Optimal reactive power flow via the modified barrier Lagrangian function approach

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of carrion smell and rebaiting time on the efficiency of pitfall traps to dung beetle sampling

Dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) are very useful insects, as they improve the chemo-physical properties of soil, clean pastures from dung pads, and help control symbovine flies associated with bovine cattle. Their importance makes it fundamental to sample and survey them adequately. The objectives of the present study were to determine the influence of decaying insects trapped in pitfalls on the attractiveness of Moura pig Sus scrofa L. (Suidae) and collared peccary Tayassu tajacu (L.) (Tayassuidae) dung used as baits to lure dung beetles, and to establish how long these baits remain attractive to dung beetles when used in these traps. Some dung beetle species seemed to be able to discriminate against foul smell from decaying insects within the first 24 h, hence decreasing trap efficiency. This was more evident in peccary dung-baited traps, which proved to be the least attractive bait. Attractiveness lasted only 24 h for peccary dung, after which it became unattractive, whereas the pig dung bait was highly attractive for 48 h, after which its attractiveness diminished but was not completely lost.

Dinâmica populacional e incidência de moscas-das-frutas e parasitoides em cultivares de pessegueiros (Prunus Persica L. Batsch) no município de presidente prudente-sp

Esta pesquisa teve como objetivos avaliar a dinâmica populacional e registrar a diversidade de moscas-das-frutas (Diptera: Tephritoidea) em cultivares de pessegueiro Tropical, Talismã, Aurora 2, Aurora 1, Dourado 2 e Doçura 2, enxertadas sobre os porta-enxertos 'Okinawa' e Umê, em Presidente Prudente-SP. Foram realizadas as correlações da dinâmica populacional com a temperatura e a precipitação, e também a infestação com as características químicas dos frutos, Sólidos Solúveis e Acidez Titulável. No período de julho de 2004 a dezembro de 2006, a dinâmica populacional de moscas-das-frutas foi obtida através de coletas semanais de moscas-das-frutas em armadilhas McPhail, e a incidência foi determinada através da coleta de 30 frutos/planta/cultivar. O delineamento estatístico adotado foi o inteiramente casualizado, com cinco repetições. Ceratitis capitata foi predominante nas cultivares de pessegueiros estudadas. Não foi observada correlação significativa entre população de moscas-das-frutas e as variáveis de temperatura e precipitação, e sólidos solúveis e ácidez titulável. Entre as cultivares de pêssego, Aurora 2 apresentou maior infestação por C. capitata, da ordem de 22 e 23% nos anos 2004 e 2006, respectivamente. Também foi registrada a incidência de Neosilba spp. em frutos de pêssego. Doryctobracon areolatus (Braconidae), Tetrastichus giffardianus (Eulophidae) e Pachycrepoideus vindemmiae (Pteromalidae) foram recuperados de pupários de Tephritidae.

Dinâmica populacional da mosca-dos-chifres (Haematobia irritans) em bovinos da raça Guzerá e mestiço em Selvíria, MS

Aiming to know the population dynamics of horn fly on cattle in the municipality of Selviria, MS, Brazil, a study was conducted from March 2004 to June 2005 in the Education, Research and Extension Farm, from Unesp - Campus de Ilha Solteira, located in the municipality of Selviria, MS. It was used IS cows of the Guzera breed and 15 crossbred (Guzera X Holstein-Friesian), respectively 3 and 4 years old, naturally infested. During the experimental period these animals did not receive any insecticide treatment. Visual fly counting by on back region of the animals was carried out at 14 day interval. The horn fly showed two peaks of infestation during the year, one in April and another in October. In the months of highest infestation, the average number of flies did not exceed a 104. The months in which was significant difference between crossbred and Guzera breed was in April, May, August and September 2004 and February, March and April 2005, always with crossbred with higher infestation. In the region studied Haematobia irritans was present throughout the year.

A ocupação urbana do entorno de zonasde proteção ambiental de natal, suas condições de sustentabilidade e a relação com a ocorrência de insetos vetores

This study started from the hypothesis of the existence of a relation between the type of the urban occupation concerning to the sustainability conditions at the proximity of Environment Protected Zones and the occurrence of vectors insects in Natal, Rio Grande do Norte, Brazil. This research, which used data available by the City Administration Health and Urbanization Secretaries (respectively SMS and SEMURB), in the time period of 2006 to 2008, aimed to characterize the study site in terms of urban occupation, relating it to social environmental aspects of land occupation and the occurrence of vectors insects. This study is presented in two papers, the first one linking the occurrence of vectors insects and sustainable development indicators and the second relating the incidence of reported cases of Dengue and Dengue Hemorrhagic Fever (DHF) and the occurrence of larvae infection indexes of Aedes aegypti, in Natal, Rio Grande do Norte State. In the first paper, was made a correlation between Dengue Fever vectors and Visceral and Tegumentar Leishmaniasis vectors and sustainable development indicators, selected from IDS Brasil- 2008. Through factorial analysis a Sustainability Index (SI) was acquired for each region, the northern region of the municipality obtained lower numbers than southern region, which, in its turn, presented better sustainability conditions. Linking this index to vector infestation parameters shows a high significant correlation between the SI and the Breteau Index of Aedes aegypti (p=0,028) as well as with SI and sand flies infestation index (p=0,01). Higher rates in vectors infestation in regions with a lower Sustainable Development Index demonstrates that this index can be used to determine the increasing of probability of Aedes and sand flies occurrence in urban environment. The second paper analyzed the occurrence of the main vector of Dengue and DHF, the Aedes aegypti mosquito, and the relation between larvae infection indexes of this insect and reported cases of the diseases. This study revealed unexpected relation where areas with higher Breteau s Indexes showed lower infection rates of Dengue Fever, although showing high incidence of DHF

Porcentagem de eclosão de ovos de haematobia irritans (l.) (diptera: muscidae) em laboratório

The laboratory production of the horn fly is still an important resource for research. Several authors have already observed that viability of immature stages varies according to arthropod species. In this study were observed the Haematobia irritans egg percentage hatching. Bovine faeces was obtained from animals grazing pastures (Brachiaria decumbens) was collected and used immediately or placed in a refrigerator (2-3 degrees C). Horn flies were captured in bovine to get eggs placed in filter paper on dung and incubate at 32 +/- 2 degrees C and 80% RH for larvae raring. The results were based on the number of hatched eggs and we observed 83,0% percent of larvae rearing.

New mariner elements in Anastrepha species (Diptera: Tephritidae)

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

Desenvolvimento das gônadas de Dermatobia hominis (Diptera: Cuterebridae)

O trabalho descreve o desenvolvimento das gônadas do berne (D. hominis) durante o período pupal. As pupas desenvolvidas de larvas com peso superior a 650 mg, deram imagos fêmeas, enquanto que as desenvolvidas daquelas pesando entre 500 e 650 mg deram macho, tendo havido um erro ao redor de 5%. Até o oitavo dia de pupação os testículos crescem mais que os ovários; a partir daí diminui o desenvolvimento, parando de crescer entre o vigésimo e vigésimo quinto dias. A espermatogênese inicia por volta do sétimo dia de pupa quando é grande o número de espermatócitos. No décimo dia alguns testículos apresentam considerável número de espermátides e os espermatozóides começam a aparecer por volta do vigésimo dia. A espermiogênese desenvolve-se sem interrupção e ao final da pupação quase toda loja testicular está repleta de espermatózóides. Os machos começam a nascer dois dias antes das fêmeas. Nessas, os ovaríolos aparecem formados por volta do oitavo dia de pupa; os folículos se individualizam por volta do vigésimo dia de pupa onde se distingue os trofócitos com núcleos politênicos e citoplasmas bem basófilos, enquanto o ovócito tem citoplasma mais acidófilo e núcleo com cromatina bastante frouxa. A vitelogênese tem início ao redor do vigésimo quinto dia de pupa e se completa ao nascimento da imago. A ligação das gônadas com suas respectivas estruturas somáticas acontece ao redor do décimo terceiro dia de pupação.

Possible causes of spatial variability in Diatraea saccharalis Fabr. (Lep., Crambidae) and its parasitoid populations in sugarcane fields in Brazil

Based on the large data set stored in some sugarcane mills regarding the biological control programme of Diatraea saccharalis using the parasitoids Cotesia flavipes and tachinid flies, the aim of the present study was to determine whether sugarcane varieties, number of cuts and plant ages are major determinants in promoting spatial variability in D. saccharalis, C. flavipes and tachinid fly populations in sugarcane fields in the state of São Paulo (Brazil). The data set used to support this study was provided by the Sao Joao and Barra sugarcane mills. Coefficient of variation was adopted as a measure of the spatial variability of population density. Spatial variability was estimated for the total density of D. saecharalis (parasitized + unparasitized larvae), and also for D. saccharalis larvae parasitized by tachinids and by C. flavipes. Statistical analysis revealed that the spatial variation in D. saccharalis populations was influenced by the number of cuts and by plant ages in the Barra and Sao Joao Mills, respectively. Similar results were obtained for D. saccharalis larvae parasitized by tachinids; however, in the Sao Joao Mill, the spatial variability of these populations was also influenced by the different number of varieties. Finally, considering D. saccharalis larvae parasitized by C. flavipes, no significant regressions with any of the three categories were observed for both sugarcane mills. The multitrophic implications for this agricultural system are also discussed.

Evidences of non-additive effects of multiple parasitoids on Diatraea saccharalis Fabr. (Lep., Crambidae) populations in sugarcane fields in Brazil

Biological control is a relatively benign method of pest control. However, considerable debate exists over whether multiple natural enemies often interact to produce additive or non-additive effects on their prey or host populations. Based on the large data set stored in the Sao Joao and Barra sugarcane mills (state of São Paulo, Brazil) regarding the programme of biological control of Diatraea saccharalis using the parasitoids Cotesia flavipes and tachinid flies, in the present study the author investigated whether the parasitoids released into sugarcane fields interfered significantly with the rate of parasitized D. saccharalis hosts. The author also observed whether there was an additive effect of releasing C. flavipes and tachinids on the rate of parasitized hosts, and looked for evidence of possible negative effects of the use of multiple parasitoid species in this biological control programme. Results showed that C. flavipes and the tachinids were concomitantly released in the Barra Mill, but not in the Sao Jao Mill. Furthermore, in the Barra Mill there was evidence that the parasitoids interacted because the percentage of parasitism did not increase after the release of either C. flavipes or tachinids. In the Sao Joao Mill, when both parasitoid species were released out of synchrony, both the percentage of parasitism by C. flavipes as well as that of the tachinids increased. When large numbers of tachinids were released in the Barra Mill, they caused a significant lower percentage of parasitism imposed by C. flavipes. The implications of the results as evidence of non-additive effects of C. flavipes plus tachinids on D. saccharalis populations are discussed.

Prey choice by Nesticodes rumpes (Araneae, Theridiidae) on Musca domestica (Diptera, Muscidae) and Dermestes ater (Coleoptera, Dermestidae)

Nesticodes rufipes is widely distributed in tropical and subtropical regions, being strongly associated with humans. However, few behavioral and ecological studies have investigated interspecific interactions between these spiders and insects of medical and veterinary importance. Here, we have investigated prey choice by N. rufipes when two different prey species, Musca domestica and Dermestes ater, were offered simultaneously. We also quantified the capture of these prey types by this predator in a poultry house and analyzed the association between prey-choice with physical characteristics of the prey. Finally, we discuss whether there is an antagonistic intraguild interaction in such a system composed of N. rufipes (top predator), D. ater (predator of larvae of M. domestica and prey of N. rufipes) and M. domestica (N. rufipes' prey). We found that Musca domestica were more abundant than D. ater in N. rufipes webs in the poultry house. Spiders given a choice of adults of M. domestica plus adults of D. ater, and also on adults plus larvae of M. domestica, preyed more on adult flies than on the other prey types. This preference was probably associated with the lesser mass and shorter lengths of adult flies. Our experiments demonstrated that the predation impact of N. rufipes on D. ater is low when compared to M. domestica. This result provides evidence that an antagonistic interaction between these predators does not occur, suggesting that they are in fact acting either synergistically or additively on M. domestica prey.

Dynamics of experimental populations of native and introduced blowflies (Diptera: Calliphoridae): mathematical modelling and the transition from asymptotic equilibrium to bounded oscillations

The equilibrium dynamics of native and introduced blowflies is modelled using a density-dependent model of population growth that takes into account important features of the life-history in these flies. A theoretical analysis indicates that the product of maximum fecundity and survival is the primary determinant of the dynamics. Cochliomyia macellaria, a blowfly native to the Americas and the introduced Chrysomya megacephala and Chrysomya putoria, differ in their dynamics in that the first species shows a damping oscillatory behavior leading to a one-point equilibrium, whereas in the last two species population numbers show a two-point limit cycle. Simulations showed that variation in fecundity has a marked effect on the dynamics and indicates the possibility of transitions from one-point equilibrium to bounded oscillations and aperiodic behavior. Variation in survival has much less influence on the dynamics.

Knockdown resistance in pyrethroid-resistant horn fly (Diptera: Muscidae) populations in Brazil

Com o objetivo de verificar a ocorrência e determinar a frequência da mutação kdr (knock down resistance) em populações de Haematobia irritans (mosca-dos-chifres) resistentes aos piretróides, foram analisados 1.804 indivíduos de 37 populações de todas as Regiões do Brasil. Com exceção da Região Nordeste, o kdr (knock down resistance gene) foi encontrado em populações de todas as regiões. A mutação não foi detectada em 87,08% dos indivíduos. Entretanto, o gene foi amplificado de 12,92% das moscas, das quais 11,70% se mostraram heterozigotas resistentes e 1,22% homozigotas resistentes. em todas as populações verificou-se equilíbrio de acordo com a Lei de Hardy e Weinberg, exceto uma com excesso de heterozigotos. Entretanto, quando agrupamos diferentes populações numa metapopulação de acordo com a região geográfica, é possível observar um desvio nas populações Centro-Oeste, Sul e Sudeste, indicando isolamento populacional e que a ocorrência do kdr é provavelmente um efeito independente, talvez refletindo a estratégia de uso do inseticida de cada produtor. Apesar da resistência aos piretróides estar disseminada por todo o país, apenas 48% das populações resistentes apresentaram o kdr, e a frequência de indivíduos kdr nas populações resistentes se mostrou bastante baixa. À exceção da Região Nordeste, o mecanismo de resistência ligado ao kdr ocorre em todo o país.

Short Report: Heterogeneity of Leishmania infantum chagasi Kinetoplast DNA in Teresina (Brazil)

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

Occurrence of Microcerella halli (Engel) (Diptera, Sarcophagidae) in snake carrion in southeastern Brazil

Occurrence of Microcerella halli (Engel) (Diptera, Sarcophagidae) in snake carrion in southeastern Brazil. The occurrence of 27 second-instar larvae of the flesh fly Microcerella halli (Engel, 1931) (Diptera, Sarcophagidae) in a carcass of a snake usually called as Urutu, Bothrops alternatus (Dumeril, Bibron & Dumeril, 1854) (Serpentes, Viperidae, Crotalinae) is reported. The snake was kept in captivity in a snake farm in Morungaba, São Paulo state, Brazil. Descriptions of reptile carcass colonization by insects and general biological data of this flesh fly are scarce and this necrophagic behavior is described for the first time in literature.