Biological aspects of Dirphia moderata (Lepidoptera: Saturniidae) on Eucalyptus cloeziana and Psidium guajava

An egg mass of Dirphia moderata Bouvier was collected around a branch of Eucalyptus cloeziana to register the occurrence and to study the biological aspects of this species fed with leaves of E. cloeziana or P. guajava at 25 ± 2º C, relative humidity of 60 ± 10 percent and photo phase of 12 h. The duration and viability of the larva stage of D. moderata was 56.01 days and 80.00 percent and 55.79 days and 72.5 percent for its caterpillars fed with the first and second host plants, respectively. The duration (days) and viability ( percent) of the pupae stage of this insect were 37.64 and 87.00 fed with E. cloeziana and 49.93 and 87.75 with P. guajava, respectively. The average longevity (days) was 6.79 and 8.85 for males and 10.48 and 10.09 for females with E. cloeziana and P. guajava, respectively. Each female of D. moderata laid 121.71 and 112.00 eggs with an incubation period (days) of 18.14 and 17.79 and viability ( percent) of 75.0 and 70.0 with the first and the second hosts, respectively.

Postura de Dirphia moderata Bouvier, 1919 (Lepidoptera: Saturniidae) foi coletada ao redor de um ramo de Eucalyptus cloeziana na área experimental do Laboratório de Entomologia Florestal da Universidade Federal de Viçosa, em Viçosa, Minas Gerais. O objetivo foi registrar a ocorrência e estudar aspectos biológicos de D. moderata alimentada com folhas de E. cloeziana ou Psidium guajava na temperatura de 25 ± 2º C, umidade relativa de 60 ± 10 por cento e fotofase de 12 horas. A duração e a viabilidade larval foram de 56,01 dias e 80,00 por cento e de 55,79 dias e 72,50 por cento para lagartas de D. moderata alimentadas com E. cloeziana ou Psidium guajava, respectivamente. A duração (dias) e a viabilidade ( por cento) do estágio de pupa foram de 37,64 e 87,00 para este inseto com E. cloeziana e de 49,93 e 87,75 com P. guajava, respectivamente. A longevidade média (dias) foi de 6,79 e 8,85 para machos e de 10,48 e 10,09 para fêmeas desse inseto com E. cloeziana e P. guajava, respectivamente. Cada fêmea de D. moderata depositou 121,71 e 112,00 ovos com período de incubação (dias) de 18,14 e 17,79 e viabilidade ( por cento) de 75,0 e 70,0 com essas plantas hospedeiras, respectivamente.

Actividades enzimáticas en aislamientos bacterianos de tractos digestivos de larvas y del contenido de pupas de Automeris zugana y Rothschildia lebeau (Lepidoptera: Saturniidae)

Enzymatic activities of bacteria isolated from the digestive tract of caterpillars and the pupal content of Automeris zugana and Rothschildia lebeau (Lepidoptera: Saturniidae). The enzymatic activities of bacteria isolated from the digestive tracts of caterpillars and the pupal contents of Automeris zugana and Rothschildia lebeau was studied. This digestive tract represents an extreme microenvironment due to its high pH and presence of antimicrobial substances secreted by the insect or derived from ingested plant tissue. At the same time, it contains large amounts of nutrient-rich food, for which microbes may compete among themselves and with the caterpillar. There is little information about the microbiota associated with tropical caterpillar guts, although bacteria from different genera have been isolated from gut and pupae samples. The study of the enzymatic activities generated by these organisms constitutes a starting point to understand their metabolic and physiological relationships with their hosts, and to find enzymes that have potential biotechnological applications. In this study we evaluated several enzymatic activities in two collections of bacteria isolated from caterpillar guts and pupae of the tropical lepidopteran species A. zugana and R. lebeau. Bacteria grown under aerobic conditions were tested for an array of enzymes, including gelatinases, caseinases, lipases, esterases, cellulases, xylanases, amylases and chitinases. Both collections displayed similar patterns of enzymatic activity. No isolate showed activity for all enzymatic tests, but as a whole, at least some bacteria in each collection were able to degrade each substrate tested. Isolates with the same taxonomic identification obtained from caterpillar guts and pupae had almost the same enzymatic activities. In both collections, it was possible to group bacterial isolates according to their enzyme activity pattern. In addition to a heterogeneous ensemble of isolates exhibiting two or less enzymatic activities, there were two groups with at least five activities that showed an apparent specialization for the substrates they were able to use. The first consisted exclusively of isolates of the family Enterobacteriaceae, which were positive for lipolytic and chitinolytic activities, but completely lacked amylasic, cellulolytic and xylanolytic activities. The second group, composed mainly of Gram-positive rods, exhibited the opposite pattern: they were positive for amylasic, cellulolytic and xylanolytic activities, lacked chitinolytic activity and had few isolates with lipolytic activity. This work forms the foundation for future research to explore the biotechnological potential of bacterial isolates from caterpillar guts. Rev. Biol. Trop. 55 (2): 401-415. Epub 2007 June, 29.

El tracto digestivo de orugas constituye un microambiente extremo, debido a su elevado pH y presencia de sustancias antimicrobianas secretadas por el insecto o derivadas del tejido vegetal ingerido. Al mismo tiempo, el intestino alberga gran cantidad de alimento, por el cual los microorganismos presentes podrían competir entre sí y con su hospedero. Existe poca información sobre la microbiota asociada con el intestino de orugas tropicales, aunque se ha demostrado la presencia de bacterias de diversos géneros tanto en el intestino como en el interior de pupas. El estudio de las actividades enzimáticas de estos microorganismos constituye un punto de partida en la comprensión de la posible relación metabólica y fisiológica que establecen con sus hospederos, a la vez que permite investigar enzimas con potenciales aplicaciones biotecnológicas. En este trabajo se evaluó la presencia de actividades gelatinolítica, caseinolítica, esterásica, lipolítica, quitinolítica, amilásica, celulolítica y xilanolítica en dos colecciones de aislamientos bacterianos provenientes de tractos digestivos de orugas y de pupas de los lepidópteros Automeris zugana y Rothschildia lebeau. Se utilizaron ensayos bioquímicos tradicionales para detectar enzimas secretadas en condiciones aerobias, en las que ambas colecciones exhibieron un comportamiento enzimático similar. Ningún aislamiento produjo un resultado positivo en todas las pruebas, pero como conjunto ambas colecciones fueron capaces de utilizar todos los sustratos evaluados. Los aislamientos obtenidos de pupas presentaron prácticamente las mismas actividades que sus homólogos provenientes de intestinos. En ambas colecciones fue posible agrupar los aislamientos de acuerdo con su patrón de producción de enzimas. Además de un conjunto heterogéneo de aislamientos poco activos (dos o menos actividades), se destacan dos grupos muy activos (al menos cinco actividades), que manifiestan una aparente especialización en los sustratos que utilizan. El primero de ellos está constituido exclusivamente por miembros de la familia Enterobacteriaceae, los cuales exhibieron un alto porcentaje de positividad en actividades lipolítica y quitinolítica, pero no demostraron la expresión de las actividades amilásica, celulolítica ni xilanolítica. El segundo grupo, formado en su gran mayoría por bacilos Gram-positivos, presenta la situación opuesta: alta positividad en actividades amilásica, celulolítica y xilanolítica, no detección de actividad quitinolítica y pocos aislamientos con actividad lipolítica. Este trabajo pretende ser la base de futuras investigaciones que exploren el potencial biotecnológico de aislamientos bacterianos provenientes del tracto digestivo de orugas.

Ultraestructura de los huevos de dos mariposas nocturnas de Chile: Ormiscodes socialis y Polythysana cinerascens (Lepidoptera: Saturniidae) / Egg ultrastructure in two Chilean moths: Ormiscodes socialis and Polythysana cinerascens (Lepidoptera: Saturniidae)

The structure and ultra-structure of the eggs from Ormiscodes socialis (Feisthamel) and Polythysana cinerascens (Philippi) are described, considering shape, size, coloring when recently laid, oviposition type and aeropiles (quantity, distribution and proportion) in the micropilar area, among others. The ultra-structure is shown for primary cells, secondary cells, aeropiles and micropiles. A comparative table of the eggs of these species is presented and includes the previously described eggs of Adetomeris microphthalma (Philippi). Myoschilos oblonga Ruiz y Pavón (Santalaceae) is recorded as a new host for P. cinerascens.

Se describe la estructura y ultraestructura de los huevos de las especies Ormiscodes socialis (Feisthamel) y Polythysana cinerascens (Philippi), considerando la forma, tamaño, color, tipo de ovipostura, y aeropilas (cantidad, distribución y proporción) en el área micropilar, entre otros. La ultraestructura es mostrada a través de las celdas primarias, celdas secundarias, aeropilas y micropilas; además se incluye a la especie ya descrita Adetomeris microphthalma (Philippi) y se confecciona un cuadro comparativo para los huevos de estas especies. Se registra como nuevo hospedero de P. Cinerascens a Myoschilos oblonga Ruiz y Pavón (Santalaceae).

Novo registro de Lepidoptera na cultura do milho no Brasil / New record of Lepidoptera on corn crop in Brazil

No mês de abril de 2001 foram encontradas larvas de Pseudautomeris luteata (Walker) (Lepidoptera: Saturniidae) alimentando-se de folhas de milho (Zea mays L.) no município de Piracicaba, estado de São Paulo. Exemplares adultos foram depositados na coleção de insetos do Departamento de Entomologia, Fitopatologia e Zoologia Agrícola, Escola Superior de Agricultura Luis de Queiroz, USP, Piracicaba.

Larvae of Pseudautomeris luteata (Walker) (Lepidoptera: Saturniidae) were found in April of 2001 feeding on leaves of corn (Zea mays L.) in Piracicaba, State of São Paulo, Brazil. Adult specimens were deposited in the insects collection of the Departmento de Entomologia, Fitopatologia e Zoologia, of the Escola Superior de Agricultura Luis de Queiroz, USP, Piracicaba, Brazil.