RESUMEN

In Brazil, most studies involving parasites of bats (bat flies) treat the mid-west, south-east, and south of the country. This work aimed to characterize the ectoparasites community associated with bats in the Atlantic forest in the state of Sergipe, north-eastern Brazil. Sampling was conducted between January and June 2013 in the Serra de Itabaiana National Park (PNSI) and between November 2013 and June 2015 in the Wildlife Refuge Mata do Junco (RVSMJ). Parasitological indexes were determined, and the influence of host sex and the seasonality in prevalence rates and mean intensity for the most abundant parasites was evaluated. Some 129 parasites were collected in PNSI and 296 in RVSMJ, and 100 and 70.6 %, respectively, belong to the family Streblidae. The differences in parasitological rates in Sergipe in relation to other studies may be associated with the environmental characteristics and the composition of the host community. The influence of sex and the seasonal prevalence of Speiseria ambigua and Trichobius joblingi, associated with Carollia perspicillata, may be associated with a lower rate of female captures and low sampling in the dry season. This is a pioneer study in Sergipe that reveals the occurrence of 16 species of streblids and representatives of Acari and Basilia spp., highlighting the need for more studies to increase the wealth and understanding of host-parasite associations in the state.

Asunto(s)

Ácaros y Garrapatas/fisiología , Quirópteros/parasitología , Dípteros/fisiología , Infestaciones Ectoparasitarias/veterinaria , Ácaros y Garrapatas/clasificación , Animales , Animales Salvajes/parasitología , Brasil/epidemiología , Dípteros/clasificación , Infestaciones Ectoparasitarias/parasitología , Femenino , Bosques , Interacciones Huésped-Parásitos , Masculino , Parques Recreativos , Prevalencia , Estaciones del Año

RESUMEN

The mite Allopsoroptoides galli has recently been identified parasitizing commercial chickens, São Paulo State/Brasil, causing severe dermatitis on all parts of the animal's body and a significant decline in productivity, particularly in egg production. The aim of the present study in A. galli infestation was to investigate the impact on laying hens' performance and egg quality. A total of 100 56-week-old Hy-line white laying hens were used. The birds were divided into 2 groups, with 10 replicates of 5 birds in each group. The experimental groups consisted of a non-infested group (hens free of theA. galli) and an infested group (hens presenting A. galli). The infestation with A. galli did not significantly influence feed intake but caused a significant reduction in the body weight of the hens and caused a decrease in egg production, therefore promoting worse feed conversion. The egg weight was reduced; however, the infestation did not significantly affect the internal quality of the eggs, which was measured according to the yolk color, albumen height, and Haugh units, or the quality of the shell, based on its percentage, thickness, and strength. It can be concluded that anA. galli infestation promotes a reduction in body weight, egg production, and egg weight in laying hens, therefore worsening feed conversion.

Asunto(s)

Ácaros y Garrapatas/fisiología , Pollos , Infestaciones por Ácaros/veterinaria , Enfermedades de las Aves de Corral/parasitología , Animales , Peso Corporal , Brasil , Femenino , Infestaciones por Ácaros/parasitología , Óvulo/fisiología , Reproducción

RESUMEN

Kaliszewskia ochoai gen. nov., sp. nov. (Tarsonemidae: Tarsoneminae: Tarsonemini) is described from adult females, collected on Blepharocalix salicifolius (Kunth) O.Berg and Plinia sp. (Myrtaceae), from the Atlantic Forest in Brazil.

Asunto(s)

Ácaros y Garrapatas/anatomía & histología , Ácaros y Garrapatas/clasificación , Ácaros y Garrapatas/fisiología , Animales , Brasil , Femenino , Bosques

RESUMEN

Cryptic diversity has been confirmed for several phytophagous mites in the Eriophyoidea superfamily previously considered as presenting low host specificity. Among generalist eriophyoids is the phytoptid Retracrus johnstoni Keifer, which has been reported in 19 palm species belonging to 11 genera, causing severe damage on some of them. Surprisingly this species was recently reported on another monocot family, Heliconiaceae, infesting Heliconia plants in Costa Rica and Brazil, being the only in the tribe Mackiellini to not be associated with palm trees. This study aimed to investigate the occurrence of cryptic species in R. johnstoni and to clarify the taxonomic status of populations associated with heliconias in the Americas. With this purpose traditional and geometric morphometric analyses were conducted as well as a detailed morphological study. Measurable trait data were analysed via univariate and multivariate analyses. Shapes of specimens from different populations were compared via geometric morphometric landmark methods. Morphometric analysis supported occurrence of at least two cryptic species previously identified as R. johsntoni and suggested occurrence of cryptic species among populations associated with different palm trees. Taxonomic descriptions of two new taxa associated with heliconias, namely Retracrus costaricensis n. sp. Ferreira and Navia and Retracrus heliconiae n. sp. Ferreira and Navia are presented. Morphometric traits that can be useful in the taxonomic identification are noted and their value is discussed. Results of the traditional morphometry and geometric methods were compared and the advantages of their joint use for Eriophyoidea systematics are discussed.

Asunto(s)

Ácaros y Garrapatas/anatomía & histología , Ácaros y Garrapatas/clasificación , Ácaros y Garrapatas/crecimiento & desarrollo , Ácaros y Garrapatas/fisiología , Animales , Brasil , Costa Rica , Femenino , Cadena Alimentaria , Heliconiaceae/crecimiento & desarrollo , Larva/anatomía & histología , Larva/clasificación , Larva/fisiología , Masculino , Análisis Multivariante , Ninfa/anatomía & histología , Ninfa/clasificación , Ninfa/fisiología , Especificidad de la Especie

RESUMEN

Brevipalpus phoenicis (Geijskes) is a cosmopolitan and polyphagous mite that transmits important phytoviruses, such as coffee ringspot virus, passion fruit green spot virus and Citrus leprosis virus C. To characterise the dynamics of the probability and the rate of B. phoenicis infestation in response to edaphic and climatic factors, monthly inspections were performed in nine orchards in a citrus region of the State of Bahia, Brazil, for 35 months. Three fruits per plant were examined using a magnifying glass (10×) on 21 plants distributed along a "W"-shaped path in each orchard. Meteorological data were collected from a conventional station. To determine the correlations among the climatic variables, the data were analysed using Spearman correlations. Variables were selected by principal component analysis, and those that contributed the most to differentiate the groups were evaluated via a Mann-Whitney test. Using the quantile-quantile method, the limit values for the following climatic variables were determined: temperature (24.5 °C), photoperiod (12 h), relative humidity (83%), evapotranspiration (71 mm) and rainy days (14 days). The combination of longer days, higher temperatures, lower relative humidity levels and lower evapotranspiration increased the probability of B. phoenicis infestation, whereas successive rain events decreased that risk. Infestation rates were negatively affected by relative humidity levels above 83% and were positively affected by a decreasing available soil-water fraction and increasing insolation and photoperiod.

Asunto(s)

Ácaros y Garrapatas/fisiología , Clima , Suelo/química , Animales , Brasil , Citrus/crecimiento & desarrollo , Cadena Alimentaria , Dinámica Poblacional

RESUMEN

Cultivation of tropical flowers has expanded considerably in Brazil, justifying efforts to determine the arthropods associated with it. Heliconia species are some of the most important tropical flowers in Brazil. Mites of the families Ascidae, Blattisociidae and Melicharidae are commonly found on those plants. They disperse from flower to flower on hummingbirds. The objective of this study was to identify the diversity of mites of this group in tropical flowers, with emphasis on Heliconia species, in Brazil and to determine the fluctuation of the population of these mites in Piracicaba, Sao Paulo state. Specimens from Amazonas, Bahia, Pernambuco, Minas Gerais, Rio de Janeiro, Santa Catarina and São Paulo States were examined. Mites of the genera Asca and Iphidozercon (Ascidae), Cheiroseius and Lasioseius (Blattisociidae), and Proctolaelaps and Tropicoseius (Melicharidae) were collected in flowers of four plant families, with Lasioseius being the most diverse genus. Overall, most specimens found belonged to Tropicoseius, especially Tropicoseius venezuelensis Baker & Yunker; this was the dominant species on five of 13 Heliconia species/hybrids considered in this study. Samples of panicles of Heliconia rostrata Ruiz & Pavón were collected every 2 weeks, in Piracicaba. Six species of those mite families were found, among which Tropicoseius heliconiae Baker & Yunker and T. venezuelensis were the most numerous. The highest population levels of mites of those three families occurred at the beginning and at the end of the year, coinciding with the highest levels of rainfall, relative humidity and temperature, when plant flowers were most numerous and vigorous. Along each panicle, the highest mite densities were found in inflorescences of the three distal eighths of the panicles, where nectar and pollen were probably most abundant.

Asunto(s)

Ácaros y Garrapatas/fisiología , Biodiversidad , Animales , Brasil , Flores , Dinámica Poblacional

RESUMEN

We describe ectoparasite fauna associated with small mammals in fragments of Cerrado biome, central-western Brazil. We analyzed the level of associations and the aggregation patterns according to seasonal and host variations. Small mammals were systematically captured in 54 woodland fragments from February 2012 to July 2013. A total of 1040 animals belonging to eight marsupial and 12 rodent species were sampled; 354 individuals were parasitized by 33 ectoparasite species (twenty five Mesostigmata, seven Phthiraptera and one Siphonaptera). A total of 49 ecological relationships between ectoparasites and small mammals were observed, 24 being new association records. The overall specialization index of all ectoparasites and host species was 0.91 with significant deviation from a random host-parasite association, suggesting a high host-parasite specialization in this system. Specialization indices for ectoparasites ranged from moderate to high, while among host was high, for most species. Contrary to the overall pattern, some ectoparasites had higher prevalence and mean intensity of infestation in the dry season. Overall, ectoparasite prevalence and mean intensity of infestation were not significantly associated with host gender. This study provides significant information about the ectoparasites ecology in relation to specificity, seasonality and hosts gender, contributing to the understanding of host-parasite relationships in Brazilian savannah.

Asunto(s)

Infestaciones por Pulgas/veterinaria , Interacciones Huésped-Parásitos , Infestaciones por Piojos/veterinaria , Marsupiales , Infestaciones por Ácaros/veterinaria , Enfermedades de los Roedores/epidemiología , Ácaros y Garrapatas/fisiología , Animales , Brasil/epidemiología , Femenino , Infestaciones por Pulgas/epidemiología , Infestaciones por Pulgas/parasitología , Pradera , Especificidad del Huésped , Infestaciones por Piojos/epidemiología , Infestaciones por Piojos/parasitología , Masculino , Infestaciones por Ácaros/epidemiología , Infestaciones por Ácaros/parasitología , Phthiraptera/fisiología , Enfermedades de los Roedores/parasitología , Roedores , Siphonaptera/fisiología

RESUMEN

The litchi erineum mite, Aceria litchii (Keifer), is the major pest of litchi, Litchi chinensis Sonnerat (Sapindaceae). This study evaluated the effect of 11 pesticides on the survival of A. litchii as well as on the survival and reproduction of Phytoseius intermedius Evans & McFarlane, the predator most found in association with it in Brazil. The containment of A. litchii in small petri dishes whose bottoms were covered with a solidified paste made of a mixture of gypsum and activated charcoal (9:1 in volume), kept humid, was shown to be adequate for this type of study. For the evaluation of the effect of pesticides on A. litchii, mites leaving the erinia from the pieces of litchi leaves (removed from the plants approximately 24 h earlier) were sprayed under a Potter tower and immediately transferred to the 2.5-cm-diameter petri dishes. After 2, 12, 24, and 48 h of the application, the dishes were examined to evaluate the mite survival. The four pesticides causing the highest levels A. litchii mortality, as well as azadirachtin, were tested for the effect on P. intermedius. For this test, experimental units consisted of discs of uninfested litchi leaves also sprayed under a Potter tower before introducing the predators. Survival and oviposition of the predator were evaluated every 24 h for 5 consecutive days; viability of the eggs laid was also evaluated. Highest mortality of A. litchii occurred with the application of fenpyroximate, sulfur, abamectin, and hexythiazox. Azadirachtin was considered moderately harmful to the predator P. intermedius, whereas other pesticides were classified as harmful. Despite the low efficiency of azadirachtin in the control of the pest, its relative selectivity to P. intermedius would encourage the evaluation on field condition, especially for use in organic production systems.

Asunto(s)

Ácaros y Garrapatas/efectos de los fármacos , Acaricidas/farmacología , Acaricidas/toxicidad , Ácaros y Garrapatas/crecimiento & desarrollo , Ácaros y Garrapatas/fisiología , Animales , Cadena Alimentaria , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/fisiología , Reproducción , Control de Ácaros y Garrapatas

RESUMEN

Acari ectoparasites were collected from bats during 12 months in the Rio Negro farm (19°34'22″S and 56°14'36″W), Aquidauana, Mato Grosso do Sul. A total of 654 bats belonging to the families Phyllostomidae, Noctilionidae, Molossidae, Vespertilionidae and Emballonuridae were captured. Only 136 bats of nine genera and 11 species were parasitised. Periglischrus iheringi Oudemans was the most abundant mite species, and this prevalence may be related to the low degree of host specificity of this species and due to the broad geographical distribution of its hosts. The greatest mean intensity was found to Periglischrus torrealbai Machado-Allison on Phyllostomus discolor Wagner (Phyllostomidae) and Periglischrus tonatii Herrin and Tipton associated with Lophostoma silviculum d'Orbigny (Phyllostomidae), which also had the highest prevalence of infestation.

Asunto(s)

Ácaros y Garrapatas/fisiología , Quirópteros/parasitología , Especificidad del Huésped , Interacciones Huésped-Parásitos , Infestaciones por Ácaros/epidemiología , Infestaciones por Ácaros/parasitología , Animales , Brasil/epidemiología , Quirópteros/clasificación , Ácaros/fisiología , Prevalencia

RESUMEN

Agroecosystems are altered systems whose soil structure has changed affecting the dynamics of soil organisms. This paper aims at evaluation of the effects of garlic farming practices on phenology, richness, abundance, composition and diversity of soil-dwelling Cunaxidae. Ten pilot plots in Guanajuato State were sampled from August 2002 to July 2005, every month, 8 months per year. Ten soil samples (1 kg) were taken from each plot and extracted in Berlese-Tullgren funnels. A total of 108 cunaxids were found, belonging to 11 species. Neocunaxoides andrei was the most abundant, and Cunaxa evansi and Armascirus sp. were least abundant. Relative abundance was highest after harvesting and during plant growth, and lowest during planting. Dactyloscirus nicobarensis and D. candylus were present from planting to harvesting. According to Sörensen's similarity coefficient between cultivation stages, Cunaxidae communities were similar during plant growth and harvesting, sharing 80 % of the species. The highest abundance and diversity were found in 2004, during and after harvesting. Cunaxid species increased over 100 % from planting to the harvesting phase, suggesting that they play an important role in the soil agrosystems food web. Species composition and diversity in cunaxid communities present in garlic crop fields varied with agricultural phase, but little change was observed among the years studied. All species found in this study are new records for the state of Guanajuato and for the garlic crop fields.

Asunto(s)

Ácaros y Garrapatas/clasificación , Ácaros y Garrapatas/fisiología , Agricultura , Biodiversidad , Ajo , Animales , Dinámica Poblacional , Especificidad de la Especie , Factores de Tiempo

RESUMEN

The population dynamics of the three intertidal oribatid species, Alismobates inexpectatus, Fortuynia atlantica and Carinozetes bermudensis, have been studied on the archipelago of Bermuda over the course of a year. All three species are univoltine, showing a clear seasonal demographic pattern, with reproduction from spring to late autumn and a complete standstill of egg production in winter. A seasonal shift in sex ratio could also be observed in all three species and is supposed to be based on sex-dependent mortality. The subtropical climate of Bermuda allows longer reproductive periods than shown in other intertidal or edaphic temperate species and temperature is supposed to be the main factor influencing the demography of these intertidal dwelling mites. Although all three Bermudian species exhibit the same basic seasonal demographic pattern, there are slight temporal shifts in population dynamics, presumably caused by local microclimatic differences among the populations. Larviparity, shown in other littoral oribatid mites, is clearly absent in the present species.

Asunto(s)

Ácaros y Garrapatas/fisiología , Ecosistema , Animales , Bermudas , Femenino , Larva , Masculino , Ninfa , Dinámica Poblacional , Factores de Tiempo

RESUMEN

The family Listropsoralgidae Fain, 1965 (Acariformes: Sarcoptoidea) is represented by the permanent skin ectoparasites associated with the South American and Australian marsupials (12 species) and the South American rodents of the family Echimyidae (1 species). The phylogenetic relationships of these mites (12 ingroup and 2 outgroup species) are reconstructed on the basis of the maximum parsimony (MP) and Bayesian analyses (BA) of 76 morphological characters. MP analysis confirmed monophyly of the listropsoralgid genera, the strict consensus of 18 trees generated by MP has the following pattern: Petauralges (Listropsoralgoides, Didelphialges, Listropsoralges) with poor resolution among species of the genus Listropsoralges. The same tree was generated by BA. Both successive and implied weighting strategies resulted in 7 MP trees: Petauralges (Listropsoralgoides (Didelphialges (Listropsoralges))). The relationships between species of the genus Listropsoralges received the poorest resolution: L. caenolestes (L. monodelphis, L. vossi, L. faini, L. brevisetosa (L. thylamys (L. marmosa-L. caluromys))). The host-parasite relationships of listropsoralgids are briefly discussed. The family Listropsoralgidae is taxonomically revised and to date includes 13 species in 4 genera. Six species and one genus are described as new: Listropsoralges brevisetosus sp. n. from Marmosa murina (Didelphimorphia: Didelphidae) from Peru, Listropsoralges similis sp. n. from Caluromys derbianus (Didelphidae) from Panama, Listropsoralges thylamys sp. n. from Thylamys venustus (Didelphidae) from Bolivia, Listropsoralges vossi sp. n. from Monodelphis domestica (Didelphidae) from Brazil, Listropsoralges caenolestes sp. n. from Caenolestes fuliginosus (Paucituberculata: Caenolestidae) from Ecuador, and Didelphialges metachirus gen. n., sp. n. from Metachirus nudicaudatus (Didelphidae) from Peru. The female of Listropsoralges faini Bochkov and Wauthy, 2009 is described for the first time.

Asunto(s)

Ácaros y Garrapatas/anatomía & histología , Ácaros y Garrapatas/clasificación , Marsupiales/parasitología , Infestaciones por Ácaros/veterinaria , Enfermedades de los Roedores/parasitología , Infestaciones por Garrapatas/veterinaria , Ácaros y Garrapatas/fisiología , Animales , Australia , Femenino , Masculino , Filogenia , Roedores , América del Sur

RESUMEN

The present study reports the occurrence of Parakosa flexipes (Pinichpongse) (Chirodiscidae) for the first time in Brazil, along with its infection sites on Molossus rufus E. Geoffroy. Thirty-eight bats were caught using mist nets that were placed near a house at the Mars Center for Cocoa Science in the state of Bahia, of which 14 (37%) were parasitized by P. flexipes. Parakosa flexipes was observed parasitizing M. rufus on hairs that were evidently longer than others distributed over the bat's body, where up to three parasites could be spotted on a single hair.

Asunto(s)

Ácaros y Garrapatas/fisiología , Quirópteros/parasitología , Animales , Brasil

RESUMEN

Aceria guerreronis Keifer is a major coconut pest in the Americas, Africa and some Asian countries, and occurs in high population levels in northeastern Brazil. The determination of the climatic conditions that favorably affect its population growth and the prevalence and abundance of predatory mites can promote more efficient control practices. Our objective was to evaluate the pattern of occurrence and population dynamics of A. guerreronis, their associated predators and other mites during a 2 year period in a hybrid coconut plantation in the municipality of Una, state of Bahia, northeastern Brazil. Monthly samples of fruits were taken from June 2008 to May 2010 for qualitative and quantitative evaluation of mites. Aceria guerreronis represented 99.9 % of the mites. An average density of 1,117 mites per fruit and a maximum of 23,596 mites per fruit indicated that the level of infestation can be high in Bahia. Bdella ueckermanni Hernandes, Daud and Feres was the most abundant and frequent predator. Population increase of A. guerreronis was directly related to the temperature rise and inversely related to both the increase of air relative humidity and rainfall. The highest population densities occurred from November to March. The largest A. guerreronis populations occurred in fruits with 32 and 48 % of damaged surface. The relationship between prevailing wind direction and incidence of A. guerreronis could not be corroborated or refuted.

Asunto(s)

Ácaros y Garrapatas/fisiología , Cocos , Animales , Brasil , Densidad de Población , Dinámica Poblacional , Conducta Predatoria

RESUMEN

The influence of Calacarus heveae Feres on physiological processes was evaluated in two rubber tree clones. Experiments were conducted in a greenhouse with 5-month-old potted seedlings of RRIM 600 and GT 1 clones, that were either infested with C. heveae or not (non-infested control). The level of photosynthetic pigments, net photosynthetic rate, stomatal conductance, transpiration rate, changes in relative humidity between leaf surface and ambient air (Δw) and intercellular CO(2) concentration (Ci CO(2)) were evaluated. Infested plants showed significant reductions in the rate of transpiration, the rate of photosynthesis, stomatal conductance and Δw. RRIM 600 seedlings showed more pronounced physiological damage than GT 1 seedlings, indicating a lower physiological tolerance of the former clone to the mite. However, carotenoid levels were reduced only in GT 1 seedlings. Photosynthesis was probably reduced due to a decrease in stomatal opening, as indicated by reductions in transpiration rate and stomatal conductance and by the absence of differences in chlorophyll levels between treatments. Our results indicate that populations of C. heveae reduce the productivity of rubber trees. Thus, farmers must to be aware to control this mite pest in rubber tree plantations.

Asunto(s)

Ácaros y Garrapatas/fisiología , Hevea/parasitología , Hojas de la Planta/parasitología , Animales , Fotosíntesis , Hojas de la Planta/fisiología , Estomas de Plantas , Plantones/parasitología , Factores de Tiempo

RESUMEN

Allosathes anitae n. sp. Casanueva & González-Acuña (Astigmata: Crypturoptidae), collected on the Chilean tinamou Nothoprocta perdicaria (Tinamiformes: Tinamidae) from different localities of the Ñuble Province, Chile, is described. Comments on its affinities and differences with Allosathes anepiandrius Gaud, Atyeo & Berla are also included.

Asunto(s)

Ácaros y Garrapatas/anatomía & histología , Ácaros y Garrapatas/clasificación , Aves/parasitología , Plumas/parasitología , Ácaros y Garrapatas/fisiología , Animales , Chile , Femenino , Masculino

RESUMEN

The two spotted spider mite, Tetranychus urticae Koch, is a nontarget herbivore of Bt-cotton, but acquires and accumulates higher levels of Cry toxin than that expressed by transgenic plants. This work investigated the development and reproduction of T. urticae and of the predator Phytoseiulus macropilis Banks, during three successive generations looking for potential nontarget effect. In addition, behavioral studies on feeding preference, oviposition, and predation were carried out on Bt and non-Bt cottons. The development and reproduction of T. urticae and P. macropilis was conducted using leaf discs of Bt and non-Bt cottons. Arena containing leaf discs from both cotton types connected by a slide coverslip were also used in the behavioral studies. Averages of the three generations showed that the Bt-cotton does not affect the development, survival of immature stages, and reproductive output of T. urticae and of the predator P. macropilis. Furthermore, the preference for feeding and oviposition of T. urticae and P. macropilis were similar on both cotton types. In addition, P. macropilis exhibited similar predatory behavior on T. urticae fed on both cotton types. Levels of Cry1Ac toxin in T. urticae was 3.97 times greater than that found in the Bt-cotton plants as determined using a ELISA test. Despite of the amount of toxin acquired by the prey (T. urticae), no detectable levels of Cry1Ac were found in the predatory mite P. macropilis.

Asunto(s)

Ácaros y Garrapatas/fisiología , Gossypium/parasitología , Plantas Modificadas Genéticamente/parasitología , Tetranychidae/fisiología , Animales , Conducta Animal , Gossypium/genética

RESUMEN

The relative effects of host species identity, locality and season on ectoparasite assemblages (relative abundances and species richness) harboured by four cricetid rodent hosts (Akodon azarae, Oligoryzomys flavescens, Oxymycterus rufus and Scapteromys aquaticus) were assessed across six closely located sites in Buenos Aires province, Argentina. Relative abundances of ectoparasites (14 species including gamasid mites, an ixodid tick, a trombiculid mite, lice and fleas), as well as total ectoparasite abundance and species richness, were determined mainly by host species and to a lesser extent by locality (despite the small spatial scale of the study), whereas seasonal effect was weak, albeit significant. The abundances of some ectoparasites were determined solely by host, whereas those of other ectoparasites (sometimes belonging to the same higher taxon) were also affected by locality and/or season. In gamasids, there was a significant effect of locality for some species, but not for others. In fleas and lice, the effect of locality was similar in different species, suggesting that this effect is related to the characteristic life history strategy.

Asunto(s)

Arvicolinae/parasitología , Infestaciones Ectoparasitarias/veterinaria , Ácaros y Garrapatas/fisiología , Animales , Anoplura/fisiología , Argentina , Infestaciones Ectoparasitarias/parasitología , Ratones , Ratas , Estaciones del Año , Siphonaptera/fisiología , Especificidad de la Especie , Humedales

RESUMEN

The two spotted spider mite, Tetranychus urticae Koch, is a nontarget herbivore of Bt-cotton, but acquires and accumulates higher levels of Cry toxin than that expressed by transgenic plants. This work investigated the development and reproduction of T. urticae and of the predator Phytoseiulus macropilis Banks, during three successive generations looking for potential nontarget effect. In addition, behavioral studies on feeding preference, oviposition, and predation were carried out on Bt and non-Bt cottons. The development and reproduction of T. urticae and P. macropilis was conducted using leaf discs of Bt and non-Bt cottons. Arena containing leaf discs from both cotton types connected by a slide coverslip were also used in the behavioral studies. Averages of the three generations showed that the Bt-cotton does not affect the development, survival of immature stages, and reproductive output of T. urticae and of the predator P. macropilis. Furthermore, the preference for feeding and oviposition of T. urticae and P. macropilis were similar on both cotton types. In addition, P. macropilis exhibited similar predatory behavior on T. urticae fed on both cotton types. Levels of Cry1Ac toxin in T. urticae was 3.97 times greater than that found in the Bt-cotton plants as determined using a ELISA test. Despite of the amount of toxin acquired by the prey (T. urticae), no detectable levels of Cry1Ac were found in the predatory mite P. macropilis.

Asunto(s)

Animales , Ácaros y Garrapatas/fisiología , Gossypium/parasitología , Plantas Modificadas Genéticamente/parasitología , Tetranychidae/fisiología , Conducta Animal , Gossypium/genética

RESUMEN

Oligonychus ilicis (McGregor) is among those mite species that can cause damage to coffee plants (Coffea spp.). Species of Phytoseiidae acari are considered the most important and studied predatory mites. The objective of this study was to evaluate the effects of the webbing produced by O.ilicis on its predation by females of the phytoseiids Iphiseiodes zuluagai Denmark & Muma, Euseius citrifolius Denmark & Muma and Amblyseius herbicolus (Chant). Four bioassays were conducted, with three treatments and ten replicates. Each replicate consisted of 25 O.ilicis per experimental unit (a leaf disc of Coffea arabica) according to the tested developmental stage, in independent experiments. To spin the web, 15 adult females were put on each experimental unit for 24h; females were then removed, leaving only the web, and predators and prey to be tested were introduced. Predation was assessed after 24h. In the presence of webbing, the consumption of eggs, larvae and nymphs by I.zuluagai and eggs and larvae by E.citrifolius was lower. For A.herbicolus, egg predation was lower, but larval predation did not vary significantly and predation of nymphs and adults was higher in the presence of webbing. Predators as a whole were more efficient consuming larvae regardless of the presence of webbing. Considering the stages of O.ilicis altogether, webbing reduced the predation potential of I.zuluagai and E. citrifolius, but not of A. herbicolus.

Asunto(s)

Ácaros y Garrapatas/fisiología , Conducta Predatoria , Tetranychidae , Animales , Café/parasitología , Femenino