Ocorrência de Trichospilus diatraeae (Hym.: Eulophidae) em broca-das-cucurbitáceas, no Brasil

Este trabalho tem como objetivo registrar a primeira ocorrência, no Brasil, do parasitóide de pupas Trichospilus diatraeae (Cherian & Margabandhu, 1942) (Hymenoptera: Eulophidae) na broca-das-cucurbitáceas, Diaphania hyalinata (L.) (Lepidoptera: Pyralidae). A espécie T. diatraeae já foi relatada no Brasil em pragas da gravioleira no Distrito Federal e eucalipto nos estados de Minas Gerais e São Paulo. No sistema produtivo da abóbora D. hyalinata é reconhecidamente uma praga importante por causar sérios prejuízos em função das injúrias provocadas em diferentes partes da planta. A ocorrência do parasitóide foi registrada em pupas coletadas no campo, localizado no campus experimental do Centro de Ciências Agrárias da Universidade Federal do Espírito Santo (UFES), no município de Alegre-ES.

Movement of Heterorhabditis amazonensis and Steinernema arenarium in search of corn fall armyworm larvae in artificial conditions

Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) is considered to be the main pest of maize crops in Brazil. Entomopathogenic nematodes (EPN) may be used to control this pest and exhibit different, unique abilities to search for their hosts. The movement of EPN in relation to S. frugiperda was evaluated. To test for horizontal movement, a styrofoam enclosure filled with sand was divided into segments, nematodes were placed at the entrance to the enclosure and a larva was placed at the end of each division. The same approach was used to evaluate vertical movement; however, PVC pipes were used in this case. In general, the mortality was inversely proportional to the initial distance between host and nematodes. In the vertical displacement test, both nematodes were able to kill the larvae up to a distance of 25 cm. Therefore, the infective juveniles of H. amazonensis and S. arenarium can search out, infect and kill larvae of S. frugiperda at distances of up to 60 cm and 25 cm of horizontal and vertical displacement, respectively.

Parasitismo em lagarta-do-cartucho, Spodoptera frugiperda (Smith), na região do Triângulo Mineiro, MG

Com o objetivo de avaliar a freqüência e distribuição de parasitóides associados a larvas da lagarta do cartucho, Spodoptera frugiperda (Smith), foram realizadas amostragens em campos comerciais da cultura do milho (Zea mays), nos anos agrícolas 1991/92 (duas regiões) e 1992/93 (cinco regiões). em cada local amostrado foram coletadas aproximadamente 100 larvas, em plantas com 20 a 40 dias após a emergência. As larvas foram criadas em laboratório a 25 ± 2ºC, UR 50 - 60%, fotoperíodo de 14 horas e observadas diariamente. Os parasitóides mais freqüentes foram: Chelonus texanus (Cresson) (Hymenoptera: Braconidae), Diadegma sp. (Hymenoptera: Ichneumonidae) e Archytas incertus (Macquart) (Diptera: Tachinidae). Foi observado que o parasitismo total foi de 10,3% em 1991/92 e 13,8% em 1992/93. Os parasitóides Diptera apresentaram preferência pela fase de pupa da lagarta do cartucho (76,5%), nos dois anos agrícolas. Os parasitóides Hymenoptera tiveram preferência por larvas de 3º e 4º ínstares (41,9 e 45,2%), no ano agrícola 1991/92 e de 2º e 3º ínstares (39,1 e 43,5%), no ano agrícola 1992/93.

Acidentes por lepidópteros (larvas e adultos de mariposas): estudo dos aspectos epidemiológicos, clínicos e terapêuticos

Os autores apresentam e discutem aspectos dos acidentes causados por larvas de lepidópteros (mariposas), enfatizando as manifestações dermatológicas e a dor intensa que caracterizam estes agravos. Além disso, são apresentadas larvas de mariposas que causam manifestações extracutâneas, tais como severos distúrbios de coagulação e artropatias anquilosantes, e ainda dermatites provocadas por insetos adultos. Os principais grupos de lepidópteros causadores de acidentes em humanos são demonstrados, e as medidas terapêuticas atualizadas são discutidas. O lepidopterismo e o erucismo são acidentes comuns, e é importante que o dermatologista saiba reconhecer e tratar esse tipo de envenenamento.

Descrição de um surto de lepidopterismo (dermatite associada ao contato com mariposas) entre marinheiros, ocorrido em Salvador, Estado da Bahia

A ocorrência uma dermatite pápulo-pruriginosa em toda a tripulação de um navio comercial filipino em Salvador, BA, foi associada ao contato com mariposas do gênero Hylesia. Esta enfermidade insólita é causada por cerdas corporais das mariposas (flechettes). O relato dos casos serve como alerta para possíveis situações semelhantes.

Protandry and female size-fecundity variation in the tropical butterfly Brassolis sophorae

Protandry (the emergence of males before fe males) is currently explained either as a mating strategy to maximize number of matings in the males, or a way to minimize pre-reproductive mortality in females, Models of protandry have generally ignored variation in female quality (reproductive potential). We recorded the sex ratio, female body mass, wing length and potential fecundity (number and mass of eggs) of the tropical butterfly Brassolis sophorae through the emergence period. Temporal variation in female size and fecundity correlated with male potential for acquiring mates. Females from the end of the emergence period showed lower fecundity and size. Males emerging before and close to the median date of the female emergence period had greater mating opportunities. Males emerging either very early or late were penalized by few mating opportunities, or by encounters with small: low-quality females, respectively.

Toxicity of extracts and isobutyl amides from Piper tuberculatum: potent compounds with potential for the control of the velvetbean caterpillar, Anticarsia gemmatalis

The isobutyl amides pellitorine (compound 1) and 4,5-dihydropiperlonguminine (compound 2) were extracted from the seeds of Piper tuberculatum Jacq. (Piperaceae) in yields of 6.10 and 4.45% respectively. The acute toxicities to the velvetbean caterpillar, Anticarsia gemmatalis (Hubner) (Lepidoptera: Noctuidae), of extracts of seeds, leaves and stems of P. tuberculatum, and of compounds 1 and 2, were evaluated by means of contact bioassays. The extracts caused 80% mortality when doses higher than 800.00 mu g insect(-1) of extract of seeds, leaves and stems were administered to the velvetbean caterpillars. Compounds I and 2 showed 100% mortality at doses of 200 and 700 mu g insect(-1) respectively. The LD50 and LD90 values were respectively 31.3 and 104.5 mu g insect(-1) for compound 1, and 122.3 and 381.0 mu g insect(-1) for compound 2. The potential value of extracts and amides derived from P. tuberculatum as efficient insecticides against velvetbean caterpillars is discussed. (c) 2007 Society of Chemical Industry.

Oviposition of a leaf-miner on Erythroxylum tortuosum (Erythroxylaceae) leaves: hierarchical variation of physical leaf traits

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

New Neotropical species of Ceraeochrysa Adams (Neuroptera: Chrysopidae)

Species of Ceraeochrysa Adams are distributed from southeast Canada to Argentina. Larvae feed on aphids, thrips, white flies, mites, and neonatal larvae of Lepidoptera in varied agroecosystems. Seven species are known in Venezuela, viz. Ceraeochrysa achillea Freitas & Penny, C. angulata (Navas), C. bitacornua Freitas & Penny, C. caligata (Banks), C. cubana (Hagen), C. everes (Banks), and C. valida (Banks). In this study, three species are described as new to science, Ceraeochrysa melaenopareia sp. nov., Ceraeochrysa pittieri sp. nov., and Ceraeochrysa torresi sp. nov.

Effect of the insect growth regulator diflubenzuron on the predator Podisus nigrispinus (Heteroptera: Pentatomidae)

Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) is a common natural predator of defoliating caterpillars in agricultural and forest systems. Insecticides acting as growth regulators of insect pests can indirectly affect their predators through consumption of contaminated prey. We examined the reproductive performance of P. nigrispinus fed on caterpillars of Anticarsia gemmatalis Hubner (Lepidoptera: Noctuidae) reared on soybean leaves exposed to the chitin synthesis inhibitor, diflubenzuron. Caterpillars of A. gemmatalis were fed for 12 h with treated soybean leaves and offered to adults of the predator P. nigrispinus over five consecutive days. The fertility of P. nigrispinus was reduced when feeding on diflubenzuron treated caterpillars, especially at the beginning of the reproductive period, but recovered 3 weeks later. The effects of diflubenzuron ingestion on the life table parameters of P. nigrispinus included an increase in the period taken to double the population size, and reductions in the intrinsic rate of population increase, generation duration, and net reproductive rate. Diflubenzuron therefore had an indirect negative effect on the reproduction and the population dynamics of the non-target predator P. nigrispinus. Clearly, its use in integrated pest management requires further evaluation.

Relationship between predation by Podisus nigrispinus and developmental phase and density of its prey, Plutella xylostella

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A Meta-Analysis of Predation Risk Effects on Pollinator Behaviour

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Wasmannia spp. (Hym., Formicidae) and insect damages to cocoa in Brazilian farms

Diagnostic insect damage to cocoa tree leaves and fruits were compared in situations with and without the presence of the little fire ants, Wasmannia auropunctata and the closely related and sympatric W. cf rochai. No significant differences in thrips, lepidopteran, or chrysomelid beetle damage to fruits, or to young and old leaves, were associated with these ants. However, significant increases of pseudococcids Planococcus citrii, associated with areas dominated by W. auropunctata, and to a lesser degree with W. cf rochai, were present. W. auropunctata has been reported to be a canopy mosaic dominant in cocoa farms, but the lack of reduced herbivore incidences and its lack of spatial permanence do not support favoring its populations for the management of phytophagous insect control.

The fish fauna in tropical rivers: The case of the Sorocaba river basin, São Paulo, Brazil

A survey was carried out on the fish species in the Sorocaba River basin, the main tributary of the left margin of the Tietê River, located in the State of São Paulo, Brazil. The species were collected with gill nets. After identification of the specimens, their relative abundance, weight and standard length were determined. Up to the present moment there are not any studies that focus this subject in this hydrographic basin. Fifty-three species, distributed in eighteen families and six orders were collected. Characiformes were represented by twenty-eight species, Siluriformes by seventeen species, the Gymnotiformes by three species, Perciformes and Cyprinodontiformes by two species, and the Synbranchiformes by one species. Among the collected species there were two exotic. The most abundant species were Astyanax fasciatus and Hypostomus ancistroides. In relation to total weight the most representative species were Hoplias malabaricus and Hypostomus ancistroides. Cyprinus carpio, Prochilodus lineatus, Schizodon nasutus and Hoplias malabaricus were the most representative species in relation to average weight. Largest standard length were recorded for Sternopygus macrurus, Steindachnerina insculpta, Eigenmannia off. virescens and Cyprinus carpio.

Spatial pattern of parasitism in Diatraea saccharalis Fab. (Lep., Crambidae) populations at two different spatial scales in sugarcane fields in Brazil

The biological control of Diatraea saccharalis is regarded as one of the best examples of successful classical biological control in Brazil. Since the introduction of the exotic parasitoid, Cotesia flavipes, the decrease in D. saccharalis infestation in sugarcane fields has been attributed to the effectiveness of this agent. Native Tachinidae fly parasitoids (Lydella minense and Paratheresia claripalpis) have also been implicated in the success. Quantitative data confirming the actual contribution of these agents to the control of D. saccharalis are, however, rather scant. The purpose of this study was to investigate the spatial pattern of parasitism of these parasitoids in D. saccharalis populations at two large spatial scales (fields and zones). To investigate this subject, a large data set comprising information collected from a sugarcane mill located in the state of São Paulo, Brazil (São João sugarcane mill) was analysed. When regressions between the proportion parasitism against host density were computed, the percentage of significant regressions with either a positive or a negative slope was very small at both spatial scales for both parasitoid species. Regressing the densities of tachinid-parasitized hosts against host densities per field showed that these parasitoids presented a 'moderate aggregative' response to host densities, as 53.33% of the regressions were positively significant. Cotesia flavipes was 'weakly aggregated' on host densities at the field level, because only 33.33% of the regressions were positively significant. At the zone level, neither aggregative nor spatial proportion parasitism responses were evident for either parasitoid species due to the small percentage of significant regressions computed.