Comunidades de aranhas (Araneae) em cultivos de seringueira (Hevea brasiliensis Muell. Arg.) no Estado de São Paulo

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

Occurrence and geochemistry of metamafic rocks from the Forquilha Eclogite Zone, central Ceara (NE Brazil): geodynamic implications

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito do cultivo do mamoeiro (Carica papaya L.) em ambiente protegido sobre a ocorrência de ácaros fitófagos e moscas-brancas

O efeito do cultivo do mamoeiro em ambiente protegido foi estudado em três condições: sem cobertura e em dois telados construídos com tela de propileno branca, com malhas de 2 x 2 mm e 2 x 1 mm. Nessa área foram feitas avaliações na cultivar Baixinho de Santa Amália, contando-se o número de plantas com sintomas de ataque recente, para o ácaro branco Polyphagotarsonemus latus, com sintomas e presença de ácaros, para o ácaro rajado Tetranychus urticae e com presença de adultos ou ninfas nas folhas, no caso das moscas-brancas Trialeurodes sp., Bemisia tabaci biótipo B e uma terceira espécie não identificada. Para moscas-brancas, também foram realizadas contagens de ninfas e exúvias em laboratório. O cultivo em ambiente protegido favoreceu a sobrevivência e o desenvolvimento populacional das espécies estudadas, sendo que algumas possíveis causas são discutidas no texto. Considerando-se que o cultivo protegido pode ser uma boa alternativa para o controle de viroses, como o mosaico do mamoeiro, problema limitante para a cultura, estratégias de manejo de pragas nesses ambientes devem ser desenvolvidas, para viabilizar o seu uso.

Resistência de cultivares de videira ao ácaro-rajado Tetranychus urticae na região de Jales, estado de São Paulo

As videiras da região de Jales, Estado de São Paulo, têm sido intensamente atacadas pelo ácaro-rajado, Tetranychus urticae Koch. O presente trabalho teve por objetivo comparar cultivares de uva quanto à adequação como hospedeiras da espécie. em experimento de campo, naquele local, a ocorrência da praga, ao longo de 12 meses, foi acompanhada nas cultivares de uvas finas, Itália e Benitaka, e na cultivar de uva rústica, Niagara Rosada. No laboratório, a biologia de T. urticae foi estudada nessas três cultivares e na 'Redimeire'. Na cultivar Niagara Rosada, o ácaro-rajado apresentou menor fecundidade e menor sobrevivência, indicando a presença de mecanismos de resistência por antibiose. Além disso, houve maior tentativa de fuga dessa cultivar, sugerindo resistência por não preferência.

Distribution and importance of spiders inhabiting a Brazilian sugar cane plantation

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

Efeito da pulverização com turboatomizadores em diferentes condições operacionais no controle de ácaros em citros

Estudou-se o efeito das pulverizações de azocyclotin por turboatomizadores Jacto Arbus 2000/Export e Arbus 2000/850, sob diferentes condições operacionais, no controle do ácaro purpúreo, Panonychus citri (McGregor), e da leprose, Brevipalpus phoenicis (Geijskes); e de Arbus 2000/Export contra o ácaro da falsa ferrugem, Phyllocoptruta oleivora (Ashmead). Foram instalados três experimentos em pomares de citros (var. Valência) no período de 1994/95. O acaricida azocyclotin na dose 25 g i.a. / 100 litros d'água foi eficiente por 52 dias no controle de B. phoenicis e por 28 dias contra P. oleivora. Variações nas condições operacionais dos turboatomizadores não influenciaram no controle dos ácaros pragas. O produto azocyclotin pulverizado a 75% da dosagem comercial com 35 bicos do tipo JA-2 (Jacto), a 3,6 km/h e na pressão de 2070 kPa proporcionaram níveis de controle equivalentes aos obtidos com 100% da dosagem comercialmente recomendada desse acaricida, até 16 dias, quando aplicado com o turboatomizador Jacto Arbus 2000/Export no controle de P. citri.

Hálux valgo e pés planos: as forças plantares são iguais?

OBJETIVO: Este trabalho teve como objetivo estimar as forças plantares nos dedos dos pés de mulheres com hálux valgo e/ou pés planos. MÉTODOS: Trata-se de um estudo transversal envolvendo mulheres com hálux valgo e/ou pés planos confirmado através de análise radiográfica. Mediram-se as forças plantares, utilizando plataformas de forças. Coletaram-se estas forças com as mulheres descalças e em posição ereta, por três medidas sendo obtida uma média. Os dados foram adquiridos através da ponte amplificadora Spider 8 da HBM e analisados através do programa Catman®. Obtiveram-se as medidas de forças dos dedos de ambos os pés e as médias foram comparadas pelo teste t de Student segundo a presença de hálux valgo e pés planos; a associação entre essas deformidades foi estimada pelo teste exato de Fischer bicaudal, a significância estatística adotada foi alfa = 5%. RESULTADOS: Foram incluídas no estudo, vinte mulheres com presença ou não de hálux valgo. As forças médias encontradas mostraram-se maiores no 5º dedo em relação ao 1º dedo de ambos os pés (p< 0,05) em ambas as situações. CONCLUSÃO: Neste estudo encontraram-se, ao contrário de outros trabalhos, forças no 5º dedo maiores que no 1º em ambos os pés.

Bromeliad-living spiders improve host plant nutrition and growth

Although bromeliads are believed to obtain nutrients from debris deposited by animals in their rosettes, there is little evidence to support this assumption. Using stable isotope methods, we found that the Neotropical jumping spider Psecas chapoda (Salticidae), which lives strictly associated with the terrestrial bromeliad Bromelia balansae, contributed 18% of the total nitrogen of its host plant in a greenhouse experiment. In a one-year field experiment, plants with spiders produced leaves 15% longer than plants from which the spiders were excluded. This is the first study to show nutrient provisioning in a spider-plant system. Because several animal species live strictly associated with bromeliad rosettes, this type of facultative mutualism involving the Bromeliaceac may be more common than previously thought.

A natural combinatorial chemistry strategy in acylpolyamine toxins from Nephilinae orb-web spiders

The present study shows how nature combined a small number of chemical building blocks to synthesize the acylpolyamine toxins in the venoms of Nephilinae orb-web spiders. Considering these structures in four parts, it was possible to rationalize a way to represent the natural combinatorial chemistry involved in the synthesis of these toxins: an aromatic moiety is connected through a linker amino acid to a polyamine chain, which in turn may be connected to an optional tail. The polyamine chains were classified into seven subtypes (from A to G) depending on the way the small chemical blocks are combined. These polyamine chains may be connected to one of the three possible chromophore moieties: 2,4-dihydroxyphenyl acetic acid, or 4-hydroxyindole acetic acid, or even with the indole acetic group. The connectivity between the aryl moiety and the polyamine chain is usually made through an asparagine residue; optionally a tail may be attached to the polyamine chain; nine different types of tails were identified among the 72 known acylpolyamine toxin structures. The combinations of three chromophores, two types of amino acid linkers, seven sub-types of polyamine backbone, and nine options of tails results in 378 different structural possibilities. However, we detected only 91 different toxin structures, which may represent the most successful structural trials in terms of efficiency of prey paralysis/death.

Association of two new Coryphasia species (Araneae, Salticidae) with tank-bromeliads in southeastern Brazil: Habitats and patterns of host plant use

Two allopatric species of Coryphasia (Araneae: Salticidae), both described for the first time in this study, have been found associated with Bromeliaceae in distinct phytophysiognomies (e.g., inselbergs, highland forests and restingas) from southeastern Brazil. In this study, we investigated whether these salticids were associated specifically with bromeliads, and whether they used bromeliads of different species and sizes in distinct geographic regions. The Coryphasia species were rarely found outside bromeliads, occupied larger bromeliad species among those available, and were generally more frequent on bromeliads in open areas, such as inselbergs on mountain tops. The two Coophasia species were observed submerging in phytotelmata, possibly as an anti-predatory behavior. The patterns of spatial and microspatial distribution and the submergence behavior of these species were similar to those of other bromeliad-dwelling salticids, which suggests a convergence among spiders that live on bromeliads.

Winged leaf-cutting ants on nuptial flights used as transport by Attacobius spiders for dispersal

1. Sexuals of a leaf-cutting ant, Atta bisphaerica Forel, left their nest for nuptial flights in October to December.2. When leaving a nest, 53 of the 479 winged sexuals (or alates) observed (11.1%) carried up to three inquiline spiders of Attacobius luederwaldti.3. Spiders exclusively selected winged sexuals, not workers, and preferred females, indicating their expectation of the stronger flight ability of females. Neither these sexuals nor workers that appeared out of the nest on flight days attempted to remove or attack spiders on the body of alates.4. New qucens landing from their nuptial flight did not carry spiders, indicating that the spiders had left the ants in the sky to be dispersed by wind.5. No spiders were found in more than 100 incipient nests, which were estimated to be 2-3 months old. This suggests that the spiders jumped off the alate during mid-flight and dispersed on the wind to inhabit larger nests.

Geographic range, habitats, and host plants of bromeliad-living jumping spiders (Salticidae)

Although spiders are a very diverse group on vegetation, their associations with plants are poorly known. Some salticid species specifically use Bromeliaceae as host plants in some regions of South America. In this study, I report the geographic range of these spider-bromeliad associations, and whether the spiders inhabit particular bromeliad species and vegetation types, as well as open areas or interior of forests. Nine salticid species were found to be associated with up to 23 bromeliad species in cerrados (savanna-like vegetation), semideciduous and seasonal forests, coastal sand dune vegetation, restingas, inselbergs, highland forests, chacos, and rain forests at 47 localities in Brazil, Paraguay, Bolivia, and Argentina. Some species were typically specialists, inhabiting almost exclusively one bromeliad species over a large geographic range (e.g., Psecas chapoda on Bromelia balansae), whereas others were generalists, occurring on up to 7-8 bromeliad species (e.g., Psecas sp., Eustiromastix nativo, and Coryphasia sp. 1). The regional availability of bromeliad species among habitats may explain this pattern of host plant use. More jumping spiders were found on bromeliads in open areas than on bromeliads in the interior of forests. These results show that several jumping spider species may be strictly associated with the Bromeliaceae in the Neotropics. This is one of the few studies to show host-specific associations for spiders on a particular plant type over a wide geographic range.

Associations of spiders of the genus Peucetia (Oxyopidae) with plants bearing glandular hairs

Two common South American species of lynx spiders, Peucetia rubrolineata and P. flava (Oxyopidae), were surveyed on three localities in southeastern Brazil to determine plant choice. Both species were found to be associated with plants bearing glandular trichomes. A literature review and complementary data show that ten Peucetia species are associated with up to 55 plant species bearing glandular trichomes in at least 20 distinct vegetation types (phytophysiognomies) in more than 36 localities in the Neotropical, Neartic, Afrotropical, and Paleartic regions. The main plant families used by the spiders were Solanaceae, Asteraceae, and Melastomataceae. The specialization of the Peucetia species for plants bearing glandular trichomes may have evolved because insects adhered to these sticky structures may be used as prey by the spiders.

Cytogenetical characterization of six orb-weaver species and review of cytogenetical data for Araneidae

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

ANTI-HERBIVORE PROTECTION BY MUTUALISTIC SPIDERS and THE ROLE of PLANT GLANDULAR TRICHOMES

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