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1.
Insects ; 15(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38392543

RESUMO

The rainfall regime has a significant impact on the microclimate and mass emergence of the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae) (CBB). Little is known, however, about the shade tree-microclimate-CBB mass emergence interaction. The objective of the present study was to compare the effect of microclimate on the mass emergence of CBB in a full sun-exposed plot with a plot shaded by trees. The experiment was conducted on a Robusta coffee farm in southern Chiapas, Mexico. In each plot, 18 traps baited with an alcohol mixture were installed to capture flying females, collecting caught individuals every hour from 8:00 to 18:00 h. A meteorological station recorded several microclimatic variables on 13 weekly sampling dates from February to May 2022. Significantly more CBB females were captured in the shaded plot. The largest number of CBB captures was recorded between 14:00 and 16:00 h for the shade plot and between 15:00 and 17:00 h for the sun-exposed plot. The mass emergence of CBB showed a positive association with precipitation, dew point, and wind speed samples and a negative association with maximum air temperature, average relative humidity, ultraviolet radiation, wind speed, and equilibrium moisture content. Our observations show that the relationship between shade trees, microclimate, and mass emergence of CBB is complex and that its study helps us to gain deeper insight into CBB bioecology and advance control techniques against this important pest.

2.
Artigo em Inglês | MEDLINE | ID: mdl-30257443

RESUMO

Acute and sub-acute effects of pesticide use in coffee farmers have rarely been investigated. In the present field study, self-reported health symptoms from 38 male pesticide users were compared to those of 33 organic farmers. Results of cytological findings have been reported in an accompanying paper in this issue. The present second part of the study comprises a questionnaire based survey for various, potentially pesticide related symptoms among the coffee farmers. Symptom rates were generally higher in exposed workers, reaching significance in nine out of 19 assessed symptoms. Significantly increased symptom frequencies were related to neurotoxicity, parasympathic effects and acetylcholine esterase inhibition, with the highest differences found for excessive salivation, dizziness and stomach ache. We revealed a lack of precautionary measures in the majority of farmers. Better education, regulations, and safety equipment are urgently needed.


Assuntos
Doenças dos Trabalhadores Agrícolas/epidemiologia , Doenças dos Trabalhadores Agrícolas/patologia , Café , Fazendeiros/estatística & dados numéricos , Exposição Ocupacional/estatística & dados numéricos , Praguicidas/toxicidade , Adulto , Idoso , Doenças dos Trabalhadores Agrícolas/fisiopatologia , República Dominicana/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Praguicidas/classificação , Inquéritos e Questionários
3.
Artigo em Inglês | MEDLINE | ID: mdl-30081446

RESUMO

Intensive agrochemical use in coffee production in the Global South has been documented. The aim of this study was to investigate cytotoxic and genotoxic effects of pesticide exposure in male farmworkers in the Dominican Republic comparing conventional farming using pesticides to organic farming. Furthermore, feasibility of the buccal micronucleus cytome assay (BMCA) for field studies under difficult local conditions was tested. In a cross-sectional field study, pesticide exposed (sprayers) and non-exposed male workers on coffee plantations were interviewed about exposure history, and pesticide application practices. Buccal cells were sampled, and BMCA was applied to assess potential effects on cell integrity. In total, 38 pesticide-exposed and 33 non-exposed workers participated. Eighty-four and 87%, respectively, of the pesticide-exposed respondents did not use masks or gloves at all. All biomarkers from the BMCA were significantly more frequent among exposed workers-odds ratio for micronucleated cells: 3.1 (95% confidence interval: 1.3⁻7.4) or karyolysis: 1.3 (1.1⁻1.5). Buccal cells as sensitive markers of toxic oral or respiratory exposures proved feasible for challenging field studies. Our findings indicate that the impact of pesticide use is not restricted to acute effects on health and wellbeing, but also points to long-term health risks. Therefore, occupational safety measures including training and protective clothing are needed, as well as encouragement towards minimal application of pesticides and more widespread use of organic farming.


Assuntos
Café , Dano ao DNA , Fazendeiros , Exposição Ocupacional/efeitos adversos , Praguicidas/toxicidade , Adulto , Agricultura/métodos , Estudos de Casos e Controles , Estudos Transversais , República Dominicana , Estudos de Viabilidade , Humanos , Masculino , Testes para Micronúcleos , Mucosa Bucal/efeitos dos fármacos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/estatística & dados numéricos , Roupa de Proteção , Risco
4.
J Med Entomol ; 55(1): 172-182, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29186487

RESUMO

This is the first complete assessment of the ectoparasite fauna on phyllostomid bats in a shaded coffee plantation in Mexico. The study was carried out at Finca San Carlos, in the municipality of Tapachula, southeastern Chiapas, Mexico. The bats were captured over three consecutive nights every month, from December 2005 to November 2006, using four mist nets. We captured 192 phyllostomid bats, representing 18 species, upon which 1,971 ectoparasites, belonging to 11 families and 65 species, were found. We found that 160 of the 192 captured bats were hosts to ectoparasites, giving an infestation prevalence of 83.3%. Of the 65 ectoparasitic species, 14 were classified as monoxenous and 17 as stenoxenous. More ectoparasites were recorded in the dry season (n = 1,439) than the wet season (n = 532), and we recorded some families of ectoparasite on particular areas of the bat body. An ordination of bat species, based on their ectoparasitic species community structure, formed groups at the subfamily level or lower taxonomic categories. We suggest that the close ectoparasite-host relationships could be examined as an additional tool to elucidate the taxonomic relationships between the hosts.


Assuntos
Quirópteros , Dípteros/fisiologia , Ectoparasitoses/veterinária , Ácaros/fisiologia , Distribuição Animal , Animais , Coffea/crescimento & desenvolvimento , Produção Agrícola , Ectoparasitoses/epidemiologia , Ectoparasitoses/parasitologia , Interações Hospedeiro-Parasita , México/epidemiologia , Prevalência , Estações do Ano
5.
Sensors (Basel) ; 17(4)2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28383494

RESUMO

Smartphones show potential for controlling and monitoring variables in agriculture. Their processing capacity, instrumentation, connectivity, low cost, and accessibility allow farmers (among other users in rural areas) to operate them easily with applications adjusted to their specific needs. In this investigation, the integration of inertial sensors, a GPS, and a camera are presented for the monitoring of a coffee crop. An Android-based application was developed with two operating modes: (i) Navigation: for georeferencing trees, which can be as close as 0.5 m from each other; and (ii) Acquisition: control of video acquisition, based on the movement of the mobile device over a branch, and measurement of image quality, using clarity indexes to select the most appropriate frames for application in future processes. The integration of inertial sensors in navigation mode, shows a mean relative error of ±0.15 m, and total error ±5.15 m. In acquisition mode, the system correctly identifies the beginning and end of mobile phone movement in 99% of cases, and image quality is determined by means of a sharpness factor which measures blurriness. With the developed system, it will be possible to obtain georeferenced information about coffee trees, such as their production, nutritional state, and presence of plagues or diseases.

6.
Acta biol. colomb ; 21(2): 399-412, mai.-ago. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-781907

RESUMO

Se determinaron los cambios en composición, densidad y distribución espacial de la edafofauna de hojarasca entre dos usos de suelo (cafetal y bosque subandino) para entender el efecto del uso de suelo. Asimismo, se establecieron las relaciones entre las variables de la edafofauna y atributos de la hojarasca. Se colectaron muestras de hojarasca superficial durante la época seca y se extrajo la edafofauna, manualmente y mediante embudos Berlese modificados. Esta se identificó hasta el menor nivel taxonómico posible y se clasificó en grupos funcionales. La composición faunística fue diferente entre los usos de suelo. La similitud en la composición fue menor al 50 % en dos de los tres grupos funcionales encontrados, pero la densidad total no presentó diferencias. En general hubo coeficientes de variación altos en la densidad faunística intermuestral para los diferentes grupos taxonómicos y, en consecuencia, una baja detectabilidad del patrón espacial. Sin embargo, se detectó un patrón espacial en la abundancia para Coleoptera, larvas de Diptera y biomasa de hojarasca, en el cafetal. La estructura fue más difícil de detectar en bosque, por los pequeños parches en este. La varianza de la abundancia fue mayor en el cafetal, para todos los grupos, excepto Acaridida y Formicidae. La densidad de Formicidae aumentó al hacerlo la humedad de la hojarasca, pero solo en cafetal. Se concluye que el establecimiento del cafetal afecta de manera diferencial a taxones y grupos funcionales de la edafofauna. Esto sienta las bases para definir los efectos del cambio de uso de suelo y los factores ambientales asociados con la distribución espacial de la edafofauna.


Changes in composition, density and spatial distribution on the litter edaphic fauna between two land uses (a coffee plantation and a tropical Andean forest) were established, in order to understand the soil use effects. Also, the relationships between the biotic variables and some litter features were evaluated. Superficial litter samples were collected during dry season. The edaphic fauna was extracted manually and with modified Berlese funnels; it was identified up to the lower taxonomic level and classified in functional groups. Differences in fauna composition were observed between the two land uses. Composition similarity was lower than 50 % for almost all functional groups found, but total density did not differ between the land uses. In general, there was a high variation in density among samples resulting in higher coefficients of variation for different taxonomic groups and consequently low detectability of spatial pattern. However a spatial pattern was detected only for Coleoptera, Diptera larvae and litter biomass in the coffee plantation. The structure in forest was more difficult to detect, due to the smaller patches on it. The variance of abundance was significantly higher in the coffee plantation for all groups, except Acaridida and Formicidae. Density of Formicidae increased with the enhancement of litter moisture, but only in the coffee plantation. In conclusion, the establishment of coffee plantation differentially affects taxa and functional groups of soil fauna. This is the basis for establishing the effects of soil change use, and the environmental factors associated with spatial distribution of edaphic fauna.

7.
Rev. biol. trop ; Rev. biol. trop;64(1): 221-233, ene.-mar. 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-843273

RESUMO

ResumenLa zorra gris (Urocyon cinereoargenteus Schreber) es un cánido de tamaño mediano que se distribuye ampliamente en México. La mayoría de los estudios sobre esta especie se han enfocado en el uso de hábitat, el ámbito hogareño, la dieta, la competencia con otros carnívoros y su distribución en diferentes paisajes tanto urbanos como rurales. Se tiene conocimiento de su presencia en fragmentos de bosque mesófilo de montaña y cafetales de sombra en el centro de Veracruz, aunque no se ha comparado su abundancia con otras coberturas vegetales como los cultivos presentes en la región. En este estudio describimos las variaciones de la abundancia mensual de zorra gris a través del registro de excretas en transectos de 500 m en cañaverales, cafetales de sombra y fragmentos de bosque mesófilo de montaña entre octubre del 2008 y mayo del 2009. Reportamos el índice de abundancia relativa para cada cobertura y cada mes, y evaluamos la relación de cuatro variables del paisaje (porcentaje de sombra, densidad de caminos, densidad de población humana y entremezcla de hábitats) en áreas de influencia de 450 ha alrededor de los sitios de muestreo. La comparación de la abundancia entre coberturas, mostró abundancias menores en los fragmentos de bosque mesófilo y mayores en los cafetales de sombra y cañaverales. No se encontró diferencia significativa a través de los meses (P= 0.476). Se plantea que la abundancia mayor en los cultivos puede estar asociada a las plagas de roedores y a la presencia de árboles frutales que ofrecen alimento a la zorra gris. De las variables del paisaje evaluadas solo la densidad de caminos de impacto medio y la densidad de población se correlacionaron positivamente con la abundancia de zorra gris, lo que demuestra que puede cohabitar con el humano sobre todo en zonas rurales. Se destaca la capacidad de la zorra gris para aprovechar los paisajes heterogéneos.


AbstractThe gray fox, Urocyon cinereoargenteus, is a medium-size canid widely distributed in México. Most studies on this species focus on habitat use, home range, diet, intraguild competence, and lanscape distribution between urban and rural sites. In central Veracruz, gray foxes are present in fragments of cloud forest and in shaded coffee plantations; nevertheless, its abundance has not yet been compared among other vegetation types found in the area, such as sugarcane plantations. In this study we described gray foxes abundance variations using 500 m transects, among sugarcane plantations, shaded coffee plantations, and cloud forest fragments throughout eight months, by scat counting in three sites of each cover type. We reported the relative abundance index for each cover type and each month, and evaluated its relationship with four landscape features: (a) shade percent, (b) trail density, (c) human population density, and (d) habitat juxtaposition, in influence areas of 450 ha around sampling sites. Abundance comparison among cover types showed lower abundances in cloud forest fragments and higher abundances in coffee and sugarcane plantations. No significant differences were found throughout months (p = 0.476). We proposed that higher abundances in plantations may be related to the presence of rodent plagues and fruit trees which offer food resources to gray foxes. The evaluation of landscape features showed that only medium-impact trail density and human population density were positively correlated with gray fox abundance; fact that demonstrates that this canid can coexist with humans in rural sites. We highlight the gray fox capacity to take advantage of heterogeneous landscapes.


Assuntos
Animais , Ecossistema , Raposas , Florestas , Densidade Demográfica , México
8.
Braz. j. biol ; Braz. j. biol;69(2): 305-309, May 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-519171

RESUMO

Between May 2002 and May 2003, we studied a small mammal community from an Atlantic forest fragment surrounded by a coffee plantation in the municipality of Santa Teresa, Espírito Santo state, Brazil. We obtained a total of 300 captures of 114 individuals belonging to 11 mammal species. Seventy three percent of the species captured in the forest also used the coffee plantation, mainly males (90%) and young (80%) individuals of Marmosops incanus. The exceptionally low recapture rate in the coffee plantation suggests that it functions as a corridor between fragments, rather than as a habitat for these species. Understanding the role of matrix habitat use in fragmented landscapes is an important factor in small mammal conservation, as it asymmetrically affects the rate and mode of individual movements of different species.


Entre março de 2002 e abril de 2003, estudamos uma comunidade de pequenos mamíferos em um fragmento de Floresta Atlântica cercado por plantação de café no município de Santa Teresa, estado do Espírito Santo, Brasil. Obtivemos um total de 300 capturas de 114 indivíduos pertencentes a 11 espécies de mamíferos. Setenta e três por cento das espécies capturadas na floresta também usaram a plantação de café, principalmente indivíduos machos (90%) e jovens (80%) de Marmosops incanus. A taxa de recaptura excepcionalmente baixa na plantação de café sugere que este possa funcionar como um corredor entre os fragmentos, e não como habitats para as espécies. Entender como é o uso da matriz de habitats em paisagens fragmentadas é um importante fator na conservação de pequenos mamíferos, uma vez que ele afeta assimetricamente a taxa e o modo de movimento de indivíduos de diferentes espécies.


Assuntos
Animais , Feminino , Masculino , Biodiversidade , Mamíferos/classificação , Brasil , Densidade Demográfica , Árvores
9.
Braz. J. Biol. ; 69(2)2009.
Artigo em Inglês | VETINDEX | ID: vti-446533

RESUMO

Between May 2002 and May 2003, we studied a small mammal community from an Atlantic forest fragment surrounded by a coffee plantation in the municipality of Santa Teresa, Espírito Santo state, Brazil. We obtained a total of 300 captures of 114 individuals belonging to 11 mammal species. Seventy three percent of the species captured in the forest also used the coffee plantation, mainly males (90%) and young (80%) individuals of Marmosops incanus. The exceptionally low recapture rate in the coffee plantation suggests that it functions as a corridor between fragments, rather than as a habitat for these species. Understanding the role of matrix habitat use in fragmented landscapes is an important factor in small mammal conservation, as it asymmetrically affects the rate and mode of individual movements of different species.


Entre março de 2002 e abril de 2003, estudamos uma comunidade de pequenos mamíferos em um fragmento de Floresta Atlântica cercado por plantação de café no município de Santa Teresa, estado do Espírito Santo, Brasil. Obtivemos um total de 300 capturas de 114 indivíduos pertencentes a 11 espécies de mamíferos. Setenta e três por cento das espécies capturadas na floresta também usaram a plantação de café, principalmente indivíduos machos (90%) e jovens (80%) de Marmosops incanus. A taxa de recaptura excepcionalmente baixa na plantação de café sugere que este possa funcionar como um corredor entre os fragmentos, e não como habitats para as espécies. Entender como é o uso da matriz de habitats em paisagens fragmentadas é um importante fator na conservação de pequenos mamíferos, uma vez que ele afeta assimetricamente a taxa e o modo de movimento de indivíduos de diferentes espécies.

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