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Post-fire recovery of arthropod assemblage in an area of Brazilian savanna Texte intégral
2020
Hélida Ferreira da Cunha | Werther Pereira Ramalho | Amanda Martins Dias | Brenda Romeiro Peixoto | Gabriel Sampaio Jesus | Jennifer de Paula Oliveira | Thamara Missel Pereira da Silva
Fire is a frequent agent of disturbance in tropical savannas (e.g., Brazilian Cerrado), but relatively few studies have analyzed how the arthropod community responds to fire disturbance. Following the incursion of an accidental fire into a Cerrado fragment in Central Brazil, we investigated whether the arthropod community is structured by abiotic (climate or fire) or biotic (succession) factors. Our study commenced one week after fire and during the six months afterward. We found 22 arthropod orders, of which Diptera, Hymenoptera, Hemiptera, Blattaria and Coleoptera were the most representative. More than 40% of the arthropod abundance was recorded 40 days after the fire event. The overall arthropod abundance and richness fluctuated in the six months following the fire and does not seem to be related to climatic variables. Temporal beta diversity was explained by a reduction in richness differences along the intervals of time, but the community recovery needs to be treated with caution. The increase in replacement in the last intervals in relation to the fire event indicates that biotic interactions may occur with the arrival of late colonizers and suggest that arthropod communities need a long time to be restructured. These results indicate that the processes of restructuring of the arthropod communities after human-induced fire events are temporally complex, involving loss, gain and taxon replacement, but long-term studies are still needed to understand the dynamics of communities.
Afficher plus [+] Moins [-]Infestation of Magulacra nigripennata Dognin (Lepidoptera: Cossidae) in a commercial cupuassu plantation in Nova Califórnia, Rondônia State, Brazil Texte intégral
2020
Rodrigo Souza Santos | Tadário Kamel de Oliveira | Giordano Bruno da Silva Oliveira | Taysa Faltz Macedo
The cupuassu (Theobroma grandiflorum (Willd ex Sprengel) K. Schum.) is a native tree from the tropical rainforest and one of the most important fruit trees in the Amazon region. Its pulp and seeds are widely used in the alimentary industry, as well as food by the people of northern Brazil. Among the factors that can compromise the production of cupuassu are the attack of diseases and insect pests. The aim of this work is to report the attack of a wood-borer lepidopteran in commercial cupuassu plantation located in the district of Nova Califórnia, Rondônia State, Brazil. In April 2019 an infestation of a wood-borer insect was observed causing the death of branches. Branches containing caterpillars in their inside were collected and taken to the Entomology Laboratory of the Embrapa Acre, where they were placed in a screened cage. After about 60 days, an adult insect emerged, which was identified as Magulacra nigripennata, a lepidopteran associated with cocoa and cupuassu plantations in that country. A random survey of 100 plants in the plantation area detected an infestation level of 36%, indicating the harmful potential of this pest to the cupuassu crops in the Amazon region.
Afficher plus [+] Moins [-]Entomological profile and new registers of the genera Anopheles (Diptera, Culicidae) in a Brazilian rural community of the District of Coxipó do Ouro, Cuiabá, Mato Grosso Texte intégral
2020
Adaiane Catarina Marcondes Jacobina | Jozeilton Dantas Bandeira | Fábio Alexandre Leal dos Santos | Elisangela Santana de Oliveira Dantas | Diniz Pereira Leite-Jr
The order Diptera is constituted of insects that possess numerous varieties of habitats, these winged, commonly called mosquitoes, comprise a monophyletic group. Malaria transmitters in Brazil are represented by mosquitoes of the Anopheles genus, being it principal vector species Anopheles (Nyssorhynchus) darlingi Root. Collectings were accomplished in the rural area of Cuiabá in the region of Coxipó do Ouro/MT, and a total 4,773 adult mosquitoes of the genus Anopheles were obtained. The prevailing species in the collectings where An. (Nys.) darlingi with 3,905 (81.8%), considered the vector of major epidemiological expression in the region, followed by Anopheles (Nyssorhynchus) argyritarsis (Robineau-Desvoidy) 267 (5.6%) and Anopheles (Nyssorhynchus) triannulatus (Neiva & Pinto) 226 (4.7%). This report might be useful to entomological surveillance, demonstrating that the Coxipó do Ouro/MT locality might be elected as an area to be monitored, once the presence of such vector in this type of environment indicates a potential malaria transmission risk for the neighbouring regions in the state of Mato Grosso.
Afficher plus [+] Moins [-]Selectivity and sublethal effect of botanical extracts on adults of Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) Texte intégral
2020
Joanina Gladenucci | José Carlos de Almeida Pernambuco Filho | Regiane Cristina de Oliveira Freitas Bueno | Filipe Pereira Giardini Bonfim
The objective was to assess the selectivity and sublethal effect of botanical extracts on adults of Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae). Plant species used: Rosmarinus officinalis L., Mikania glomerata Spreng., Varronia curassavica Jacq., Chenopodium ambrosioides L., Vermonia polyanthes Spreng., Plectranthus amboinicus Spreng., Tetradenia riparia Codd., Artemisia absinthium L., Cymbopogon citratus Stapf. Plant material were reared in laboratory and leaves collected during the morning were used to prepare the extracts as following: 100 g of leaves from each plant were macerated and immersed in 300 mL of triple-extracted methyl alcohol and evaporated on rotavapor. Then, 250 mg of crude extract was diluted in 1000 mL of water. The experimental design for selectivity was done in randomized blocks with five repetitions, following a standardized protocol of the International Organization for Biological Control (IOBC) and accordingly classified. In sublethal effect, the design was completely randomized with twenty repetitions, where the eggs exposed to parasitism were sprayed with the treatments. In both experiments the control was twofold (water and chlorpyrifos). Regarding selectivity, the botanical extracts of M. glomerata, C. ambrosioides, V. polyanthes, P. amboinicus, A. absinthium and C. citratus were classified as slightly harmful (class 2), chlorpyrifos as moderately harmful (class 3). In the evaluation of sublethal effects, the botanical extracts of C. ambrosioides and C. citratus initially presented reduced number of parasitized eggs, reduction in total parasitized eggs and female longevity. It can be concluded that C. citratus botanical extract has small selectivity and causes sublethal effects on T. pretiosum adults.
Afficher plus [+] Moins [-]Sources of resistance to black aphid in cowpea varieties used as green grains Texte intégral
2020
Vinicius Borges | Daniel Rodrigues Nere | Leandro Carvalho da Silva | Marília Gomes Caminha | Ervino Bleicher | Cândida Hermínia Campos de Magalhães Bertini
Evaluation of resistance of Vigna unguiculata L. landraces, used as green beans, to Aphis craccivora Koch was tested. Eleven landraces and standard genotypes were used in a free choice protocol: BR 17-Gurguéia, VITA 7 (susceptible), BRS Guariba and TVu 408P2 (resistant). A completely randomized blocks design was used with six replicates. Seedlings were infested with five six-day-old adult insects. The number of alive adults after 48 h and of alive nymphs after 96 h was evaluated. The results evidenced that there are high genetic diversity among the landraces, the antibiosis as the main mechanism of resistance. By means of multivariate analysis we suggest crosses among the commercial cultivar BRS Guariba and the most dissimilar varieties CCE-088, CCE-075, CCE-013 and CCE-062 to obtain superior hybrids.
Afficher plus [+] Moins [-]Survey of the Heteroptera (Hemiptera) on pastures from Espírito Santo state, Brazil: new records, range extension, and notes of potential pests Texte intégral
2020
Mayra Vélez | Lívia Aguiar Coelho | David dos Santos Martins | Paulo Sergio Fiuza Ferreira
Espírito Santo is a Brazilian state that has a wide variety of habitats, providing a high biological diversity of fauna and flora. However, few reports had been shown about the insect diversity of this region, especially of heteropterans insects that inhabit on pasture ecosystems. In the present study, forty-three species of Heteroptera belonging to thirteen families were collected on pastures on Espírito Santo state, Brazil: Alydidae (1 sp.), Berytidae (3 sp.), Blissidae (1 sp.), Coreidae (7 sp.), Miridae (16 sp.), Nabidae (1sp.), Pentatomidae (3 sp.), Pyrrhocoridae (1 sp.), Reduviidae (6 sp.), Rhopalidae (1 sp.), Rhyparochromidae (1sp.), Thaumastocoridae (1 sp.) and Tingidae (1 sp). Among the species; Cebrenis tenebrosa (Brailovsky, 1995) is recorded for the first time in Brazil. The range extension is also included for several heteropterans collected on the Espírito Santo state. The following species: Blissus aff. antillus (Leonard, 1968); Collaria oleosa (Distant, 1883); Oebalus ypsilongriseus (De Geer, 1773), and Trigonotylus tenuis (Reuter, 1893) were observed causing damages on pastures, therefore, in this study, we suggested those species as potential pastures pests. This study aims to increase the knowledge about the heteropterans and to show the presence of some pest species that may cause serious damage to pastures and consequently affect the economy of cattle breeders on the state.
Afficher plus [+] Moins [-]Strains of Spodoptera frugiperda (J.E.Smith) (Noctuidae) in the states of Paraná and São Paulo, Brazil Texte intégral
2020
Francielly Silveira Richardt | Adriana Micheli | Daniele Tasior | Elderson Ruthes | Luís Amilton Foerster
Two strains of Spodoptera frugiperda (J.E. Smith) were first described in the United States; in Brazil, in the states of Rio Grande do Sul, Mato Grosso, and western Paraná they have also been reported. This study was aimed at identifying these strains in Norte Pioneiro and Campos Gerais, in the states of Paraná and southwestern São Paulo. Larvae of S. frugiperda were collected in the cities of Ponta Grossa, Tibagi, Arapoti, and Wenceslau Braz in Paraná, and in the city of Itaberá, in São Paulo. PCR-RFLP genotyping of the COI gene was carried out using sixty-six specimens. Based on their electrophoretic pattern, 51 individuals were identified as corn strain, five as rice strain, and 10 as hybrids (Rice in MspI and Maize in SacI). Our findings indicate that both S. frugiperda strains are present the study areas.
Afficher plus [+] Moins [-]Infestation indices and characterization of injuries of Drosophila suzukii Matsumura (Diptera: Drosophilidae) in Barbados cherry Texte intégral
2020
Léo Rodrigo Ferreira Louzeiro | Miguel Francisco Souza-Filho | Adalton Raga | Carla A. Bulgarelli | Louis Bernard Klaczko
Females of Drosophila suzukii Matsumura (Diptera: Drosophilidae) have a serrated ovipositor that causes severe physical damage to soft fruit. This behaviour results in the early ripening and accelerated rotting of infested fruit. In addition, feeding by larvae softens of the fruit peel, causing in a depreciation in commercial value. In this study, results of infestation indices, pupal viability, egg-adult period, degradation time of infested fruit, and description of physical injuries caused by oviposition and larval feeding of D. suzukii in Barbados cherries (Malpighia emarginata DC., Malpighiaceae) are described. Overall, our results and discussion contribute to the understanding of the status of D. suzukii as an insect pest of the Barbados cherry.
Afficher plus [+] Moins [-]Influence of seasonality on macroinvertebrate diversity associated with the aquatic fern Salvinia biloba Raddi Texte intégral
2020
Rennan Leite Martins Coutinho | Isabella Rodrigues Lancellotti | Arthur Ribeiro Flores | Marcelo Guerra Santos
Abstract. The genus Salvinia is composed of fast-growing floating ferns, capable of surviving in different environmental conditions. Some authors suggest that the relationships between this genus and macroinvertebrates may serve as water quality indicators. The present study aimed to determine the influence of seasonality and water quality on macroinvertebrate diversity associated with the Salvinia biloba Raddi. Water and fern were collected in rainy and dry seasons and was conducted a microbiological analysis of the water, as well as, the area of fern cover on the water, richness, and density of macroinvertebrates. Microbiological analysis of the water detected > 5,700 CFU/mL (rainy season) and 175 CFU/mL (dry season) of heterotrophic bacteria and was positive for total thermotolerant coliforms. The S. biloba cover on the water surface was 100% in the rainy and 30% in the dry season. In the rainy season, 142 macroinvertebrates were identified, divided into 12 morphospecies, with a density of 434 individuals/m3. In the dry season, there were 419 individuals in 14 morphospecies, with a density of 2,076 individuals/m3 exhibited. The highest species density recorded in the rainy season was for Chironomidae sp.1 (Diptera) (57.71%) and Odonata Zygoptera sp.1 (17.44%), and in the dry season, Chironomidae sp.2 (73.98%) followed by Gerromorpha sp.1 (Hemiptera), with 9.54%. The Sørensen similarity index between the two seasons was 53.84%. The higher density of Gerromorpha sp.1 in the dry season may indicate an increase in environmental integrity.
Afficher plus [+] Moins [-]Description of nymphs and ontogenetic morphometry of Triatoma ryckmani Zeledón & Ponce, 1972 (Hemiptera: Heteroptera: Reduviidae: Triatominae) Texte intégral
2020
Dayse da Silva Rocha | Carolina Dale | João Aristeu da Rosa | Cleber Galvão
Triatoma ryckmani Zeledón & Ponce, 1972 is a species found in sylvatic habitat at Central America. Considered rare in the past and poorly studied, nowadays can be found inside houses with potential of dispersal and colonization. All five instars of T. ryckmani are described based on optical and scanning electron microscopy. The postembryonic development of the head analyzed by ontogenetic morphometry showed the largest changes occur in the first three instars. Information about morphology of the immature stages of disease vectors can be helpful in the identification process increasing speed and efficiency of control strategies.
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