22 research outputs found

    Ocorrência e aspectos biológicos do psilídeo do sombreiro no Brasil

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    O sombreiro Clitoria fairchildiana (Howard) é uma planta amplamente distribuída no Brasil sendo muito utilizada em arborizações. Em abril de 2001 foi constatada a ocorrência do psilídeo Euphalerus clitoriae Burckhardt & Guajará neste hospedeiro na Região Metropolitana do Recife, PE. Este trabalho teve como objetivo registrar a ocorrência de E. clitoriae e seus inimigos naturais, e estudar alguns aspectos da biologia deste psilídeo. Foram realizadas coletas semanais de folhas de C. fairchildiana visando à contagem de ninfas de E. clitoriae e formas imaturas e adultos dos inimigos naturais. A população de E. clitoriae variou de 2 a 90 ninfas por folíolo. A percentagem de parasitismo de Aprostocetus sp. variou de 3 a 24%. A curva de freqüência da largura do pigídio dos insetos observados apresentou variação de 120 a 140; 200 a 240; 300 a 380; 460 a 580 e 720 a 820 mm para o primeiro, segundo, terceiro, quarto e quinto ínstares, respectivamente. Os ovos de E. clitoriae apresentaram 7,6 dias de incubação. A fase ninfal apresentou 5,7 dias para o primeiro ínstar, 4,5 dias para o segundo ínstar, 4,8 dias para o terceiro ínstar, 5,0 dias para o quarto ínstar e 6,1 dias para o quinto ínstar. O período de ovo-adulto foi 33,7 dias, a longevidade de fêmeas foi 8,6 dias e a fecundidade de 118 ovos/fêmea. A viabilidade total de formas imaturas foi de 74% e a razão sexual de 0,5.Clitoria fairchildiana (Howard) is a tree largely distributed in Brazil, used for urban arborization. In April 2001, the psyllid Euphalerus clitoriae Burckhardt & Guajará was reported on this plant in the metropolitan areas of Recife, PE, Brazil. This report records the occurrence of E. clitoriae and studies some of its biological aspects in this area. With this purpose, C. fairchildiana leaves were sampled weekly, and E. clitoriae nymphs as well as Aprostocetus sp. larvae and nymphs were collected and counted. The E. clitoriae population ranged from 2 to 90 nymphs per leaflet. The Aprostocetus sp. percentage of parasitism ranged from 3 to 24%. The frequency curve for pygidium width ranged from 120 to 140; 200 to 240; 300 to 380; 460 to 580, and 720 to 820 mm for the first, second, third, fourth, and fifth instars, respectively. The incubation period for E. clitoriae eggs lasted 7.6 days. The nymphal stage lasted 5.7; 4.5; 4.8; 5.0, and 6.1 days for the first, second, third, fourth, and fifth instars, respectively. Development time from egg to adult was 33.7 days. Female longevity 8.6 days, with a daily fecundity of 118 eggs. The total viability of the immature stage was 74%, and the sex ratio was 0.5

    OCORRÊNCIA DO ÁCARO BRANCO Polyphagotarsonemus latus (Banks) EM JAMBU Spilanthes oleracea E OUTRAS PLANTAS HOSPEDEIRAS NO ESTADO DO AMAZONAS

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    Abstract: Spilanthes oleracea is an unconventional vegetable native to the Amazon, is widely cultivated in several municipalities of the North Brazil. Few pests have been found and identified effectively in this culture, with no record to phytophagous mite. Thus, the purpose of this study was to record the first occurrence of Polyphagotarsonemus latus (Banks) in S. oleracea crops, characterizing the damage and reporting the occurrence of other host plants in Central Amazonia. The main damage caused by P. latus in leaf of S. oleracea are hardening and shrinking of the younger leaves, leaving them unfit for marketing.   KEY WORDS: diversity, pest mites, tropical agriculture.RESUMO: O jambu, Spilanthes oleraceae, é uma hortaliça não convencional nativa da Amazônia, amplamente cultivada como hortaliça folhosa em vários municípios da região Norte. Poucas pragas têm sido constatadas e efetivamente identificadas nesta cultura, não havendo nenhum registro de ácaro fitófago. Assim, o objetivo deste trabalho foi registrar pela primeira vez a ocorrência de Polyphagotarsonemus latus (Banks) em cultivos de jambu, caracterizando os danos e relatar a ocorrência deste ácaro em outras plantas hospedeiras no Estado do Amazonas. Os principais danos causados por P. latus em folha de jambu são o enrijecimento e encarquilhamento das folhas jovens, deixando-as impróprias para comercialização. PALAVRAS-CHAVE: ácaros praga, agricultura tropical, diversidade

    Predatory mites and the fungus Neozygites floridana associated with spider mites on soybean, in Rio Grande do Sul, Brazil

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    O objetivo deste trabalho foi verificar a ocorrência de ácaros predadores e do fungo Neozygites floridana, associados a ácaros tetraniquídeos, em soja (Glycine max L.), no Estado do Rio Grande do Sul. Entre 2003 e 2005, foram avaliadas amostras de folhas de soja das principais regiões produtoras do Estado. Essas amostras foram coletadas de diferentes posições da planta e aleatoriamente na lavoura. As espécies de ácaros predadores encontradas foram: Neoseiulus anonymus, N. californicus, Phytoseiulus fragariae, P. macropilis, Proprioseiopsis cannaensis e Galendromus annectens. O fungo N. floridana apresentou ampla distribuição e ocorreu em todas as espécies de tetraniquídeos encontradas: Mononychellus planki, Tetranychus desertorum, T. gigas, T. ludeni e T. urticae.The objective of this work was to verify the occurrence of predatory mites and the fungus Neozygites floridana, associated with spider mites in soybean (Glycine max L.), in Rio Grande do Sul, Brazil. From 2003 to 2005, samples of soybean leaves from the most important soybean producing regions of the state were evaluated. These samples were collected from different positions of the plant and randomly in the field. The predatory mite species found were Neoseiulus anonymus, N. californicus, Phytoseiulus fragariae, P. macropilis, Proprioseiopsis cannaensis, and Galendromus annectens. The fungus N. floridana was widely distributed and occurred in all the spider mite species found: Mononychellus planki, Tetranychus desertorum, T. gigas, T. ludeni and T. urticae

    Chemical compositions of essential oil of piper species from atlantic forest of Amazonia, Brazil

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    Essential oils from the leaves of Piper japurense (Miq.) C. DC., P. coariense Yunk., P. auriculifolium Yunk., P. curtistilum C.DC., P. alatipetiolatum Yunk. and P. brevesanum Yunk. from the Amazon Forest (Brazil) were obtained through hydrodistillation. The chemical composition of the oils was determined using gas chromatography and mass spectrometry, which revealed the presence of 108 compounds representing 95.14%, 95.64%, 95.57%, 92.05%, 96.24% and 91.316% of the oils, respectively. All oils had an abundance of sesquiterpenes, except the oil from P. alatipetiolatum, which had a higher percentage of monoterpenes. The major components were α-eudesmol in the P. japurense (22.05%) and P. coariense (27.33%) oils, premnaspirodiene (32.26%) in the P. auriculifolium oil, caryophyllene oxide (28.69%) in the P. curtistilum oil, linalool (43.88%) in the P. alatipetiolatum oil and β-elemene (12.75%) in the P. brevesanum oil. Although the oils were composed of terpenes, the chemical analysis revealed qualitative and quantitative differences. This is the first report of the chemical composition of these six species of Piper that occur in the Amazonia biome in Brazil. © 2019 ACG Publications. All rights reserved

    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

    Pervasive gaps in Amazonian ecological research

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    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 understanding 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,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 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 underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities 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 organism 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 neglected 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 lost

    Diversity of mites in agroecosystems and testing to alternative control of the broad mite, Polyphagotarsonemus latus (Acari: Tarsonemidae), in the Manaus region, Amazonas

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    A Amazônia é tida como a região de maior biodiversidade do Planeta. No entanto, pouco se sabe a respeito da diversidade de ácaros plantícolas nesta região. Dentre estes ácaros estão espécies fitófagas, generalistas e predadoras. Este último grupo é de grande interesse, pois pode haver espécies promissoras para uso em programas de controle biológico de pragas. Já os fitófagos são indesejados devido ao dano que algumas espécies podem causar como é o caso do ácaro-branco Polyphagotarsonemus latus (Banks), o principal ácaro praga na região de Manaus, sobretudo em pimentão. Assim, o objetivo deste trabalho foi determinar a diversidade de ácaros associados às frutíferas nativas da região Amazônica e testar formas alternativas e sustentáveis para o controle do ácaro-branco em pimentão nesta região. Foram realizadas coletas no campus da Universidade Federal do Amazonas (UFAM), na fazenda Experimental da UFAM e no município de Anamã, Iranduba e Manacapurú. Os ácaros retirados de cada amostra foram montados, identificados e quantificados. Para o controle do ácaro-branco foram feitos testes com ácaros predadores nativos da região e com extratos aquoso de folha e inflorescência de Piper aduncum L. Foram coletadas 81 espécies de ácaros das famílias Tetranychidae, Tenuipalpidae, Tarsonemidae, Phytoseiidae e Ascidae. Nenhum dos predadores estudados mostrou-se eficiente para o controle do ácaro-branco, apresentando baixa sobrevivência e taxa de oviposição, quando alimentados com esta praga. Extratos aquosos a base de P. aduncum em altas cocentrações mostraram-se promissores para o controle de P. latus, sendo seletivo ao ácaro predador Amblyseius largoensis (Muma).The Amazon region is considered the most biodiverse on the planet. In however, little is known about the diversity of plants mites in this region. Among these mites are phytophagous species, generalist and predators. This latter group is of great interest because there may be promising species for use in biological control programs of pests. Since the phytophagous are unwanted because of the damage that some species can cause as is the case of broad mite Polyphagotarsonemus latus (Banks), the main mite pest in the Manaus region, especially in pepper. Thus, the objective was to determine the diversity mites associated with fruit native to the Amazon region and test alternative and sustainable ways to control the mite in peppers in this region. Collections were made on the campus of Universidade Federal do Amazonas-UFAM (Federal University of Amazon), in the experimental farm of UFAM and at the municipality of Anamã, Iranduba and Manacapuru. Mites removed from each sample were mounted, identified and quantified. To the broad mite control, were tested native predatory mite and aqueous extracts of leaf and inflorescence of Piper aduncum L. We collected 81 species of mites of the families Tetranychidae, Tenuipalpidae, Tarsonemidae, Phytoseiidae and Ascidae. None of the predators studied was efficient to control the mite, with low survival and oviposition rate when fed with this pest. Aqueous extracts the basis of P. aduncum in high cocentrações proved promising for the control of P. latus, being selective to predatory mite Amblyseius largoensis (Muma)

    Efficiency of the predatory mites Phytoseiulus fragariae and Neoseiulus californicus (Acari: Phytoseiidae) in the control of Tetranychus evansi and T. urticae (Acari: Tetranychidae) in Lycopersicon esculentum and Solanum americanum

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    O tomateiro (Lycopersicon esculentum Mill.) figura no cenário mundial como a principal hortaliça em volume industrializado e a segunda atividade hortícola, no que se refere à área cultivada e à importância econômica. A cultura do tomate é conhecida como uma atividade agrícola de alto risco, devido aos graves problemas fitossanitários que ocorrem durante todo seu ciclo. Dentre as principais pragas do tomateiro pode ser citado o ácaro Tetranychus evansi Baker e Pritchard. Este ácaro é encontrado nas Américas, África, Europa e, mais recentemente, na Ásia. No continente africano, esta praga ocasiona perdas de até 90% na produção.T. evansi tem se mostrado uma presa desfavorável para a maioria dos predadores estudados até recentemente. Encontra-se em andamento um projeto de controle biológico com intuito de localizar agentes eficientes para o controle de T. evansi, que possam ser introduzidos no continente africano. As buscas estão sendo realizadas em espécies de Solanaceae em regiões do continente sul americano que apresentam condições climáticas semelhantes às encontradas nos países africanos onde esta praga esta ocorrendo. Os ácaros predadores (Phytoseiidae) encontrados em associação com T. evansi naquelas avaliações foram Phytoseiulus longipes Evans, Phytoseiulus fragariae Denmark e Schicha e Neoseiulus californicus (McGregor), coletadas no município de Uruguaiana, Estado do Rio Grande do Sul. Estudos em laboratório e campo com populações de P. longipes apresentaram resultados bastante promissores no controle de T. evansi Nada se conhece, entretanto em relação ao potencial dos outros dois predadores como agentes de controle daquela praga. O objetivo do presente trabalho foi avaliar o potencial dos predadores P. fragariae e N. californicus, no controle biológico de T. evansi e T. urticae em solanáceas.Tomato (Lycopersicon esculentum Mill.) is the most important industrialized vegetable crop in the world, and the second horticultural activity in terms of cultivated area and economic importance. The tomato crop is known as an agricultural activity of high risk, due to phytosanitary problems during the entire cycle. Among the mite pests of tomato, Tetranychus evansi Baker and Pritchard is one of the most important in many countries. This mite has been found in the Americas, Africa, Europe and more recently, in Asia. In Africa, this pest causes losses of up to 90% in the tomato production. T. evansi is an unfavourable prey for the most common predatory mites studied until recently. In order to reduce the losses caused by T. evansi in África, a classical biological control program was initiated with the intention of identifying exotic natural enemies of T. evansi in South America that can be potentially introduced into Africa. The searches are being conducted on Solanaceae plants in areas of South America with similar climatic conditions of those where T. evansi is found in Africa. Three predatory mites (Phytoseiidae) were found associated with T. evansi in Uruguaiana-RS, Phytoseiulus longipes Evans, Phytoseiulus fragariae Denmark and Schicha and Neoseiulus californicus (McGregor). Laboratory and field studies with P. longipes presented promising results and demonstrated that this predator is a potential candidate agent against T. evansi. The potential of the two other predatory species against T. evansi is unknown. The objective of this study was to evaluate the potential of P. fragariae and N. californicus in the biological control of T. evansi and T. urticae in Solanaceae

    Efeito letal de extratos de piperáceas ao ácaro-vermelho-das-palmeiras, Raoiella indica: Acari, Tenuipalpidae

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    Since the introduction of the red palm mite, Raoiella indica, in Brazil, some control methods have been studied to suppress this pest, such as the quarantine, chemical, biological and plant extract control. This study aimed to evaluate the lethal potential of aqueous extracts of Piper aduncum, P. callosum, P. hostmannianum, P. marginatum and P. peltatum against R. indica. The residual contact action of the extracts applied by immersion at concentrations of 0, 5, 10, 15, 20, 25 and 30% was evaluated, and the action evaluated at three exposure periods, 24, 48 and 72 h. From the mortality data at the different concentrations and at each exposure period, corrected mortalities and lethal concentrations (LC25% and LC50%) of the piperaceous extracts for the R. indica population were determined. Only the extracts of P. aduncum, at 5% after 24 h of exposure, and P. callosum, in this same concentration at all times of exposure, did not present corrected mortality different from the control. The LC25% ranged from 0.99 to 13.02%, 1.29 to 7.89% and 1.82 to 7.69%, respectively, for the 24, 48 and 72 h exposure periods. Already the LC50%, respectively for the same exposure periods, ranged from 2.27 to 21.29%, 2.33 to 13.26% and 2.84 to 10.94%. The aqueous leaf extracts of the five species of piperaceous showed toxicological effect the R. indica population.Desde a introdução do ácaro-vermelho-das-palmeiras, Raoiella indica, no Brasil, diversos métodos de controle têm sido estudados para supressão desta praga, a exemplo dos métodos de controle quarentenários, químicos, biológicos e com extratos vegetais. O presente estudo objetivou avaliar o potencial letal de extratos aquosos de folha de Piper aduncum, P. callosum, P. hostmannianum, P. marginatum e P. peltatum sobre R. indica. Foi avaliada a ação residual de contato dos extratos, aplicados por imersão, nas concentrações de 0, 5, 10, 15, 20, 25 e 30%, sendo a ação avaliada em três períodos de exposição, 24, 48 e 72 h. A partir dos dados de mortalidade nas diferentes concentrações e em cada período de exposição foram determinadas as mortalidades corrigidas e as concentrações letais (CL25% e CL50%) dos extratos das piperáceas para a população de R. indica. Apenas os extratos de P. aduncum, a 5% após 24 h de exposição, e P. callosum, nesta mesma concentração em todos os tempos de exposição, não apresentaram mortalidade corrigida diferente do controle. As CL25% variaram de 0,99 a 13,02%, 1,29 a 7,89% e 1,82 a 7,69%, respectivamente, para os períodos de exposição de 24, 48 e 72 h. Já as CL50%, respectivamente para os mesmos períodos, variaram de 2,27 a 21,29%, 2,33 a 13,26% e 2,84 a 10,94%. Os extratos aquosos de folha das cinco espécies de piperáceas apresentaram efeito toxicológico sobre a população de R. indica
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