp.) and cedars (Cedrela spp.) are seriously injured by the mahogany shootborer, Hypsipyla grandella (Zeller) (Lepidoptera: Pyralidae) larva, which bores into the main shoot of trees. In previous experiments focused on searching for a preventive method for managing this pest, a wood extract of bitterwood, Quassia amara L. ex Blom (Simaroubaceae) had been shown to cause phagodeterrence to larvae. Therefore, three fractions (water, methanol and diethyl ether) of a wood extract were tested for their phagodeterrence to larvae, by means of laboratory and greenhouse trials. Phagodeterrence was assessed by determining their effect on foliage consumption, mortality and signs of damage (number of orifices, sawdust piles, fallen shoots, number of tunnels and tunnel length) caused by larvae on Spanish cedar (C. odorata). Both the methanol and diethyl ether fractions caused phagodeterrence, by strongly reducing foliage consumption and signs of damage, while not causing larval mortality. The lowest concentration at which phagodeterrence was detected for the methanol fraction corresponded to 0.0625%, which is equivalent to a 1.0% of the bitterwood crude extract. However, results with the diethyl ether fraction were unsatisfactory, as none of the treatments differed from the solvent, possibly because of an adverse effect of the solvent on foliar tissues. Phagodeterrent principles from Q. amara derivatives may play an important role in dealing with H. grandella if they are complemented with other integrated pest management preventative tactics. Rev. Biol. Trop. 59 (1): 487-499. Epub 2011 March 01.

En América Latina y el Caribe, algunas especies que son fuente de maderas preciosas, como las caobas (Swietenia spp.) y cedros (Cedrela spp.), son seriamente dañadas por la larva de Hypsipyla grandella, la cual barrena el brote principal de los árboles. En experimentos previos orientados hacia la búsqueda de un método preventivo para manejar esta plaga, un extracto de la madera de hombre grande, Quassia amara (Simaroubaceae), había demostrado causar fagodisuasión a la larva. Por tanto, tres fracciones de un extracto de la madera de dicho árbol (agua, metanol y éter dietílico) fueron evaluadas en cuanto a su efecto fagodisuasivo sobre las larvas, mediante experimentos de laboratorio e invernadero. Dicho efecto se determinó según el consumo de follaje, la mortalidad y los signos de daño (número de orificios, montículos, brotes caídos, número y longitud de túneles) causados por las larvas en arbolitos de cedro amargo (C. odorata). Tanto la fracción de metanol como la de éter dietílico causaron fagodisuasión, pues redujeron fuertemente el consumo de follaje y los signos de daño, sin matar las larvas. La menor concentración de la fracción metanólica a la cual se detectó fagodisuasión correspondió a 0.0625%, la cual equivale al 1.0% del extracto crudo de hombre grande. Por su parte, los resultados con la fracción de éter dietílico fueron insatisfactorios, ya que ninguna de las concentraciones difirió del disolvente, quizás debido a un efecto adverso del mismo sobre los tejidos foliares. Los principios fagodisuasivos de los derivados Q. amara podrían jugar un papel importante para manejar a H. grandella, si fueran complementados con otras tácticas preventivas de manejo integrado de plagas.

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The susceptible species Cedrela odorata and Swietenia macrophylla to attack by Hypsipyla grandella (Zeller) larvae were grafted onto the resistant species Khaya senegalensis and Toona ciliata. Six-month-old grafted plants were then compared to their reciprocal grafts and to both intact (non-grafted) and autografted plants for damage due to H. grandella larvae and for their effects on larval performance. Two experiments were conducted: one in which the apical bud of the main plant shoot was inoculated with H. grandella eggs, and the other in which the bud was inoculated with third instars. Damage in each experiment was assessed by the number of frass piles, number and length of tunnels, number of damaged leaves, and damage to the apical bud. Larval performance was evaluated in terms of time to reach pupation and pupal weight and length. In both experiments, plant damage differed significantly among treatments (P < 0.03). Resistant rootstocks conferred resistance to susceptible scions. In both experiments, grafting by itself, regardless of the rootstock and scion combination, also reduced damage caused by H. grandella larvae. Scions of autografted susceptible species had similar resistance to susceptible scions grafted on resistant rootstocks. Few larvae reached pupation, and their pupal weight and length were similar.

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The susceptible species Cedrela odorata and Swietenia macrophylla to attack by Hypsipyla grandella (Zeller) larvae were grafted onto the resistant species Khaya senegalensis and Toona ciliata. Six-month-old grafted plants were then compared to their reciprocal grafts and to both intact (non-grafted) and autografted plants for damage due to H. grandella larvae and for their effects on larval performance. Two experiments were conducted: one in which the apical bud of the main plant shoot was inoculated with H. grandella eggs, and the other in which the bud was inoculated with third instars. Damage in each experiment was assessed by the number of frass piles, number and length of tunnels, number of damaged leaves, and damage to the apical bud. Larval performance was evaluated in terms of time to reach pupation and pupal weight and length. In both experiments, plant damage differed significantly among treatments (P < 0.03). Resistant rootstocks conferred resistance to susceptible scions. In both experiments, grafting by itself, regardless of the rootstock and scion combination, also reduced damage caused by H. grandella larvae. Scions of autografted susceptible species had similar resistance to susceptible scions grafted on resistant rootstocks. Few larvae reached pupation, and their pupal weight and length were similar.

Assuntos

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Hypsipyla grandella (Zeller) larva is maybe the main forest pest in Latin America and the Caribbean, as it bores into the main shoot of trees providing precious woods, such as mahoganies (Swietenia spp.) and cedars (Cedrela spp.). In the search for a preventative method for managing it, the crude leaf extract of common rue (Ruta chalepensis L.), as well as four partitions thereof (water, hexane, dichlorometane, and ethyl acetate), were tested for phagodeterrence. Laboratory bioassays involved increasing concentrations of the crude extract (0.1, 0.32, 1.0, 3.20 and 10.0%w/v) as well as each one of the partitions (in accordance to the yield obtained from the partitioning process), plus rutin, a flavone glycosid. A randomized complete block design, with four replicates, was used. H. grandella instar III larvae were exposed for 24 h to cedar (Cedrela odorata) leaf discs dipped into the respective treatment, after which disc consumption was measured. Strong phagodeterrence was detected at concentrations as low as 0.32 and 0.074%w/v for the crude extract and the hexane partitions, respectively; the ethyl acetate (0.24%w/v) and the water partition (for all of its concentrations), as well as the rutin (starting at 0.064%w/v), caused phagodeterrence, too. Moreover, the crude extract was submitted to a phytochemical screening by means of a number of qualitative tests, to determine possible metabolites causing phagodeterrence, the most important being alkaloids, triterpenes, coumarins and rutin. A particular phytochemical screening was carried out for the hexane partition, which was the most active.

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