The advantages of semiochemical-based attract and kill techniques in insect pest management.

Introduction: Semiochemicals (chemicals impacting insect behavior) have been employed in species-specific, ecologically friendly insect pest control strategies through a wide variety of mechanisms, many of which do not require the application of conventional insecticides. These include mating disruption?application of sex pheromones in such a way that male insects are unable to locate a female mate, reducing the size of the pest population in the treated area over time?mass trapping, and repellency. However, semiochemical attractants can also be used in combination with small amounts of chemical toxicants, a strategy called attract and kill (A&K)

The advantages of semiochemical-based attract and kill techniques in insect pest management: agricultural case studies.

Introduction: While the advantages of semiochemical-based pest control technologies over traditional insecticides are well-documented (reduced hazards to non-targets and the environment, lower risk of resistance, etc.), many strategies employing these behavior-manipulating compounds to protect agricultural crops are relegated to small niche markets,due to their limited applicability. Since most semiochemicals are species-specific, they can usually target only one pest at a time. However, this is not always the case, as we will demonstrate through this discussion of four of ISCA Technologies? attract and kill (A&K) formulations

Semiochemical attractants for fruit flies of agricultural importance.

Introduction: Fruit flies are among the most damaging agricultural pests worldwide. To combat their devastating impacts on a wide variety of crops, most growers rely on organophosphate insecticides to manage these pests in their fields. Overuse of organophosphates has been implicated in secondary pest outbreaks, negative impacts on beneficial insects, environmental contamination, hazards to human health, and resistance development. With increasingly stringent regulations limiting use of these insecticides, growers have been challenged with finding more effective, sustainable fruit fly control techniques

DISTRIBUIÇÃO E BIOMASSA DE MACROALGAS EM UM MANGUEZAL DA BAÍA DA BABITONGA, SC: RESULTADOS PRELIMINARES

This work aims to assess distribution and biomass of epiphyte macroalgae of mangrove roots in the Babitonga Bay. The macroalgae were collected monthly in three topographyc levels into the mangrove (Places A, B and C). In each place the collect was stratified in the trees (0 to 10 cm high, 10 to 20 cm , etc). The observed Rhodophyta, from higher to smaller biomass, were: Bostrychia calliptera, Bostrychia pinnata, Bostrychia radicans f. radicans, Bostrychia montagnei, Catenella caespitosa, Caloglossa leprieurii, Bostrychia tenella, Caloglossa ogazawaraensis, Bostrychia radicans f. moniliforme, Bostrychia moritziana, Polysiphonia howei, Bostrychia binderi, Gelidium spp., Polysiphonia tepida. The observed Chlorophyta were: Bloodleopsis pusilla, Cladophoropsis membranacea, Rhizoclonium spp., Ulvaria oxysperma, Enteromorpha spp. There are strong variation on horizontal and vertical biomass and on contribution of each species to total biomass. In the mangrove fringe (place A) the algae occur from 0 to 60 cm high in the trees, the mean biomass along this high varies 30 and 45 g m-2 of substrate. Higher values of biomass occur between 10 and 30 cm high, rising to 75 g m-2. On place B (intermediate tidal flooding) the algae occur from 0 to 30 cm high in the trees, the mean biomass along this high varies 20 and 30 g m-2 of substrate. Higher values of biomass occur between 0 and 10 cm high (50 g m-2 of substrate), but high values may also occur between 10 and 20 cm high. In the inner mangrove (place C) the algae occur from 0 to 20 cm high in the trees, the mean biomass along this high varies 10 and 20 g m-2 of substrate. Like place B, higher values of biomass occur between 0 and 10 cm high (35 g m-2 of substrate), but high values may also occur between 10 and 20 cm high. The green algae, Bloodleopsis pusilla, Cladophoropsis membranacea, Rhizoclonium, and the red algae, Bostrychia montagnei, Caloglossa leprieurii and Caloglossa ogazawaraensis were mainly present from 0 to 10 cm high, and rarely occur above 20 cm. Bostrychia radicans f. radicans presents the most broad distribution, has the higher frequency of occurrence in all places and all strata, and it is the main algae in the upper strata. The higher values of biomass, specially on place A, are due to Bostrychia calliptera and Bostrychia pinnata. This two algae also have a broad vertical and horizontal distribution, but they have higher values from 10 to 30 cm high. The results found until now suggest that macroalgae may be an important component of mangrove primary production. Meanwhile, to evaluate the mangrove magroalgae biomass, we need to include algae epiphytic on pneumatophores. And to evaluate the contribution of these algae to the total primary production of the mangrove, it will be necessary to complement biomass data with ecophysiological experiments, including the responses of growth and photosynthetic rates to environmental factors.Este trabalho tem como objetivo determinar a distribuição e quantificar a biomassa de macroalgas presentes nas raízes e troncos das árvores de manguezal da Baía de Babitonga. Para tal, as macroalgas foram coletadas mensalmente (setembro/1997 a junho/1998) em 3 níveis topográficos dentro do manguezal (Linhas A, B e C). Em cada linha a coleta foi estratificada de acordo com a altura das algas no tronco (0 a 10 cm de altura, 10 a 20 cm , etc). As espécies de Rhodophyta observadas, em ordem decrescente de biomassa, foram: Bostrychia calliptera, Bostrychia pinnata, Bostrychia radicans f. radicans, Bostrychia montagnei, Catenella caespitosa, Caloglossa leprieurii, Bostrychia tenella, Caloglossa ogazawaraensis, Bostrychia radicans f. moniliforme, Bostrychia moritziana, Polysiphonia howei, Bostrychia binderi, Gelidium spp., Polysiphonia tepida. As Chlorophyta são Bloodleopsis pusilla, Cladophoropsis membranacea, Rhizoclonium spp., Ulvaria oxysperma, Enteromorpha spp. Há uma forte variação horizontal e vertical na biomassa e na contribuição de cada espécie para a biomassa total. Na franja do manguezal (linha A) as algas ocupam uma altura de 60 cm, e a biomassa média por tronco varia entre 30 e 45 g m-2 de tronco. A maior biomassa ocorre entre 10 e 30 cm, chegando a 75 g m-2 de tronco. Na porção intermediária (linha B) as algas ocupam uma altura de 30 cm e a biomassa média varia entre 20 e 30 g m-2 de tronco. A biomassa é maior nos primeiros 10 cm (50 g m-2 de tronco), mas pode atingir altos valores também entre 10 e 20 cm. Na porção interna do manguezal (linha C) as algas ocupam uma altura de 20 cm, e a biomassa média varia entre 10 e 20 g m-2 de tronco. Assim como na linha B, a biomassa é maior nos primeiros 10 cm (35 g m-2 de tronco), mas pode atingir altos valores também entre 10 e 20 cm. As algas verdes Bloodleopsis pusilla, Cladophoropsis membranacea, Rhizoclonium, e as algas vermelhas Bostrychia montagnei, Caloglossa leprieurii e Caloglossa ogazawaraensis estão presentes principalmente nos primeiros 10 cm de altura, raramente ocorrendo acima de 20 cm. Bostrychia radicans f. radicans é a alga mais amplamente distribuída, com maior freqüência de ocorrência e a mais abundante na região superior do tronco nas três linhas. As algas que apresentam a maior biomassa, especialmente na linha A, são Bostrychia calliptera e Bostrychia pinnata, que também apresentam distribuição vertical e horizontal ampla, mas são mais abundantes entre 10 e 30 cm de altura. Os resultados obtidos até o momento indicam que as macroalgas podem ser vistas como um componente produtor representativo dentro do manguezal. Entretanto, para uma avaliação da biomassa de macroalgas no manguezal como um todo, é necessário quantificar a biomassa de algas em pneumatóforos. Para avaliar a contribuição destas algas para a produção primária do manguezal, os dados de biomassa devem ser complementados com experimentos de crescimento e produtividade, com relação aos fatores ambientais

Spatial Evaluation and Modeling of Dengue Seroprevalence and Vector Density in Rio de Janeiro, Brazil

Dengue is a major public health problem in many tropical regions of the world, including Brazil, where Aedes aegypti is the main vector. We present a household study that combines data on dengue fever seroprevalence, recent dengue infection, and vector density, in three neighborhoods of Rio de Janeiro, Brazil, during its most devastating dengue epidemic to date. This integrated entomological–serological survey showed evidence of silent transmission even during a severe epidemic. Also, past exposure to dengue virus was highly associated with age and living in areas of high movement of individuals and social/commercial activity. No association was observed between household infestation index and risk of dengue infection in these areas. Our findings are discussed in the light of current theories regarding transmission thresholds and relative role of mosquitoes and humans as vectors of dengue viruses

BANCOS DE Sargassum cymosum (PHAEOPHYCEAE) NA ENSEADA DE ARMAÇÃO DO ITAPOCOROY, PENHA, SC: BIOMASSA E RENDIMENTO EM ALGINATO

The seaweed Sargassum occurs in large beds along Brazilian Coast, mainly in Southern and Southeastern areas. This seaweed is very important to local fauna and flora. It is also economically important mainly due alginate to production. Several kinds of approaches are needed to planning its sustainable management. This work aims to evaluate the size of subtidal Sargassum cymosum beds in Armação do Itapocoroy Bay (Penha, SC), quantifying its spatial variations on biomass and associated seaweed community, and also evaluate alginate yield separately for vegetative and reproductive branches, for each bed. The Sargassum beds area in Armação do Itapocoroy Bay reached 14,137 m2. Total estimated biomass in the bay was 17.90 ± 9.07 ton wet mass. Mean biomass ranged from 142,64 (± 34,25) to 214,76 (±131,68) g dry mass m-2 between the beds. The alginate yield ranged from 18.63 to 25.00%, and reproductive branches yield was higher than vegetative branches yield. Reproductive structures alone yield about 30%. Despite many additional works are needed, these results indicate potential for Sargassum exploitation in Santa Catarina Coast.A macroalga Sargassum forma extensos bancos ao longo de toda a costa brasileira, principalmente no litoral das regiões sudeste e sul. Esta alga possui vasta importância para a fauna e flora dos ambientes onde ocorre, além de possuir uma importante aplicabilidade econômica, principalmente como fonte de alginato. Portanto, estudos que conduzam ao desenvolvimento de planos viáveis de manejo são necessários. Este trabalho buscou quantificar bancos de Sargassum cymosum na Enseada de Armação do Itapocoroy, SC, e avaliar o rendimento da alga em alginato, considerando ramos reprodutivos e vegetativos separadamente. A composição da comunidade de algas associadas também foi analisada. A área total de cobertura dos bancos foi estimada em 14.137 m², correspondendo a uma biomassa instantânea de 17,90 (± 9,07) toneladas de Sargassum (massa úmida). A biomassa média de Sargassum variou de 142,64 (± 34,25) a 214,76 (±131,68) g ms m-2 (massa seca) entre os bancos. O rendimento em alginato obtido oscilou entre 18,63% e 25,00%, sendo que os ramos reprodutivos da planta tendem a apresentar rendimentos mais elevados do que os vegetativos. As estruturas reprodutivas sozinhas renderam cerca de 30% do peso em alginato. Apesar de que investigações adicionais sejam imprescindíveis, estes resultados indicam um potencial para a explotação de Sargassum na costa de Santa Catarina