529 resultados para Flea beetles.


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O estudo das palmeiras nativas é importante por seu grande valor econômico e na manutenção das comunidades de várias espécies de vertebrados e invertebrados que se alimentam de seus frutos, sementes e folhas. A eficiência na produção dos frutos das palmeiras está diretamente relacionada com a presença de insetos polinizadores, principalmente besouros, abelhas e moscas. A palmeira Mauritia flexuosa, comumente conhecida como buriti, é a espécie mais abundante do Brasil e é também chamada de “árvore da vida”, por ser 100% utilizável. Este trabalho teve como objetivo contribuir para o conhecimento da ecologia da polinização do buriti em ambiente de restinga, no município de Barreirinhas, Maranhão, Brasil. Para tanto, obteve-se dados sobre fenologia reprodutiva, biologia floral, sistema reprodutivo e visitantes florais. Para o acompanhamento fenológico foram selecionados 25 indivíduos de cada sexo, os quais foram observados de agosto/2009 a outubro/2012. As fenofases de floração e frutificação foram relacionadas com as variáveis climáticas através de correlação de Spearman. O processo de abertura e longevidade floral foi acompanhado durante o pico de floração da espécie, verificando-se a viabilidade polínica, a receptividade estigmática, as regiões emissoras de odor e a ocorrência de termogênese. Para determinar o sistema reprodutivo foram feitos testes de polinização cruzada e apomixia. O transporte de grãos de pólen pelo vento foi observado, por meio de lâminas de vidros untadas com vaselina que permaneceram penduradas próximas às inflorescências pistiladas durante 24 horas. Os visitantes florais foram coletados através do ensacamento de 20 inflorescências de cada sexo, sendo classificados de acordo com a frequência e o comportamento. O buriti apresentou padrão fenológico anual, sincrônico e sazonal, com floração de agosto a novembro e pico de queda dos frutos em setembro, o que corresponde à estação seca, diferindo do observado na Amazônia, onde estes eventos fenológicos ocorreram na estação chuvosa. Esta diferença pode ser justificada pela grande disponibilidade de água na região, o que faz com que o buriti não necessariamente dependa das chuvas para florescer. Este fato foi evidenciado pela correlação significativa negativa das fenofases com a precipitação e com a umidade relativa. A forte incidência solar e a disponibilidade de água no ambiente contribuíram para o sucesso na floração e frutificação do buriti. Além disto, fatores bióticos podem ter exercido influência no comportamento fenológico, cuja estratégia reprodutiva adotada parece ser a sincronização da floração e da frutificação com a atividade dos polinizadores e dispersores. Dessa maneira a espécie garante a sua reprodução em um período ótimo para a germinação de sementes e estabelecimento de plântulas. O sistema reprodutivo do buriti é xenogâmico. O conjunto de características florais, aliado à abundância de pólen e ao forte odor leva a crer que essa palmeira tenha como principal estratégia de polinização a cantarofilia, porém o vento também possui grande importância na polinização. Além de apresentar polinização do tipo misto (ambofilia), as flores do buriti atraíram uma grande variedade de visitantes, cuja riqueza foi maior que a observada na Amazônia.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This work aimed to evaluate the repellent and deterrent effect of the application of concentrations of neem and chinaberry oil on bean leaves on the leaf beetles Diabrotica speciosa (Germar) and Cerotoma arcuata (Olivier). The concentrations of neem oil tested were 0.625, 1.25, 2.50, 5.00, 10.00 and 20,00 mL, corresponding respectively to 1, 2, 4, 8, 17 and 33 ppm of azadirachtin A and the concentrations of chinaberry oil used were the same used to neem oil, corresponding, however, to 1.875, 3.75, 7.50, 15.00, 30.00 and 60.00 mg mL(-1) of chinaberry extract, respectively. For the free-choice tests, glass containers were used as arenas, whereas for the no-choice tests Petri dishes were used, where in both one insect per treatment was released in the center. Attractiveness was evaluated in predetermined time periods, in addition to the leaf consumption, at the end of the experiment. Neem oil is repellent to D. speciosa and C. arcuata, with more efficient results at the 5.00, 10.00 and 20.00 mL concentrations. All concentrations of neem oil reduce leaf consumption of both insects, except in the no-choice test with D. speciosa, in which only the 10.00 and 20.00 mL concentrations are deterrent. Chinaberry oil provides high repellent activity on both leaf beetle species, and the 10.00 and 20.00 mL concentrations stood out. The 10.00 and 20.00 mL concentrations of chinaberry oil are deterrent to D. speciosa and C. arcuata.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Seed dispersal effectiveness (SDE) is a conceptual framework that aims at quantifying the contribution of seed dispersal vectors to plant fitness. While it is well recognized that diplochorous dispersal systems, characterized by two successive dispersal steps performed by two different vectors (Phase I=primary seed dispersal and Phase II=secondary seed dispersal) which are common in temperate and tropical regions, little attention has been given to distinguishing the relative contribution of one-phase and two-phase dispersal to overall SDE. This conceptual gap probably results from the lack of a clear methodology to include Phase II dispersal into the calculation of SDE and to quantify its relative contribution. We propose a method to evaluate the relative contribution of one-phase and two-phase dispersal to SDE and determine whether two seed dispersers are better than one. To do so, we used the SDE landscape and an extension of the SDE landscape, the Phase II effect landscape, which measures the direction and magnitude of the Phase II dispersal effect on overall SDE. We used simulated and empirical data from a diplochorous dispersal system in the Peruvian Amazon to illustrate this new approach. Our approach provides the relative contribution of one-phase SDE (SDE1) and two-phase SDE (SDE2) to overall SDE and quantifies how much SDE changes with the addition of Phase II dispersal. Considering that the seed dispersal process is context dependent so that Phase II depends on Phase I, we predict the possible range of variation of SDE according to the variation of the probability of Phase II dispersal. In our specific study system composed of two primate species as primary dispersal vectors and different species of dung beetles as secondary dispersal vectors, the relative contribution of SDE1 and SDE2 to overall SDE varied between plant species. We discuss the context dependency of the Phase II dispersal and the potential applications of our approach. This extension to the conceptual framework of SDE enables quantitative evaluation of the effect of Phase II dispersal on plant fitness and can be easily adapted to other biotic and/or abiotic diplochorous dispersal systems.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The flight periodicity of western balsam bark beetle (Dryocoetes confusus Swaine) in Big Cottonwood Canyon, Utah, was studied during the summer months of 1992, 1993, and 1994. Contents of baited funnel traps were tallied by species up to 3 times weekly. Two main periods of flight activity were observed each year. The first and, generally, largest occurred in early summer soon after flight was initiated for the season. A 2nd period was observed in late summer, generally August. Timing of the 2 periods was influenced by unusually warm or cool weather in each study year. The 1st period had more males than females while the 2nd period had a majority of females. Except during periods of cool or wet weather, western balsam bark beetles were found to be active at least at minimal levels from June through September.

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As with many organisms across the globe, Cicindela nevadica lincolniana is threatened with extinction. Understanding ecological factors that contribute to extinction vulnerability and what methods aid in the recovery of those species is essential in developing successful conservation programs. Here we examine behavioral mechanisms for niche partitioning along with improving techniques for captive rearing protocol and increasing public awareness about the conservation of this local insect. Ovipositional selectivity was examined for Cicindela nevadica lincolniana, Cicindela circumpicta, Cicindela togata, Cicindela punctulata, and Cicindela fulgida. Models reflect that these species of co-occurring tiger beetles select different ranges of salinity in which to oviposit thereby reducing the potential for interspecific competition. In a second study, thermoregulatory niche partitioning was examined for the same complex of tiger beetle species. Time spent in the sun, on different substrates, and engaging in various behaviors associated with thermoregulation were significantly different during different parts of the day and between species. I continued along a previous line of study to develop a viable captive rearing program. So far fourteen adult Cicindela nevadica lincolniana have been successfully reared in captivity. Overwintering mortality has been determined as a key factor in the mortality of this species in captivity. Finally, I examined the potential for using the visual arts to promote the conservation of Cicindela nevadica lincolniana and associated saline wetlands. The results from surveys conducted at the exhibit suggest that art exhibits can have a strong positive impact on members of the community.

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Karyotypes are defined for two nearctic species of marmots, Marmota olympus (2n = 40) and M. vancouverensis (2n = 42), and supplemental information is included on the karyotypes of M. flaviventris, M. monax ochracea, and M. marmota. The six North American species of Marmota (NF = 66) comprise a distinct group as compared with the middle Asian species (NF = 70) for which the karyotypes are known. Karyologic findings and zoogeographic evidence based upon the distribution of two nearctic species of host-specific cestodes indicate that M. broweri, in northern Alaska, is a pre-Würm relict. Its affinities appear to be with the North American caligata-group rather than with the northeastern Siberian M. camtschatica. The occurrence on M. broweri of the Asian flea, Oropsylla silantiewi, has not been explained. Some ecological and behavioral characteristics of M. broweri are briefly described and compared with those of other species. Family groups of M. broweri hibernate together in single winter dens that are plugged at the entrance; copulation takes place before the animals emerge from the winter den, near mid-May; face-glands are utilized in marking of territory. French abstract: Les auteurs définissent les caryotypes de deux espèces néarctiques de marmottes, Marmota olympus (2n=40) et M. vancouverensis (2n=42), et donnent des précisions sur les caryotypes de M. flaviventris, M. monax ochracea et M. marmota. Les six especes de Marmota (NF=66) d'Amérique du Nord forment un groupe distinct des espèces d'Asie centrale (NF=70) dont Ie caryotype est connu. Les données caryologiques et les preuves zoogéographiques basées sur la répartition de deux espèces néarctiques de cestodes spécifiques de I'hôte démontrent que M. broweri, dans l'Alaska septentrional, est une relicte du pré-Würm. Elle semble avoir plus d'affinités avec Ie groupe nord américain de caligata qu'avec M. camtschatica du nord de la Sibérie. La présence sur M. broweri de la puce asiatique, Oropsylla silantiewi, n'est pas expliquée. Quelques caractéristiques écologiques et éthologiques de M. broweri sont décrites brièvement et comparées avec celles d'autres espèces. Les groupes familiaux de M. broweri hibernent dans un meme terrier dont l'entrée est bouchée; la copulation à lieu avant que les animaux sortent de leur abri hivernal, it la mi-mai ; ils se servent de leurs glandes faciales pour marquer leur territoire.

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An updated checklist of the Cerambycidae of Costa Rica is presented. This new version includes 1,071 species and subspecies in 429 genera, 69 tribes, and six subfamilies. Of these, 181 are new country records and 136 species are known only from Costa Rica. In addition, provincial distribution data are provided for each species. The checklist supports a wealth of scientific literature in many other groups of flora and fauna indicating Costa Rica has high species richness of cerambycid beetles. Se presenta una lista actualizada de los Cerambycidae de Costa Rica. Esta nueva versión incluye 1.071 especies y subespecies en 429 géneros, 69 tribus, y seis subfamilias. De estas, 181 son nuevos registros para el país y 136 especies se conocen solamente de Costa Rica. Adicionalmente, para cada especie se incluyen datos sobre su presencia en las diferentes provincias. La lista concuerda con una gran cantidad de literatura científica en muchos otros grupos de flora y fauna que muestran que Costa Rica tiene una alta riqueza de especies.

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Larvae of Potamophilops cinereus (Blanchard, 1841) from Brazil, Sao Paulo, Ribeirao Grande (Fazenda Intervales, Rio Carmo) are described for the first time and illustrated. The larvae were found associated with adults. The larva of P. cinereus is most similar to larvae of species of the Mexican and Central American genera Disersus Sharp and Hispaniolara Brown, but can be easily distinguished chiefly by the head being not visible when seen from above, due to being concealed by the anterior projection of the pronotum. Comparisons of the three genera are presented. Photographs of the adult habitus of P. cinereus are also furnished. A key to the larvae of the genera of Larainae of Brazil is included.

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Three new species of Triplonychus Candeze, T. cruspinosus sp. nov., T. crassifemoris sp. nov. and T. tibialatus sp. nov., and a new species of Globothorax Fleutiaux, G. latidens sp. nov., from Brazil are described. Illustrations, photographic and SEM images are presented. A review of the diagnostic generic characters and a key to the species of Triplonychus and Globothorax from Brazil are also given.

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Cypermethrin dust was evaluated as a tool for the integrated management of lesser mealwonns (also called the darkling beetle), Alphitobius diaperinus (Panzer). This experiment examined the efficacy of the cypermethrin against adult and late instar lesser mealwonns under laboratory conditions. Two bioassay methods were evaluated, using either a petri plate or a covered plastic container simulating poultry house conditions. In the simulated conditions, two different samples were used and cypermethrin was either dusted onto the surface of the container or was directly dusted onto the bottom. The LC50 for adults was 636.6 ppm, however, 929.7 ppm of cypermethrin dust was needed to achieve a 50% mortality rate in late instar larvae 24 h after the administration of the insecticide. A similar trend was observed in the simulated poultry houses when the adult mortality was > 90% while effectiveness in late in. star larvae was decreased, i.e., between 50 and 85%. Significant differences in the toxicity profiles were observed in larvae mortality when cypermethrin it was dusted directly onto the litter surface, compared to the bottom of the container. We have verified that cypermethrin dust is available for use in poultry houses however, toxicity profiles of lesser mealworm may depend on the beetle's stage of development and method of application