Natural Occurrence and Ecology of Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) in Cotton Plantations with Insecticides Spraying in Minas Gerais State, Brazil

Pest damage is one of the greatest problems in cotton production in the world. The objective of this study was to assess the natural occurrence, parasitism rate, number of adults ofTrichogramma emerged and coexistence with predators species in cotton plantations with insecticide spraying in Brazil. Parasitoids were collected in two areas of two-hectares each with the Dp 4049 and Delta Opal cotton varieties, using 12.0 x 2.5 cm pieces of white cards with an average of 3.000 Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs each. The predation percentage of A. kuehniella eggs in the field and parasitism occurrence was estimated based on the cards with eggs of this prey brought from the field. All parasitoids obtained were identified as Trichogramma pretiosum (Riley) (Hymenoptera: Trichogrammatidae). The predators collected were identified as belonging to the families Chrysopidae (Neuroptera), Coccinelidae (Coleoptera) and Sirphidae (Diptera). The average number of eggs parasitized per cardboard, during the cycle of this culture was 16.34 ± 5.1 in the area with Dp-4049 and 23.38 ± 4.3 in that with Delta opal. The predation average during the cycle of this culture was 42.58 ± 3.8 e 35.58 ± 2.9% in these areas, respectively. It is necessary to preserve and to increase the performance of T. pretiosum in cotton plantations

Quality control of Trichogramma atopovirilia and Trichogramma pretiosum (Hym.: Trichogrammatidae) adults reared under laboratory conditions

The objective of this work was to assess the flight capacity, parasitism and emergence of Trichogramma atopoviriliaand two strains of T. pretiosum (Hymenoptera: Trichogrammatidae) (L1 and L2). The flight capacity of these species was assessed in test units consisting of a plastic PVC cylinder with a rigid transparent plastic circle on the upper part and an extruded polystyrene disk closing its bottom. A tube was placed in each test unit containing a card with 300 Anagasta kuehniella (Lepidoptera: Pyralidae) eggs parasitised by Trichogramma. These cards were assessed to determine the parasitism rate and adult emergence of these natural enemies. T. atopovirilia and T. pretiosum L1 presented adequate flight capacity and parasitism, in addition to high percentages of adults emerged

FISIOLOGIA DA GERMINAÇÃO DE SEMENTES DA Annona squamosa L., FRUTA-DO-CONDE

A germinação das sementes é um processo que envolve a expressão coordenada de vários genes que irão suportar a retomada do crescimento do embrião, até então num estado latente. Procurando investigar o programa metabólico durante a germinação de sementes, foi realizado o presente trabalho utilizando como modelo biológico sementes de fruta-do-conde (Annona squamosa), por apresentar conteúdos significativos de amido e lipídios, as principais substâncias de reserva da maioria das sementes. O experimento foi conduzido em condições de laboratório, com as sementes colocadas para germinar em caixa de areia, tendo sido retiradas amostras aos 0, 10, 20, 30, 40, 50 e 60 dias de germinação. Nessas sementes foram analisados os conteúdos de amido, lipídios e proteínas, as atividades das isoformas invertásicas, da sintase da sacarose (SUSY), da a-amilase e da isocitrato liase. Os resultados obtidos suportam a hipótese do programa metabólico durante a germinação, com variações nas atividades das enzimas avaliadas acopladas à retomada do desenvolvimento do embrião

Diversidade e análise faunística de crisopídeos (Neuroptera: Chrysopidae) em fragmento de floresta estacional semidecidual em Três Pontas, Minas Gerais

O objetivo deste estudo foi avaliar a diversidade de espécies de crisopídeos em Floresta Estacional Semidecidual localizada em Três Pontas, Estado de Minas Gerais. A captura ativa foi realizada com rede entomológica confeccionada com tecido voil e armadilhas contendo melaço de cana-de-açúcar a 10% como fonte atrativa. As coletas foram realizadas semanalmente através de captura ativa no período de 13 de setembro de 2008 a 05 de setembro de 2009, e duas coletas com armadilhas atrativas em cada estação do ano. As coletas com rede entomológica foram iniciadas as 7:00 h e finalizadas as 17:00 h. Após esse horário, nas datas determinadas, foram distribuídas as armadilhas atrativas, que eram recolhidas no outro dia até as 7:00 h. Os insetos capturados foram montados em alfinetes entomológicos, etiquetados, triados e identificados. Plantas que tiveram alta concentração de crisopídeos foram coletadas, preparadas exsicatas e encaminhadas a especialista para identificação. Foram capturados 1.467 crisopídeos, distribuídos em 33 espécies, pertencentes as tribos Chrysopini e Leucochrysini. A espécie de maior ocorrência foi Ceraeochrysa tucumana (Navás, 1919), tendo a presença relatada em todas as amostragens. Não foi encontrado diferença entre os horários de coleta para os gêneros de crisopídeos. Nas coletas noturnas, foram capturados seis indivíduos, pertencentes as espécies Leucochrysa (Nodita) vignisi Freitas & Penny, 2001; Ceraeochrysa achillea Freitas e Penny, 2009; Chrysopodes spinella (Adams e Penny, 1987) e C. tucumana. Foi possível verificar associação entre espécies de crisopídeos com plantas do gênero CaseariaThe objective of this work was to study the diversity and faunistic analysis of lacewings species in Semideciduous Forest located in Três Pontas, southern Minas Gerais State, Brazil. Active capture was performed with an sweep net made of cheesecloth and traps with molasses cane sugar to 10% as attractive. Samples were weekly with active collected in period from 13/IX/2008 to 05/IX/2009 and two collections with attractive traps in each season. Sampling insect nets were opened at 7:00 pm and finished 17:00 h am. After this time, on certain dates, were distributed attractive traps, which were collected the next day until 7:00 pm. The insects were mounted on entomological pins, labeled, sorted and identified. Plants that have high concentrations of lacewings were collected, prepared and dried specimens sent to a specialist for identification. 1,467 lacewings were captured, distributed in 33 species belonging to the tribes Chrysopini and Leucochrysini. The species most frequent was Ceraeochrysa tucumana (Navás, 1919) and reported presence in all the samples. No difference was found between sampling times for the genus of Chrysopidae. In nocturnal collections were captured six individuals of the species Leucochrysa (Nodita) vignisi Freitas & Penny, 2001; Ceraeochrysa achillea Freitas and Penny, 2009; Chrysopodes Spinella (Adams and Penny, 1987) and C. tucumana. There was an obvious association between species of lacewings with plants of the genus CaseariaCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Assessment of Trichogramma species (Hymenoptera: Trichogrammatidae) for biological control in cassava (Manihot esculenta Crantz)

Cassava is the sixth most important crop in the world, and it is attacked by many pests, such as Erinnyis ello (L.) (Lepidoptera: Sphingidae). This lepidopteran pest has natural enemies that can efficiently control its population, such as Trichogramma spp. (Hymenoptera: Trichogrammatidae). The objective of this research was to assess the flight capacity, parasitism and emergence of Trichogramma pretiosum, T. marandobai and T. demoraesi and to select the most efficient species among them for biological control programs. The flight capacity of these species was assessed in test units consisting of a plastic PVC cylinder with a rigid, transparent plastic circle on the upper portion of the cylinder and an extruded polystyrene disk to close the bottom of the cylinder. A tube was placed in each test unit containing a card with 300 Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs that had been parasitised by Trichogramma. These cards were later assessed to determine the parasitism rate and adult emergence of these natural enemies. Trichogramma pretiosum presented the highest flight capacity (68 ± 5%), parasitism (74 ± 2%) and percentage of adults emerged (91 ± 3%) in the laboratory, making this species suitable for mass rearing and release in biological control programs

Assessment of Trichogramma species (Hymenoptera: Trichogrammatidae) for biological control in cassava (Manihot esculenta Crantz)

Cassava is the sixth most important crop in the world, and it is attacked by many pests, such as Erinnyis ello (L.) (Lepidoptera: Sphingidae). This lepidopteran pest has natural enemies that can efficiently control its population, such as Trichogramma spp. (Hymenoptera: Trichogrammatidae). The objective of this research was to assess the flight capacity, parasitism and emergence of Trichogramma pretiosum, T. marandobai and T. demoraesi and to select the most efficient species among them for biological control programs. The flight capacity of these species was assessed in test units consisting of a plastic PVC cylinder with a rigid, transparent plastic circle on the upper portion of the cylinder and an extruded polystyrene disk to close the bottom of the cylinder. A tube was placed in each test unit containing a card with 300 Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs that had been parasitised by Trichogramma. These cards were later assessed to determine the parasitism rate and adult emergence of these natural enemies. Trichogramma pretiosum presented the highest flight capacity (68 ± 5%), parasitism (74 ± 2%) and percentage of adults emerged (91 ± 3%) in the laboratory, making this species suitable for mass rearing and release in biological control programs.A mandioca é a sexta cultura mais importante no mundo, sendo atacada por diversas pragas, incluindo Erinnyis ello (Linnaeus) (Lepidoptera: Sphingidae). Este lepidóptero apresenta inimigos naturais que podem controlar de forma eficiente sua população, destacando os parasitoides oófagos Trichogramma spp. (Hymenoptera: Trichogrammatidae). O objetivo deste trabalho foi avaliar Trichogramma pretiosum, T. marandobai e T. demoraesi quanto à sua capacidade de parasitismo, emergência e voo, visando selecionar a espécie mais eficiente para programas de controle biológico. Os parâmetros biológicos foram avaliados em unidades teste, consistindo de um cilindro de PVC com um circulo de plástico rígido e transparente no topo e um disco de poliestireno vedando a parte inferior. Um tubo de ensaio contendo 300 ovos de Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) parasitados por Trichogramma foi colocado no interior da unidade. Trichogramma pretiosum apresentou maior capacidade de voo (68 ± 5%) e porcentagens de parasitismo (74 ± 2%) e emergência de adultos (91 ± 3%) em laboratório, sendo indicado para criação e liberação em programas de controle biológico

Natural Occurrence and Ecology of Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) in Cotton Plantations with Insecticides Spraying in Minas Gerais State, Brazil

Pest damage is one of the greatest problems in cotton production in the world. The objective of this study was to assess the natural occurrence, parasitism rate, number of adults ofTrichogramma emerged and coexistence with predators species in cotton plantations with insecticide spraying in Brazil. Parasitoids were collected in two areas of two-hectares each with the Dp 4049 and Delta Opal cotton varieties, using 12.0 x 2.5 cm pieces of white cards with an average of 3.000 Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs each. The predation percentage of A. kuehniella eggs in the field and parasitism occurrence was estimated based on the cards with eggs of this prey brought from the field. All parasitoids obtained were identified as Trichogramma pretiosum (Riley) (Hymenoptera: Trichogrammatidae). The predators collected were identified as belonging to the families Chrysopidae (Neuroptera), Coccinelidae (Coleoptera) and Sirphidae (Diptera). The average number of eggs parasitized per cardboard, during the cycle of this culture was 16.34 ± 5.1 in the area with Dp-4049 and 23.38 ± 4.3 in that with Delta opal. The predation average during the cycle of this culture was 42.58 ± 3.8 e 35.58 ± 2.9% in these areas, respectively. It is necessary to preserve and to increase the performance of T. pretiosum in cotton plantations