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Fires impact ecosystems globally and due to climate change, the frequency of high-severity fires has increased. As ecosystems change with altered fire regimes, changes in the communities that provide ecosystem services, such as pollination, have been reported. We studied fires with mixed-severity types that burned >20 years ago and compared insect floral visitor communities by focusing on an important floral resource, wax currant (Ribes cereum). Simultaneously, we conducted a pollinator exclusion experiment to determine how floral visitors impact fruit production of wax currant. Importantly, the pollinator community of wax currant is virtually unknown with only a single study that was conducted in a riparian ecosystem. We found that there was no difference in the floral visitor communities or fruit production of wax currant plants across fire severity, but our sample sizes were small. Notably, we found that the pollinator exclusion treatment had a significant impact on fruit production of wax currant plants, especially early season pollinators, which demonstrates the importance of insect pollinators across all fire severities for wax currant plants. Resumen Los incendios impactan los ecosistemas a nivel mundial y debido al cambio climático, hay aumentos en la frecuencia de aquellos de alta gravedad. A medida que los ecosistemas cambian con regímenes de incendios alterados, se han reportado efectos en las comunidades que brindan servicios ecosistémicos, como la polinización. Estudiamos incendios de gravedad mixta que ardieron hace más de 20 años y comparamos comunidades de insectos visitantes de flores en diferentes niveles de gravedad del incendio, centrándonos en un importante recurso floral, la grosella cera (Ribes cereum). Simultáneamente, llevamos a cabo un experimento de exclusión de polinizadores para determinar cómo los visitantes florales impactan el amarre de la grosella cera. La comunidad polinizadora de la grosella cerosa es prácticamente desconocida y solo se ha realizado otro estudio en un ecosistema ribereño. Descubrimos que no había diferencias en las comunidades de visitantes florales o en el amarre de frutos de las plantas de grosella cera según la gravedad del incendio, pero los tamaños de nuestras muestras fueron pequeños. Encontramos que el tratamiento de exclusión de polinizadores tuvo un impacto significativo en amarre de frutos de las plantas de grosella cera, especialmente en los polinizadores tempranos, lo que demuestra la importancia de los insectos polinizadores en todas las severidades de los incendios para las plantas de grosella cera. [ABSTRACT FROM AUTHOR]

A new species of Sesioctonus (Braconidae: Agathidinae), Sesioctonus alvaradae sp. nov. from Peru, is described and illustrated. With the addition of this new species, Sesioctonus genus has 36 species. [ABSTRACT FROM AUTHOR]

Mosquitoes represent the most important agent disseminating infectious diseases like yellow fever, dengue, chikungunya, and malaria, among others. An essential strategy for its control is killing them at immature stages using industrial insecticides. However, those chemicals often generate resistance and affect the environment and human health. Agricultural and plant by-products constitute a new sustainable option to obtain harmless and eco-friendly bioinsecticides to prevent mosquitoes from spreading. This study aimed to investigate the phytochemical profile of Persea americana Mill (Lauraceae) seed extracts and their insecticide activity against Aedes aegypti at larval and pupal stages. The ethanol extracts from avocado seeds were obtained by Maceration/stirring (MaE) and Soxhlet extraction (SE) methods. The main chemical profile was determined by quantitative and UPLC assays. Insecticide activity was assessed by the exposition of mosquitoes at larval and pupal stages to seed extracts. Human cell lines were used to evaluate the cytotoxicity. Soxhlet methodology was more efficient in the extraction of P. americana seeds metabolites (42.13±1.76 mg/mL) compared with MaE (20.46±1.66 mg/mL) (p< 0.05). Additionally, SE showed a higher amount of polyphenols (5.12±0.18 mg/mL). The UPLC spectra analysis revealed the presence of polyphenols, mainly catechin, and neolignan constituents. Both extracts showed larvicidal and pupicidal effects, but SE was more active at lower concentrations. Moreover, no significant toxic effects on human monocytes and fibroblast cell lines were found after treatment. In sum, avocado seed by-products can be considered an eco-friendly insecticide and its use may help to substantially decrease the vector-transmitted diseases in developing countries. [ABSTRACT FROM AUTHOR]

The cactus weevil (Metamasius spinolae) is a pest of Opuntia ficus-indica. It can develop not only in Opuntia species but also in other cacti and members of the Asparagaceae family. In 2017, damage and presence of adult insects with characteristics similar to the cactus weevil were reported in two species of cacti, Austrocylindropuntia subulata and Peniocereus serpentinus. The objective was to identify the insect and determine if the two cacti species are hosts, field and laboratory research was conducted from 2017 to 2019 in the municipality of Axapusco, State of Mexico. Stems with larval damage were selected at four study sites, whic remained in field conditions until the emergence of adult insects. The behaviour of M. spinolae on the host plant, mating sites, incubation period and damage development over time were recorded. M. spinolae was identified and determined to fulfill its life cycle on A. subulata and P. serpentinus. Larvae cause the most damage by feeding on the internal part (pith) of the stems, which causes tissue rotting and death of the affected part. The adult feeds on tender buds and mature stems, causing deformation and weakening of the plant. The two cacti species proved to be host plants that can harbour populations of M. spinolae and, therefore, have a high potential to act as reservoirs of the pest, which can then migrate to prickly-pear cactus crop. This report expands the knowledge of hosts of the cactus weevil. The information obtained shall be useful for vegetable growers to apply phytosanitary measures in alternate hosts, combat reservoirs and avoid re-infestations of the pest. [ABSTRACT FROM AUTHOR]

Objective: To analyze the perception of sorghum producers about the incidence and damage of the yellow aphid and its natural enemies, as well as the control methods to strengthen integrated management strategies and reduce damage caused by the aphid in three localities of the Pueblan region that produce this grain. Methodology: Through convenience sampling and an interview guide, information was collected from 44 producers attending meetings held by the State Plant Health Committee. Results: The sorghum crop was rainfed. The major problems that the producers identified in sorghum were four, 66% pointed to the yellow aphid as the main one. The producers perceived infestation in all their plots at different stages of cultivation. Chemical insecticides were mainly used to control the aphid, followed by the combination with natural enemies. 77% observed natural enemies of the aphid in their plot, of which lady beetles and hoverflies had a greater presence. 70% indicated that natural enemies are threatened by the high doses of insecticides applied. Limitations: Although the study was carried out in three locations, it allowed us to understand the main elements of the phenomenon studied. Conclusions: The producers perceived and identified the yellow sorghum aphid as the main problem of the crop, and it affected the entire surface. They specified the presence of at least one natural enemy in their plot. However, the high application of insecticides has adverse effects on them, findings that reflect an important biological potential to be used in aphid management. [ABSTRACT FROM AUTHOR]

We describe a portable, economical plastic chamber for observations on development and reproduction of potato-tomato psyllid, Bactericera cockerelli for up to a few wk on plant material under controlled conditions. It can be used for other insects as well. Se describe una cámara de plástico portátil y económica para observaciones durante semanas del desarrollo y reproducción de el psílido de la papa y tomate, Bactericera cockerelli en material vegetal bajo condiciones controladas. Esta cámara también se puede utilizar para otros insectos. [ABSTRACT FROM AUTHOR]

The bean flower thrips, Megalurothrips usitatus (Bagnall) (Thysanoptera: Thripidae) is native from Asia and is a well-known pest of legumes such as common bean (Phaseolus vulgaris L.), cowpea (Vigna unguiculata [L.] Walp.), pea (Pisum sativum L.), and lima bean (Phaseolus limensis Macf.) (all Fabaceae). This thrips species has been recorded recently in the Americas (USA and Cuba). Before this study there were no records of M. usitatus in Mexico; this work is the first report of M. usitatus in Mexico. We found this species attacking common beans, jicama, and cowpeas in Nayarit State. In cowpeas, it reduced production by at least 60%. The highest population was observed in jicama but no evidence of severe damage or yield loss was documented; however, the potential damage on the seed production should be evaluated. Authorities, researchers, extension agents, and growers should work together to prevent the dispersal of this pest, which may infest other economically important legumes. Chances of controlling or eradicating M. usitatus in the region are minimal if no effective alternatives are available in the short term. El trips de la flor del frijol, Megalurothrips usitatus (Bagnall) (Thysanoptera: Thripidae) es originario de Asia y es una conocida plaga de leguminosas como el frijol común (Phaseolus vulgaris L.), el caupí (Vigna unguiculata [L.] Walp.), guisante (Pisum sativum L.) y frijol lima (Phaseolus limensis Macf.) (todas Fabaceae). Esta especie de trips ha sido registrada recientemente en las Américas (EE.UU. y Cuba). Antes de este estudio no había registros de M. usitatus en México; este trabajo es el primer reporte de M. usitatus en México. Encontramos esta especie atacando frijol común, jícama y caupí en el estado de Nayarit. En caupí, redujo la producción en al menos un 60%. La población más alta se observó en jícama pero no se documentó evidencia de daño severo o pérdida de rendimiento; sin embargo, se debe evaluar el daño potencial sobre la producción de semillas. Las autoridades, investigadores, extensionistas y productores deben trabajar juntos para evitar la dispersión de esta plaga, que puede infestar otras leguminosas económicamente importantes. Las posibilidades de controlar o erradicar M. usitatus en la región son mínimas si no se dispone de alternativas eficaces a corto plazo. [ABSTRACT FROM AUTHOR]

Acerola (Malpighia emarginata DC.) is a shrub species that grows in tropical and subtropical climates; it is native to southern Mexico, Central America and northern South America. Its fruits have a high vitamin C content and are considered one of the most potent and least toxic natural antioxidants. Among the main pest species causing crop damage is the genus Anthonomus (Coleoptera: Curculionidae). In 2019, surveys were conducted in the western region of Cuba to evaluate the presence of pests in plants located in the localities of Alquizar and Ceiba del Agua, belonging to the province of Artemisa. They collected 100 flowers and 100 green fruits of different sizes that presented deformations and symptoms characteristic of damage caused by an insect. A total of 344 holes were counted, for an average of 3.4 holes per fruit; in addition, 230 larvae, 114 eggs, 65 pupae and 81 adults of a coleopteran. The objective of the work was to identify the species of the insect associated with the observed damage. The morphological characters of the collected insect allowed the identification of Anthonomus sisyphus Clark as the cause of damage to acerola fruits and constitutes the first report of this species as a pest of this fruit tree in Cuba. [ABSTRACT FROM AUTHOR]

Pagiocerus frontalis (Fabricius) (Coleoptera: Curculionidae) is known to feed on stored grains, especially corn Zea mays L. (Poaceae). No reports are available of this borer feeding on avocado seeds (Persea americana Mill.; Lauraceae), which is one of the most economically important crops exported by Mexico. In 2019, this coleopteran was extraordinarily abundant (about 30 adults per avocado seed) in an avocado orchard located in Nayarit, Mexico. We found that this insect feeds on mature fallen avocados. Biological and behavioral aspects of P. frontalis still are largely unknown on avocado fruits. This study documented the natural occurrence of this species on avocado seeds in Nayarit, Mexico. [ABSTRACT FROM AUTHOR]