48 research outputs found

    DOES SULPHUR EXPEL THE COFFEE BERRY BORER FROM Coffea arabica L. FRUITS?

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    Technicians and insecticide retailers recommend adding sulfur to the insecticide mixture to expel coffee borer females (Hypothenemus hampei ) from the fruit. The objective in this study was to verify if sulfur expels the coffee borer from the fruit and what the cost associated with the use of sulfur in the insecticide mixture is. Perforated fruits were collected from coffee crops (Red Catuaí, IAC 144) during the granulation phase for the experiments and divided into two lots. The first lot was used to verify the effectiveness of sulfur to expel the borer, and the second to evaluate the effect of temperature x sulfur source x expelling effect on the borer. Sources of sulfur tested were: SK30 and Kumulus DF. The first experiment was the treatments: sulfur sources (two + control without sulfur), two plastic containers (open and closed), five repetitions (factorial: 3 x 2). The second were the treatments: sulfur sources, plastic containers and under two temperatures, factorial 3x2x2. The number of adult females that left the fruits within 24 and 48 h was evaluated. There was no difference in the number of females that abandoned the fruits between treatments with sulfur and control (P> 0.05). It was concluded that sulfur does not expel H. hampei from C. arabica fruits

    Physico-chemical characteristics and productivity of tomato plants in function of nitrogen sources and doses

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    The objective of this study was to evaluate the effect of nitrogen sources and rates on the physicochemical characteristics and yield of tomato plants. Forty hybrids were cultivated at 100 and 400 kg ha-1 of N, combined with four sources (urea, ammonium sulfate, ammonium nitrate and calcium), plus a treatment without N application in a randomized complete block design four replicates. Size, stem diameter, number of leaves, SPAD (Soil Plant Analysis Development), leaf nitrogen, number of fruits / plants, fruit firmness, bark thickness and average fruit size, ° BRIX, pH, calcium, potassium and sodium in fruits. There was an increase in SPAD index, Brix and longitudinal diameter of fruits as a function of the N dose. The use of ammonium nitrate and calcium provided stronger fruits. Urea and ammonium nitrate provided the highest pH value in tomato fruits. The application of the 100 kg ha-1 dose of N resulted in the highest potassium content in fruits. The highest productivity was obtained with the application of sources containing ammonium and the lowest in the control treatment. Sources and doses of nitrogen fertilizers influenced growth, productivity and parameters related to tomato quality

    Physiological selectivity of insecticides from different chemical groups and cuticle thickness of Protonectarina sylveirae (Saussure) and Brachygastra lecheguana (Latreille)

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    O uso de inseticidas mais tóxicos para uma praga do que a saúde natural pode favorecer o salvamento desses organismos benéficos. Este estudo teve como objetivos fisiológicos distanciadores de inseticidas de separações científicas para Vespidae Protonectarina sylveirae (Saussure, 1854) e Brachygastra lecheguana. (Latterille, 1824) e espessura de cutícula para avaliação da tolerância entre os 2 anos estes mesmos inseticidas. Como imersas foram folhas de milho (10 x 10 cm) em solução inseticida em dose (100%), subdose (50%) e água destilada (controle) por 5 segundos. Nós podemos ler as folhas e depois embalamos em placas de Petri.Como 20 vespas, por placa, receberam 10% de mel e as placas foram fechadas com tecido de organza fino e elastificadas. Após 24 horas, avaliamos uma porcentagem de vespas mortas. O inseticida alfa-cipermetrina foi altamente tóxico para P. sylveirae e B. lecheguana em dose (100%) e subdose (50%). Os inseticidas Novaluron, chlorantraniliprole, spinosad e indoxacarb foram pouco tóxicos para P. sylveirae e B. lecheguana. dose (100%) e subdose (50%). A alta toxicidade dos inseticidas metomil + novalurom, clorantraniliprole + lambda-cialotrina e deltametrina a P. sylveirae corresponde à menor espessura da cutícula.Portanto, os inseticidas novalurom, clorantraniliprole, spinosad e indoxacarb da selectividade fisiológica para P. sylveirae e B. lecheguana .

    Armadilha de baixo custo para monitoramento de Cerambycidae em plantações florestais no Brasil

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    The objective of this work was to evaluate the use of a low-cost trap to capture Cerambycidae in different seasons in planted forests in Brazil. Thirty polyethylene-terephthalate trap bottles per hectare were used, disposed at every 50 m. The traps were red painted and contained glass flasks with a mixture of ethanol, methanol and benzaldehyde. There were soap and water at the trap bottom. The traps were checked biweekly for beetle presence. Sampling time required one minute per sample, and traps were easy to use. Total sampling cost, including materials and labor, was US 13.46persample.SixCerambycidaespecieswerecapturedalongthedryandrainyseasons.Oobjetivodestetrabalhofoiavaliarousodeumaarmadilhadebaixocusto,paracapturarCerambycidaeemdiferenteseˊpocasdoano,emflorestascultivadasnoBrasil.Foramutilizadas30armadilhasdegarrafasdepolietilenotereftalatoporhectare,posicionadasacada50 m.As armadilhaseramdecorvermelhaecontinhamfrascosdevidrocommisturadeetanol,metanolebenzaldeıˊdo.Na parteinferiordaarmadilha,haviaaˊguaesaba~o.A cadaduassemanas,asarmadilhasforamverificadasquantoaˋpresenc\cadebesouros.O tempodeamostragemnecessaˊriofoide1minporamostraeasarmadilhasforamdefaˊcilmanuseio.O custototaldeamostragem,incluindomateriaisema~odeobra,foideUS 13.46 per sample. Six Cerambycidae species were captured along the dry and rainy seasons.O objetivo deste trabalho foi avaliar o uso de uma armadilha de baixo custo, para capturar Cerambycidae em diferentes épocas do ano, em florestas cultivadas no Brasil. Foram utilizadas 30 armadilhas de garrafas de polietileno-tereftalato por hectare, posicionadas a cada 50 m. As armadilhas eram de cor vermelha e continham frascos de vidro com mistura de etanol, metanol e benzaldeído. Na parte inferior da armadilha, havia água e sabão. A cada duas semanas, as armadilhas foram verificadas quanto à presença de besouros. O tempo de amostragem necessário foi de 1 min por amostra e as armadilhas foram de fácil manuseio. O custo total de amostragem, incluindo materiais e mão de obra, foi de US 13,46 por amostra. Seis espécies de Cerambycidae foram capturadas nas estações secas e chuvosas

    New accessions of tomato resistant to whitefly biotype B

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    O objetivo deste trabalho foi selecionar novas fontes de resistência a Bemisia tabaci biótipo B, entre 34 acessos de tomateiro (Lycopersicon esculentum), do Banco de Germoplasma de Hortaliças da UFV. Avaliaram-se os números de adultos, ovos e ninfas por planta, além da densidade de tricomas. Detectaram-se diferenças entre os acessos nas variáveis avaliadas. Os acessos BGH-166, BGH-616, BGH-850, BGH-990, BGH-2102 e BGH-2125 apresentaram menor número de adultos, ovos e ninfas por planta e tiveram menor densidade de tricomas. A resistência dos acessos de tomate à mosca-branca foi associada a uma menor densidade de tricomas.The objective of this work was to evaluate resistance to Bemisia tabaci biotype B in 34 tomato (Lycopersicon esculentum) accessions from the Banco de Germoplasma de Hortaliças of UFV. The number of adults, eggs and nymphs per plant besides of trichome density were evaluated. Differences between accessions were found for the evaluated variables. Accessions BGH-166, BGH-616, BGH-850, BGH-990, BGH-2102 and BGH-2125 presented less infestation of adults, eggs and nymphs per plant and showed lower trichome density. The resistance of these tomato accessions to whitefly was associated to a lower trichome density

    New accessions of tomato resistant to whitefly biotype B

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    O objetivo deste trabalho foi selecionar novas fontes de resistência a Bemisia tabaci biótipo B, entre 34 acessos de tomateiro (Lycopersicon esculentum), do Banco de Germoplasma de Hortaliças da UFV. Avaliaram-se os números de adultos, ovos e ninfas por planta, além da densidade de tricomas. Detectaram-se diferenças entre os acessos nas variáveis avaliadas. Os acessos BGH-166, BGH-616, BGH-850, BGH-990, BGH-2102 e BGH-2125 apresentaram menor número de adultos, ovos e ninfas por planta e tiveram menor densidade de tricomas. A resistência dos acessos de tomate à mosca-branca foi associada a uma menor densidade de tricomas.The objective of this work was to evaluate resistance to Bemisia tabaci biotype B in 34 tomato (Lycopersicon esculentum) accessions from the Banco de Germoplasma de Hortaliças of UFV. The number of adults, eggs and nymphs per plant besides of trichome density were evaluated. Differences between accessions were found for the evaluated variables. Accessions BGH-166, BGH-616, BGH-850, BGH-990, BGH-2102 and BGH-2125 presented less infestation of adults, eggs and nymphs per plant and showed lower trichome density. The resistance of these tomato accessions to whitefly was associated to a lower trichome density

    Controle massal da broca‑do‑café com armadilhas de garrafa Pet vermelha em cafeeiro

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    The objective of this work was to evaluate the efficacy of red PET‑bottle traps, containing attractive alcoholic volatile compounds, in the mass control of coffee berry borer (Hypothenemus hampei). The evaluations were carried out in four coffee crops, during two years. Nine hundred PET‑bottle traps, painted red, were distributed in three of the four coffee crops; one crop without traps was used as a control. Holes drilled into berries (%) were determined in these crops. There was a reduction in drilled berries in crops with traps, from the 2007/2008 harvest to the 2008/2009 harvest. The highest coffee berry borer densities in traps was observed in the flowering and small‑green berries stages. The red PET‑bottle trap is efficient in the mass control of the coffee berry borer population, since it reduces the percentage of drilled berries in 57%; however, this reduction is not enough to keep borer densities below the control level.O objetivo deste trabalho foi avaliar a eficácia de armadilha de garrafa Pet vermelha contendo compostos voláteis alcoólicos atrativos, no controle massal da broca‑do‑café (Hypothenemus hampei). As avaliações foram realizadas em quatro lavouras de café, durante dois anos. Foram distribuídas 900 armadilhas de garrafa Pet, pintadas de vermelho, em três das quatro lavouras; uma lavoura sem armadilhas foi usada como controle. O broqueamento dos frutos (%) foi determinado nessas lavouras. Houve redução do broqueamento de frutos nas lavouras com armadilhas, da safra 2007/2008 para a safra 2008/2009. As maiores densidades da broca‑do‑café nas armadilhas foram observadas nos estádios de floração e de frutos chumbinho. A armadilha de garrafa Pet vermelha é eficaz no controle massal da população da broca‑do‑café, por reduzir a percentagem de frutos broqueados em 57%; entretanto, essa redução não é suficiente para manter as densidades da broca abaixo do nível de controle

    Can the understory affect the Hymenoptera parasitoids in a Eucalyptus plantation?

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    The understory in forest plantations can increase richness and diversity of natural enemies due to greater plant species richness. The objective of this study was to test the hypothesis that the presence of the understory and climatic season in the region (wet or dry) can increase the richness and abundance of Hymenoptera parasitoids in Eucalyptus plantations, in the municipality of Belo Oriente, Minas Gerais State, Brazil. In each eucalyptus cultivation (five areas of cultivation) ten Malaise traps were installed, five with the understory and five without it. A total of 9,639 individuals from 30 families of the Hymenoptera parasitoids were collected, with Mymaridae, Scelionidae, Encyrtidae and Braconidae being the most collected ones with 4,934, 1,212, 619 and 612 individuals, respectively. The eucalyptus stands with and without the understory showed percentage of individuals 45.65% and 54.35% collected, respectively. The understory did not represent a positive effect on the overall abundance of the individuals Hymenoptera in the E. grandis stands, but rather exerted a positive effect on the specific families of the parasitoids of this order

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
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