Showing papers in "Neotropical Entomology in 2009"
TL;DR: The traps baited with feces were the most efficient in capturing dung beetles, and the forest was the phytophysiognomy with the highest diversity and abundance, which indicates that plant-covering influences the structure of the dung beetle community.
Abstract: The spatial changes in species composition are closely related to the environmental aspects associated to habitat variation. The natural landscapes of Minas Gerais are organized in mosaics, associated to anthropic action or natural factors. Here we study dung beetles in the Perdizes Plateau, Carrancas (Minas Gerais, Southeastern Brazil). The area of study has a landscape composed mainly by four phytophysiognomies: Brazilian savannah, altitudinal grasslands, rupestrian fields and forests. The objective of our study was to detect the spatial distribution in composition of dung beetles and estimate beta diversity between phytophysiognomies. The dung beetles were collected in four areas of each phytophysiognomy, using pitfall traps baited with carrion or human feces. A total of 2,363 individuals of 52 species were collected: 1,247 individuals of 29 species at the forest, 20 exclusive to this phytophysiognomy; 352 individuals of 17 species at the grassland, with four exclusive species; 386 individuals of 19 species at the Brazilian savannah, with five exclusive species; and 378 individuals of 20 species at the rupestrian field, with five exclusive species. The traps baited with feces were the most efficient in capturing dung beetles, and the forest was the phytophysiognomy with the highest diversity and abundance. This pattern indicates that plant-covering influences the structure of the dung beetle community. High beta diversity indicates that phytophysiognomies are complementary. However, the other phytophysiognomies are also important for conservation, once species composition occurring at each environment is essential for the maintenance of the regional diversity.
78 citations
TL;DR: The aim of this brief text is to instigate young researchers to initiate more elaborated field work, including experimental manipulations in multitrophic systems, to explore in an interactive way the structure that maintain preserved viable communities in the Neotropical savanna.
Abstract: The causal mechanisms shaping and structuring ecological communities are among the most important themes in ecology. The study of insect-plant interactions in trophic nets is pointed out as basic to improve our knowledge on this issue. The cerrado tropical savanna, although extremely diverse, distributed in more than 20% of the Brazilian territory and filled up with rich examples of multitrophic interactions, is underexplored in terms of biodiversity interaction. Here, this ecosystem is suggested as valuable to the study of insect-plant interactions whose understanding can throw a new light at the ecological communities' theory. Three distinct systems: extrafloral nectary plants or trophobiont herbivores and the associated ant fauna; floral herbivores-predators-pollinators; and plants-forest engineers and associated fauna, will serve as examples to illustrate promising new pathways in cerrado. The aim of this brief text is to instigate young researchers, mainly entomologists, to initiate more elaborated field work, including experimental manipulations in multitrophic systems, to explore in an interactive way the structure that maintain preserved viable communities in the Neotropical savanna.
78 citations
TL;DR: Larvae of 13 blowfly species from Colombia are described and an illustrated key for all them is presented.
Abstract: Larvae of 13 blowfly species from Colombia are described and an illustrated key for all them is presented. All larval instars of Calliphora nigribasis Macquart, Cochliomyia macellaria (Fabricius), Chrysomya albiceps (Wiedemann), Chrysomya megacephala (Fabricius), Hemilucilia segmentaria (Fabricius), Hemilucilia semidiaphana (Rondani), Lucilia eximia (Weidemann) are described, but the second and third instars of Compsomyiops verena (Walter), and only the third instar of Calliphora vicina Robineau-Desvoidy, Cochliomyia hominivorax (Coquerel), Lucilia peruviana Robineau-Desvoidy, Lucilia sericata (Meigen) and Sarconesiopsis magellanica (Le Guillou).
62 citations
TL;DR: The use of the DNA barcode has been discussed by those applying successfully this approach to identify and diagnose species and by those who believe that the flaws in the use of this molecular marker are as many as to negate the worth of its employment as mentioned in this paper.
Abstract: Faced by a growing need of identification and delimitation of new and established cryptic species that are being lost at an increasing rate, taxonomists can now more than ever take advantage of an enormous variety of new molecular and computational tools. At this moment they should be open to all new available technologies in the so called "technology-driven revolution" in systematics. The use of the "DNA barcode" has been discussed by those applying successfully this approach to identify and diagnose species and by those who believe that the flaws in the use of this molecular marker are as many as to negate the worth of its employment. For insects of the order Lepidoptera neither side seems totally correct orwrong, and although many groups of lepidopterans have been taxonomically resolved by using exclusively or additionally this marker for diagnoses, for others the "barcode" helped little to resolve taxonomic issues. Here we briefly present some pros and cons of using DNA barcode as a tool in taxonomic studies, with special attention to studies with groups of Lepidoptera developed in the last few years.
58 citations
TL;DR: Increase of diversity of Pronophilina with altitude is marginally related to higher limited resource availability, and the lower pressure of predators and parasites at higher elevation can contribute with higher abundance, but cannot be directly correlated with higher diversity.
Abstract: Samplings of Pronophilina, a species-rich group of neotropical montane butterflies, were carried out along an elevational transect in Ecuador to assess the effect of altitude on their distribution patterns, diversity and community structure. All diversity indices were significantly correlated with altitude. Maximum diversity expressed in species-richness, Shannon index and Fisher alpha was recorded at 2600 m. Two assemblages of species were identified in the lower (below 2100 m) and upper (above 2300 m) sections of the transect by means of correspondence (CA) and cluster analysis. A comparison of Sorensen similarity coefficients showed lower values, thus higher turnover in the intermediate elevational band. Several closely related morphologically and ecologically species were found to have mutually exclusive altitudinal distribution patterns. A comparison with similar studies in Venezuela, Colombia and Peru revealed far reaching congruency of the patterns of altitudinal diversity of Pronophilina in distant areas of the Andes. In particular, the Shannon index reaches its maximum values at 2600-2850 m, which invariably correspond to ca. 400-500 m below the upper limit of cloud forest. Increase of diversity of Pronophilina with altitude is marginally related to higher limited resource availability. The lower pressure of predators and parasites at higher elevation can contribute with higher abundance, but cannot be directly correlated with higher diversity. Higher diversity is related with intrisic characteristics of the group, such as aggregated diversity by overlapping of elevational faunal assemblages and higher speciation ratio towards high elevations, particularly near timberline.
55 citations
TL;DR: Available data indicate a strategy of pheromonal parsimony in the chemistry communication of these insects, i.e., the same compound is sometimes secreted by different glands, different species and for different functions.
Abstract: The semiochemicals produced by termites have been little studied compared to those of ants and bees. Among the limiting factors are the cryptic habits of termites, together with the difficulty in maintaining many species in the laboratory. The semiochemicals of Isoptera include trail, sex and alarm pheromones and a complex mixture of substances responsible for the recognition of nestmates. Although little is known about the semiochemicals of termites, available data indicate a strategy of pheromonal parsimony in the chemistry communication of these insects, i.e., the same compound is sometimes secreted by different glands, different species and for different functions.
49 citations
TL;DR: In this paper, a study aimed to analyze the social wasps species diversity in a cerrado vegetation at the west region of the State of Bahia, where 19 species of wasps were found, with Chartergus globiventris de Saussure, Chartergellus communis Richards and Metapolybia cingulata (Fabricius).
Abstract: This study aimed to analyze the social wasps species diversity in a cerrado vegetation at the west region of the State of Bahia. Nineteen species of social wasps were found, with Chartergus globiventris de Saussure, Chartergellus communis Richards and Metapolybia cingulata (Fabricius) being recorded for the first time for the State of Bahia. The arboreous cerrado showed a higher species richness (S = 19) and diversity (H' = 2,33) than the agroecossistems (farms) (S = 8; H' = 1,84). However, nest abundance was higher at the agroecossystems (N = 107 nests) than at the arboreous cerrado (N = 87 nests). The physiognomy of "cerrado campo sujo" showed the lowest abundance of social wasps colonies (N = 61 nests) and intermediate values of species richness (S = 13) and diversity (H' = 2,20).
49 citations
TL;DR: This analysis indicated higher sample heterogeneity in the secondary forest, with two clusters of species, while in the pine plantation the species belong to a single cluster, and applied the ant mosaic hypothesis to explain the distribution of the leaf-litter fauna and spatial autocorrelation tests among samples.
Abstract: We investigated the influence of Pinus afforestation on the structure of leaf-litter ant communities in the southeastern Brazilian Atlantic Forest, studying an old secondary forest and a nearly 30 year-old never managed Pinus elliottii reforested area A total of 12,826 individual ants distributed among 95 species and 32 genera were obtained from 50 1 m(2) samples/ habitat Of these, 60 species were recorded in the pine plantation and 82 in the area of Atlantic forest; almost 50% of the species found in the secondary forest area were also present in the pine plantation The number of species per sample was significantly higher in the secondary forest than in the pine plantation Forest-adapted taxa are the most responsible for ant species richness differences between areas, and the pine plantation is richer in species classified as soil or litter omnivorous-dominants The specialized ant predators registered in the pine plantation, as seven Dacetini, two Basiceros, two Attini and two Discothyrea, belong to widely distributed species The NMDS (non-metric multidimensional scaling) ordination also suggested strong differences in similarity among samples of the two areas Furthermore, this analysis indicated higher sample heterogeneity in the secondary forest, with two clusters of species, while in the pine plantation the species belong to a single cluster We applied the ant mosaic hypothesis to explain the distribution of the leaf-litter fauna and spatial autocorrelation tests among samples We argue that the results are likely related to differences in quality and distribution of the leaf-litter between the pine plantation and the secondary area
46 citations
TL;DR: Considering the higher parasitism rate, shorter biological cycle, higher survival and sex ratio, T. pretiosum strain RV is the most appropriated to be used in field releases aiming at P. includens control.
Abstract: This research aimed to point out the most suitable trichogrammatid strains to control the soybean looper Pseudoplusia includes Walker. Biological parameters and parasitism ratio of 11 Trichogramma pretiosum Riley, one Trichogramma atopovirilia Oatman & Platner and one Trichogrammatoidea annulata De Santis strains reared on P. includens eggs were evaluated. Among all tested strains/species, T. pretiosum strain RV, collected in Rio Verde, GO, had the fastest development cycle and the highest percentage of parasitism of P. includens eggs. There was no difference in the parasitism and in the number of parasitoid emerged per egg among the tested parasitoid species and strains. Accordingly to the cluster analysis, T. pretiosum strain RV reared on P. includens eggs had the best performance. Considering the higher parasitism rate, shorter biological cycle, higher survival and sex ratio, T. pretiosum strain RV is the most appropriated to be used in field releases aiming at P. includens control.
46 citations
TL;DR: Diferencas na temperatura, umidade e precipitacao pluviometrica parecem ter sido os principais responsaveis pelas diferencias nos tempos de decomposicao entre os dois periodos do ano.
Abstract: Carrion breeding insects may be of great utility in crimes briefing. Studies on forensic entomology are restricted to few localities in Brazil and very few of them were done in the cerrado vegetation (a type of Savannah) until now. This work aimed to survey the main species of dipterans associated with the decomposition process of Sus scrofa and the insect succession pattern in carcasses in the Cerrado. The study was carried out in the dry and humid season of the year, in two cerrado vegetation profiles in Uberlândia, MG. Two pig carcasses were placed in each vegetation profile and time period of the year. The decomposition process was slower and insects were more abundant in the dry season. Differences in temperature, air humidity and pluvial precipitation seemed to be the main physical factors responsible for the differences in the time of decomposition of the pig carcasses between the two seasons. Fourteen species of dipterans (59,467 specimens) bred in the decomposing carcasses. Chrysomya albiceps (Wiedemann) was the species more abundantly breed in the two periods. The other species that breed in the carcasses were: C. putoria (Wiedemann), Hemilucilia segmentaria(Fabricius), Lucilia eximia(Wiedemann) (Calliphoridae), Peckia (Pattonella) intermutans(Walker), Peckia (Squamatoides) trivitatta(Curran), Sarcodexia lambens(Wiedemann) (Sarcophagidae), Musca domestica(L.), Ophyra aenescens(Wiedemann), Stomoxys calcitransL. (Muscidae), Fannia pusio(Wiedemann), Fannia sp. (Fanniidae), Hermetia illuscens L. (Stratiomyidae) and Phoridae sp. The Cerrado of this region presents many dipterans potential forensic indicators.
44 citations
TL;DR: Evaluating the genetic variability in pesticide susceptibility in populations of Bemisia tabaci collected from different Brazilian agricultural regions through the use of two different tests showed significant differences in the susceptibility to the pesticides among B. tabaci populations.
Abstract: Monitoring the susceptibility of a pest population to pesticides is essential for resistance management programs. The objective of this research was to evaluate the genetic variability in pesticide susceptibility in populations of Bemisia tabaci (Gennadius) collected from different Brazilian agricultural regions through the use of two different tests. Four whitefly populations, two from Goias state (GO-1 and GO-2) e two from Bahia state (BA-1 and BA-2), were tested against a susceptible reference one (SusIAC). A residual contact bioassay was used to evaluate the pesticide susceptibility of each population by using diagnostic concentration bioassays and by estimating the baseline susceptibility data to each one of the tested insecticides, acetamiprid, imidacloprid, thiamethoxam, chlorpyrifos and endosulfan. Adult insects of unknown age and sex were tested. Evaluations were performed after 24h for endosulfan and 48 h for the other chemicals. Both procedures showed significant differences in the susceptibility to the pesticides among B. tabaci populations. However, the discrimination among B. tabaci populations was more evident with the use of diagnosis tests. The population GO-2 was significantly less susceptible to the tested pesticides than SusIAC, mainly to neonicotinoids. The most critical resistance situation of B. tabaci was detected to thiamethoxam, followed by imidacloprid.
Abstract: Forensic entomology uses biological and ecological aspects of necrophagous insects to help in criminal investigations to estimate the post-mortem interval (PMI) or to determine the cause of death Recent papers demonstrated that the presence of toxins in decomposing tissues may alter the insect developmental rate of insects exploiting such tissues as food Thus, preliminary tests with artificial diets in laboratory are necessary to create a database to investigate and quantify the modifications that can occur with the collected insects from a criminal scene, avoiding any errors on the PMI estimates The present study aimed to evaluate the developmental rate of Chrysomya albiceps (Wiedemann) reared on: a) artificial diets containing animal tissues: bovine liver (D1), raw muscle (D2), stomach (D3), and chicken heart (D4); b) artificial diet without animal tissue (D5); and c) a control group (C), which had only meat The efficiency of each substrate was assessed by immature weight gain (mg), larval developmental time, larval and pupal survival, emergence interval and adult size D1 to D4 diets did not restrict C albiceps development; however, larvae reared on D1 and D2 diets presented a lower adult emergence rate D3 and control group showed similarities regarding the efficiency parameters (rate and emergence interval) Thus, the use of diet D3, artificial diet with stomach, is the most recommended
TL;DR: This study analyzes the combination between host-parasitoid models and the concept of economic threshold level on a spatio-temporal scale and concludes that spatial structure is essential for models of this nature.
Abstract: Ecological modeling is an important tool for investigating dynamic behavior patterns in populations, trophic interactions, and behavioral ecology. However, the ecological patterns that reflect population oscillation trends are often not clearly visible without analytical instruments such as ecological models. Thus, ecological modeling plays a fundamental role in describing demographic processes that are important for population dynamics. Ecological models, besides making possible the visualization of ecological patterns, may also reveal patterns of population persistence in many trophic systems, including prey-predator or host-parasitoid relationships, interactions that are commonly present in integrated pest management programs. In this forum, we present the main ecological aspects important for model building and implementation of integrated pest management programs for insects. Particularly, in this study, we analyze the combination between host-parasitoid models and the concept of economic threshold level on a spatio-temporal scale. As a conclusion about the model combination, spatial structure is essential for models of this nature, since its introduction into the system significantly alters the economic threshold-level values.
TL;DR: In this article, the composition of euglossine bees in three lowland rainforest habitats of Peru, a primary old forest, a reforested and managed forest, and a very disturbed forest were reported.
Abstract: Euglossine bee males are easily lured to chemical baits imitating natural fragrances gathered by bees, providing a widely applied measure for estimating the diversity and abundance of euglossines. In here, I report the composition of euglossine bees in three lowland rainforest habitats of Peru, a primary old forest, a reforested and managed forest, and a very disturbed forest. A total of 2,072 males of euglossine were collected, belonging to 33 species and four genera. Although a comparable diversity relative to other studies from the Amazonian region was found, no significant differences among the sampled areas were detected. Perhaps, the short time and low intensity surveys here used (< 3 months) were not good enough indicators of forest disturbance without additional data. Compared to other major studies on the euglossine bee fauna, Loreto is most similar to the species assemblage reported from lowland rainforest in Brazil (Manaus), central Peru (Panguana) and southern Peru (Tambopata).
TL;DR: In this article, two bioassays were conducted to evaluate the suitability of host plants of fall armyworm (FAW), Spodoptera frugiperda (J E Smith), in the Brazilian agro-ecosystem.
Abstract: Two bioassays were conducted to evaluate the suitability of host plants of fall armyworm (FAW), Spodoptera frugiperda (J E Smith), in the Brazilian agro-ecosystem. Larval development and survival were analyzed by infesting leaves of maize, grain sorghum, Johnson grass, soybean, Brachiaria and tobacco with FAW newly hatched larvae in a no choice test. No significant differences of survival were observed among insects reared on different hosts, except for tobacco, where no survivors were recorded. Larvae fed on soybean and artificial diet grew larger than those fed on the other hosts. The heaviest pupa was observed from larva fed on artificial diet and the lighter from larva fed on Brachiaria grass. No significant differences were reported on larval development time on natural hosts, but it was longer for larvae reared on artificial diet. Three classes of larval development time were observed on maize, four on sorghum, Brachiaria and soybean, and five on artificial diet. Nearly 85% of FAW larvae completed development within 12 d on mayze; 77% on grain sorghum, 80% on Johnson grass, 68% on Brachiaria and 83% on soybean within 14 d and 69% on artificial diet within 17 d. The host suitability to FAW decreases from maize to sorghum, soybean and Brachiaria.
TL;DR: 16 parental strains of Bombyx mori L from the germplasm banks of the Universidade Estadual de Maringá--UEM, and Associação dos Criadores de Bicho-da-Seda de Nova Esperança e Regiões Sericícolas do Paraná--ACESP were evaluated regarding biological and productive traits economically important.
Abstract: The classification and characterization of silkworm strains are important for sericulture, which is supported by the constant development of new hybrids. In this study, 16 parental strains of Bombyx mori L from the germplasm banks of the Universidade Estadual de Maringa - UEM, and Associacao dos Criadores de Bicho-da-Seda de Nova Esperanca e Regioes Sericicolas do Parana - ACESP, were evaluated regarding biological and productive traits economically important. The Chinese C122-B and C121-A, and the Japanese HA-A and HA-B strains yielded the highest cocoon weight, which is related to the raw silk percentage. Our data will be useful in breeding programs for the production of superior silkworm strains and hybrids.
TL;DR: No entanto, o desenvolvimento de tecnicas de criacao eficientes desse inimigo natural e inicialmente necessario para that ele possa ser utilizado em programas de controle biologico de P. elaeisis nos avaliamos a idade mais suscetivel do hospedeiro e os efeitos da idade do parasitoide.
Abstract: Palmistichus elaeisis Delvare & LaSalle e um parasitoide pupal natural de pupas de lepidopteros desfolhadores de eucalipto e e considerado um promissor agente de controle biologico. No entanto, o desenvolvimento de tecnicas de criacao eficientes desse inimigo natural e inicialmente necessario para que ele possa ser utilizado em programas de controle biologico. Pupas de Bombyx mori L. sao hospedeiras alternativas em potencial para criacao massal de P. elaeisis. Por isto, nos avaliamos a idade mais suscetivel do hospedeiro e os efeitos da idade do parasitoide na producao de progenie de P. elaeisis. Pupas de B. mori com 24, 48, 72 ou 96h de idade foram expostas a femeas de P. elaeisis de mesmas idades. A duracao do ciclo de vida (ovo-adulto) de P. elaeisis nao foi afetada pela idade das femeas, entretanto, a idade do hospedeiro afetou o desenvolvimento do parasitoide. O melhor parasitismo foi obtido com femeas do parasitoide com 72h a 96h e pupas de B. mori com 48h a 72h de idade, que permitiram a elevacao da progenie de P. elaeisis.
TL;DR: Anopheles (K.) cruzii is the probable vector for malaria transmission inside or near the Atlantic Forest fragments, but the role of other species cannot be ignored, as 53% of the sampled anophelines belonged to the subgenus Nyssorhynchus.
Abstract: Autochthonous malaria cases in the state of Espirito Santo, Brazil, are distributed in mountainous regions surrounded by the Atlantic Forest. While some aspects of this disease are unclear, detection of possible vector species can help to elucidate epidemiological uncertainties. Entomological and natural infection studies were carried out using anophelines (Diptera: Culicidae) captured in the municipality of Santa Tereza, ES. Monthly captures were made from March 2004 to February 2006. CDC-CO2 traps were used from dusk (6:00 P.M.) to dawn (6:00 A.M.) to capture anophelines in the following habitats: near the houses, in open areas (at ground level) and inside, and at the margins of the forest (canopy and ground level). Shannon light traps were also used at the same locations of the CDC-CO2 traps. A total of 2,290 anophelines within 10 species were captured. The relative frequency of Anopheles (Kerteszia) cruzii Dyar & Knab / A.(K.) homunculus Komp was the highest, with the majority captured in CDC-CO2 traps installed in the forest canopy. The main species captured in Shannon traps was A.(Nyssorhynchus) strodei Root. The largest number of anophelines was captured from July to September and from 6:00 P.M. to 10:00 P.M. Anopheles (K.) cruzii is the probable vector for malaria transmission inside or near the Atlantic Forest fragments, but the role of other species cannot be ignored, as 53% of the sampled anophelines belonged to the subgenus Nyssorhynchus. The natural infection of A. cruzii, A. parvus (Chagas) and A. galvaoi Causey, Deane & Deane by Plasmodium vivax detected by PCR from DNA extracted from their thoraxes supports this view.
TL;DR: This paper summarizes the control strategies adopted so far, especially the methods and efficiency of the entomological components of leishmaniasis control programs, and indicates areas for study that should be encouraged and developed since they show promising results.
Abstract: Phlebotomines are of medical and veterinary concern as they vector leishmaniasis, bartonellosis and some arboviruses. The adaptations of some species to places modified by humans bring these vectors into contact with dwellings, which can facilitate disease transmission, and the vector control strategies adopted have rendered controversial results. Regarding leishmaniasis, for instance, which vector and reservoirs control can be effective, there is an assumption that the incidence of human infection is directly related to the number of infectious dogs, as well as to entomological factors. Therefore, vector control can provide a cheaper and more practical solution to prevent cases of leishmaniasis. Nevertheless, due to the complexity of the factors involved, chemical control is still essential, and biological insecticides and insecticide plants, for example, represent areas for study that should be encouraged and developed since they show promising results. This paper summarizes the control strategies adopted so far, especially the methods and efficiency of the entomological components of leishmaniasis control programs.
TL;DR: P Surveys of euglossine bees by attracting males to scent baits showed that species of the Atlantic Rainforest like Euglossa imperialis Cockerel, E. truncata Moure and Eulaema cingulata Fabricius occur in the gallery forest of the Sao Francisco river under the semi-arid climate of the caatinga region.
Abstract: Euglossini are typical bees of Neotropical rainforests and only a few species occur in the Caatinga. The Sao Francisco river, which is the only permanent river in the semi-arid NE-Brazil, is bordered by a gallery forest with evergreen leaves. This environment offers flooral rewards along the year. Surveys of euglossine bees by attracting males to scent baits showed that species of the Atlantic Rainforest like Euglossa imperialis Cockerel, E. truncata Moure and Eulaema cingulata Fabricius occur in the gallery forest of the Sao Francisco river under the semi-arid climate of the caatinga region. These bees are restricted to the gallery forests which function as bio-corridors, and are absent at places where the forests were cut down. This emphasizes the need to protect the threatened gallery forests to maintain biodiversity.
TL;DR: Results indicate that neem (Neemseto), at the concentrations studied, may be effective to control S. frugiperda because it promotes meaningful morphological alterations in the mesenteron.
Abstract: Research involving plants with insecticide activity evolved significantly in the last decades. Among these plants, the neem tree, Azadirachta indica, is commonly used against several insects, mainly Lepidoptera. The neem efficiency depends on the target insect and on the concentration used. A barrier against potential toxic agents ingested together with the food is the alimentary canal. Thus, this research aimed to describe the histology of the alimentary canal of Spodoptera frugiperda (J E Smith) larvae fed on leaves treated with neem (Neemseto®) at a concentration of 0.5% and 1.0% and non treated, at different intervals (48, 96, 144, 192 and 240h), by quantifying the regenerative cells and analyzing the secretion of the mesenteron histochemically. Larvae were immobilized at low temperatures (-4oC), the alimentary canal was removed, fixed in Bouin´s aqueous, embedded in paraplast and historesin, sectioned and stained with hematoxilin-eosin and periodic acid- Schiff. The histology of the alimentary canal of S. frugiperda was similar to other lepidopterans. Neem effects on morphology were seen only in the mesenteron, depending on the time and concentration used, such as: epithelium, reduction on regenerative cells and on the secretory activity in this region, confirmed by the histochemistry in both neem concentrations. These alterations were observed after 96h at 1.0%, and 144h at 0.5%. These results indicte that neem (Neemseto®), at the concentrations studied, may be effective to control S. frugiperda because it promotes meaningful morphological alterations in the mesenteron.
TL;DR: The aim of this study was to isolate and identify the fungi associated with Culicidae larvae found in different habitats, such as fruit shells, rock holes, lakes, aquatic plants, palm bracts and ceramic pots, in several municipalities of Brazilian Amazonia.
Abstract: Several species of the family Culicidae are important vectors of diseases in humans and other animals. Immature stages are filter-feeders of organic particulate matter and microorganisms. Studies on microbial diversity can contribute to the discovery of new substances that can be used in the pharmaceutical industry for food or for biological control. The aim of this study was to isolate and identify the fungi associated with Culicidae larvae found in different habitats (natural and artificial), such as fruit shells, rock holes, lakes, aquatic plants, palm bracts and ceramic pots, in several municipalities of Brazilian Amazonia, especially in the states of Amazonas and Rondonia. A total of 38 fungal lineages were isolated from larvae of Aedes aegypti (L.), Aedes fluviatilis (Lutz), Trichoprosopon digitatum (Rondani), Anopheles argyritarsis argyritarsis Robineau-Desvoidy, Anopheles darlingi Root, Aedeomyia squamipennis (Lynch Arribalzaga), Mansonia titillans (Walker) and Uranotaenia sp. The following fungi occurred associated with the larvae of Culicidae: Acremonium kiliense, Aspergillus sydowii, Fusarium sacchari var. sacchari, Fusarium merismoides var. merismoides, Gliocladium viride, Paecilomyces sp., Penicillium citrinum, Penicillium sclerotiorum, Penicillium melinii and Penicillium oxalicum. Macro- and microscopic characteristics of the lineages are presented, as well as information on their geographical distribution.
TL;DR: In this article, an alternative method for the capture of neotropical social wasps is described, which may supplement or replace the procedures commonly used in wasp surveys, such as Malaise traps, bottle traps and meat baits.
Abstract: In this work, an alternative method for the capture of neotropical social wasps is described, which may supplement or replace the procedures commonly used in wasp surveys. The method was tested in a seasonal semideciduous forest in the northwest of Sao Paulo State, collecting a larger number of species and a greater abundance of social wasps and of other Hymenoptera than other methods also used in the same area, namely Malaise traps, bottle traps and meat baits. The proposed method was adapted from Wille (1962) who used an attractive solution based on water and honey for bee attraction. In here, the attractive solution was based on water, salt and crystal sugar, and was effective in attracting bees and solitary wasps, but mainly social wasps, which is the group of interest for this report.
TL;DR: In this article, the life history parameters of the greenhouse whitefly Trialeurodes vaporariorum (Westwood), an important pest of bean crops in Colombia, were determined in environmental control chambers on two dry bean (Phaseolus vulgaris) cultivars (cv.).
Abstract: Life-history parameters of the greenhouse whitefly Trialeurodes vaporariorum (Westwood), an important pest of bean crops in Colombia, were determined in environmental control chambers on two dry bean (Phaseolus vulgaris) cultivars (cv.). Trialeurodes vaporariorum longevity on cv. Chocho decreased as temperature increased from 22.6 d at 19oC to 5.9 d at 26oC. Fecundity was significantly lower at 19oC (8.6 eggs/female), as compared to 22oC (32.6 eggs/female) and 26oC (33.3 eggs/female) on cv. Chocho. Fecundity on cv. ICA-Pijao was much higher (127.2 eggs/female) than on cv. Chocho (32.6 eggs/female) at 19oC. The intrinsic rate of population increase (rm) was highest at 22oC (0.061), intermediate at 19oC (0.044) and lowest at 26oC (0.035) on cv. Chocho, and was 0.072 on cv. ICA-Pijao at 19oC. Life history parameters of T. vaporariorum are compared to those of one of its natural enemies, the parasitoid Amitus fuscipennis MacGown & Nebeker. Finally, data are presented on the distribution of the parasitoid related to the altitude for the Valle del Cauca, Colombia.
TL;DR: Liogenys suturalis Blanchard took the whole year to complete its life cycle, developing through three different instars, and the highest larval feeding activity and development occurred in February and June, and adult flight activities were between the second fortnight of September and December.
Abstract: Liogenys suturalis Blanchard is one of the main soil pests associated to corn, wheat and oat crops in the Southern Mato Grosso do Sul State. This work aimed to investigate the bioecological and behavioral aspects of this pest. The study was carried out in several municipalities of Mato Grosso do Sul State under field and laboratory conditions from August 2004 to December 2006. In the laboratory, we studied the incubation period and egg viability, the number of instars, and pupal and adult sex-related traits. The insect distribution was determined yearly, as well as the period of insect flying and some behavioral aspects during mating. Egg viability averaged 81.7%, with an incubation period of 22.8 ± 4.32 days. Liogenys suturalis took the whole year to complete its life cycle, developing through three different instars. The highest larval feeding activity and development occurred in February and June, and adult flight activities were between the second fortnight of September and December. Sex dimorphism was observed in both pupae and adults. Flights were concentrated from 7:00 to 8:00 PM. The average time for mating was 9.82 min. The observed adult sex ratio was 0.63.
TL;DR: The study revealed the possibility of developing the oil from sugar apple seeds, an agricultural waste, into a broad spectrum product friendly to the environment and human health for crop pest management.
Abstract: Development of alternative methods for pest management is needed with the increased concern for adverse effects of pesticides for human health and the environment. The main goal of our study was to test the oil from seeds of sugar apple (Annona squamosa), an edible tropical fruit for pest control. The oil pressed out of seeds was as effective in controlling the silverleaf whitefly, Bemisia argentifolii Bellows & Perring (Homoptera: Aleyrodidae), infesting leaves of tomato plants in greenhouse conditions as the recommended insecticide, with the advantage of not being phytotoxic. When observed with a scanning electron microscope, the seed oil caused whitefly nymphs to shrink and detach from the leaf surface. Sugar apple seed oil was also very effective in controlling the cotton aphid, Aphis gossypii Glover (Homoptera: Aphididae), on melon leaves and the Kanzawa spider mite, Tetranychus kanzawai Kishida (Acari: Tetranychidae), on soybean leaves. The study revealed the possibility of developing the oil from sugar apple seeds, an agricultural waste, into a broad spectrum product friendly to the environment and human health for crop pest management.
TL;DR: This study reports the first records of the parasitism rates of the association among ectoparasitic flies of the family Streblidae found in phyllostomid bats in the state of Maranhão.
Abstract: This study reports the first records of the parasitism rates of the association among ectoparasitic flies of the family Streblidae found in phyllostomid bats in the state of Maranhao. Specimens were collected in patches of secondary forest and borders of mangrove in the village of Quebra Pote, located in the south portion of the island of Sao Luis. A total of 201 flies of 15 species and eight genera [Aspidoptera falcata Wenzel, A. phyllostomatis (Perty), Mastoptera minuta Costa Lima, Megistopoda aranea (Coquillett), M. proxima (Seguy), Speiseria ambigua Kessel, Stizostrebla longirotris Jobling, Strebla guajiro (Garcia & Casal), S. hertigi Wenzel, Trichobioides perspicillatus (Pessoa & Galvao), Trichobius costalimai Guimaraes, T. dugesii Townsend, T. dugesioides phyllostomus Guerrero, T. joblingi Wenzel and T. longipes (Rudow)] were collected from 50 individuals of nine species of phyllostomid bats [Artibeus lituratus (Olfers), A. obscurus Schinz, Carollia perspicillata L., Glossophaga soricina Pallas, Lophostoma carrikeri J A Allen, Micronycteris minuta Gervais, Phyllostomus discolor Wagner, P.hastatus Pallas and Sturnira lilium E Geoffroy)]. Mastoptera minuta, T. costalimai, T. longipes, A. falcata and S. longirostris, were the most frequently found ectoparasites, present in at least 50% of the infected bats. Two species of bats, C. perspicillata e P. discolor, showed the highest richness of ectoparasites, with four species of flies each, and an infection rate of 46% and 100%, respectively.
TL;DR: Abiotic factors such as altitude, temperature and humidity cannot explain observed variation in community structure across sites, indicating other variables such as vegetation cover, density of the vegetation and soil type may play a role in the community structure of these insects.
Abstract: The community structure of dung beetles in the middle and lower river basin of the Gaira river, Sierra Nevada de Santa Marta, Colombia, is described. Four sites were selected along an altitudinal gradient of 50-940 m for sampling from June to October, 2004. Dung beetles were captured using modified pitfall traps and manual recollections. We captured 7,872 individuals belonging to 29 species, distributed in 15 genera and five tribes of Scarabaeinae. Canthon and Onthophagus were the most diverse genera, each represented by six species. The sampled sites shared the following species: Onthophagus acuminatus Harold, O. clypeatus Blanchard, O. marginicollis Harold. Bocatoma was the most diverse site with 23 species; whereas Port Mosquito presented the highest abundance, with 3,262 individuals. Seven species represented 89% of all captures: Canthidium sp., Dichotomius sp., Uroxys sp. 1, Uroxys sp. 2, O. marginicollis, O. clypeatus and O. acuminatus. Of the 29 captured species, 17 belonged to the functional group of diggers and 10 were ball-rollers. We did not observe significant among-site differences in community structure. Abiotic factors such as altitude, temperature and humidity cannot explain observed variation in community structure across sites, indicating other variables such as vegetation cover, density of the vegetation and soil type may play a role in the community structure of these insects.
TL;DR: In this paper, the authors carried out a study to characterize fruit fly populations on an organic guava orchard (Psidium guajava cv. Paluma) in the municipality of Una, southern region of the state of Bahia, Brazil, using faunistic analysis of the adult fruit fly specimens captured in McPhail traps from January 2004 through March 2007.
Abstract: We carried out a study to characterize fruit fly populations on an organic guava orchard (Psidium guajava cv. Paluma) in the municipality of Una, southern region of the state of Bahia, Brazil, using faunistic analysis of the adult fruit fly specimens captured in McPhail traps from January 2004 through March 2007. A total of 22,673 specimens of Anastrepha (15,306 females and 7,367 males) were captured. Thirteen species of Anastrepha were recorded. A. fraterculus and A. obliqua were the more frequent and dominant species, accounting for 90.1% of all females captured in the traps. A. fraterculus was the predominant species (more frequent, constant and dominant). The high value of the Simpson index (0.62) and the low values of Shannon-Wiener (0.83) and equitability (0.49) indices indicated the dominance and high frequency of A. fraterculus and A. obliqua on the guava orchard despite the presence of other fruit species as potential hosts of fruit flies.
TL;DR: In this paper, the alimentary canal histology of S. frugiperda larvae fed on leaves treated with neem (Neemseto) at a concentration of 0.5% and 1.0% at different intervals (48, 96, 144, 192 and 240 h).
Abstract: Research involving plants with insecticide activity evolved significantly in the last decades. Among these plants, the neem tree, Azadirachta indica, is commonly used against several insects, mainly Lepidoptera. The neem efficiency depends on the target insect and on the concentration used. A barrier against potential toxic agents ingested together with the food is the alimentary canal. Thus, this research aimed to describe the histology of the alimentary canal of Spodoptera frugiperda (J E Smith) larvae fed on leaves treated with neem (Neemseto) at a concentration of 0.5% and 1.0% and non treated, at different intervals (48, 96, 144, 192 and 240 h), by quantifying the regenerative cells and analyzing the secretion of the mesenteron histochemically. Larvae were immobilized at low temperatures (-4 degrees C), the alimentary canal was removed, fixed in Bouin s aqueous, embedded in paraplast and historesin, sectioned and stained with hematoxilin-eosin and periodic acid- Schiff. The histology of the alimentary canal of S. frugiperda was similar to other lepidopterans. Neem effects on morphology were seen only in the mesenteron, depending on the time and concentration used, such as: epithelium, reduction on regenerative cells and on the secretory activity in this region, confirmed by the histochemistry in both neem concentrations. These alterations were observed after 96 h at 1.0%, and 144 h at 0.5%. These results indicate that neem (Neemseto), at the concentrations studied, may be effective to control S. frugiperda because it promotes meaningful morphological alterations in the mesenteron.