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Item Himenópteros associados a Solanum gilo raddi (Solanaceae)(Revista Brasileira de Zoologia, 1997-12) Picanço, Marcelo; Casali, Vicente Wagner Dias; Oliveira, Ivênio Rubens de; Leite, Germano Leão DemolinThe Hymenoptera fauna associated to Solanum gilo was studied. There were 21 species of Hymenoptera from eight families. It was observed Homalotylus flaminus (Dalman, 1820) (Encyrtidae) parasiting the adults of Cycloneda sanguinea Linnaeus, 1763 (Coleoptera, Coccinellidae) and Chalcididae parasiting caterpillars of Mechanitis pofymnia casabranca Haensch, 1905 (Lepidoptera, Nymphalidae, Ithomiinae, Sthomiinae). Vespidae were observed preying both M. pofymnia casabranca and Diabrotica speciosa Germar, 1824 (Coleoptera, Chrysomelidae) adults. Halictidae, Andrenidae and Anthophoridae, were observed visiting flowers and Trigona spinipes (Fabricius, 1793) (Apidae) attacking fruits and stem ápices. The most abundant Hymenoptera were Formicidae; Cremalogaster sp. and Camponotus rufipes (Fabricus, 1775) were observed in protocooperation relation with Homoptera, the main cause of plant mortality was Solenopsis saevissima (Smith, 1855). Higher population density of Formicidae occurred on the final phase of cultivation, when there were high insolation and temperature and low pluvial precipitations.Item Whitefly population dynamics in okra plantations(Pesquisa Agropecuária Brasileira, 2005-01) Picanço, Marcelo; Jham, Gulab Newandram; Moreira, Márcio Dionízio; Leite, Germano Leão DemolinThe control of whitefly Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) on okra (Abelmoschus esculentus L.) consists primarily in the use of insecticides, due to the lack of information on other mortality factors. The objective of this study was to evaluate the spatial and temporal population dynamics of the whitefly B. tabaci biotype B on two successive A. esculentus var. "Santa Cruz" plantations. Leaf chemical composition, leaf nitrogen and potassium contents, trichome density, canopy height, plant age, predators, parasitoids, total rainfall and median temperature were evaluated and their relationships with whitefly on okra were determined. Monthly number estimates of whitefly adults, nymphs (visual inspection) and eggs (magnifying lens) occurred on bottom, middle and apical parts of 30 plants/plantation (one leaf/plant). Plants senescence and natural enemies, mainly Encarsia sp., Chrysoperla spp. and Coccinellidae, were some of the factors that most contributed to whitefly reduction. The second okra plantation, 50 m apart from the first, was strongly attacked by whitefly, probably because of the insect migration from the first to the second plantation. No significant effects of the plant canopy on whitefly eggs and adults distribution were found. A higher number of whitefly nymphs was found on the medium part than on the bottom part.Item Bemisia tabaci, Brevicoryne brassicae and Thrips tabaci abundance on Brassica oleracea var. acephala(Pesquisa Agropecuária Brasileira, 2005-03) Picanço, Marcelo; Moreira, Márcio Dionízio; Jham, Gulab Newandram; Leite, Germano Leão DemolinKale Brassica oleracea var. acephala is attacked by whitefly Bemisia tabaci, aphid Brevicoryne brassicae and Thrips tabaci. One of the main reasons for extensive insecticide application is the lack of information about factors that control insect population. The objectives of this study were to investigate the relationships between predators and parasitoids, organic compound leaves, levels of leaf nitrogen and potassium, total rainfall, relative humidity, sunlight and median temperature on the abundance of whitefly, aphid, and thrips in kale genotype "Talo Roxo". The beating tray method, direct counting and magnifying lens were used to estimate the number of these pests, predators and parasitoids. Median temperature, sunlight and relative humidity correlated to the amount of leaf nonacosane, which in turn was associated with aphids population increase. A tendency in the reduction of aphids and thrips populations with increase in total rainfall was observed. The whitefly can be a harmful pest in kale producing regions of higher temperature and smaller rainfall. In regions which present moderate temperature, where there is a high incidence of aphids, genotype with low leaf wax content should be chosen. Natural enemies, especially the parasitoid Adialytus spp., can control agents of the aphids population in kale.Item Efeito de tricomas, aleloquímicos e nutrientes na resistência de Lycopersicon hirsutum à traça-do-tomateiro(Pesquisa Agropecuária Brasileira, 1999-11) Leite, Germano Leão Demolin; Picanço, Marcelo; Azevedo, Aristéa Alves; Gonring, Alfredo Henrique RochaEstudos foram conduzidos com o objetivo de verificar o efeito de tricomas, aleloquímicos e nutrientes nas folhas de partes do dossel das plantas na resistência de Lycopersicon hirsutum à traça- do-tomateiro, Tuta absoluta (Lepidoptera: Gelechiidae). Foram quantificados os teores de 2-tridecanona (2-TD), 2-undecanona (2-UD), N, P, K, Ca e Mg, densidade e tipos de tricomas e tamanho das folhas nos terços apical, mediano e basal do dossel de plantas de L. hirsutum e de L. esculentum e estudaram- se os efeitos destes fatores sobre características biológicas de T. absoluta. Observou-se elevação no teor de 2-TD da base para o ápice do dossel. Não se detectou diferença significativa quanto ao número de ovos de T. absoluta ao longo do dossel de L. hirsutum, constatando-se em L. esculentum maior oviposição nos terços apical e mediano do que no basal. As folhas do terço apical de L. hirsutum apresentaram maior efeito deletério sobre as larvas de traça.Item Qualidade da semente e senescência de genótipos de soja sob dois níveis de infestação de percevejos (Pentatomidae)(Pesquisa Agropecuária Brasileira, 1999-08) Lustosa, Paulo Rogério; Zanuncio, José Cola; Leite, Germano Leão Demolin; Picanço, MarceloEste trabalho objetivou estudar a resistência de duas linhagens de soja, do programa de melhoramento do sabor da Universidade Federal de Viçosa, MG, cultivadas sob dois níveis de infestação de percevejos, em comparação com três cultivares de soja. Os genótipos estudados foram: CR-1, CR-3, Cristalina (linhagem paterna), Davis (padrão de suscetibilidade) e IAC-100 (padrão de resistência). CR-1, CR-3, Davis e Cristalina, sob baixa infestação, produziram porcentagens de sementes normais semelhantes entre si (57%), e inferiores às de IAC-100 (77%). Sob alta infestação, CR-1, CR-3 e Cristalina produziram percentagens de sementes normais semelhantes entre si (22%) e inferiores às de Davis (43%) e IAC-100 (59%). Todos os genótipos apresentaram baixo grau de retenção foliar (menos que 6%) quando cultivados sob baixa infestação, mas sob alta infestação, a CR-1 e IAC-100 apresentaram menores porcentagens de retenção foliar (menos que 5%), seguida por Davis e CR-3 (6-20%) e Cristalina (21-40%). CR-1, IAC-100 e Davis não apresentaram plantas com caule verde sob baixa infestação, ao contrário do que foi registrado com CR-3 (3,6%) e Cristalina (11%). IAC-100, CR-1 e Davis apresentaram menores porcentagens de plantas com caule verde (6,4, 10,3 e 18,3%, respectivamente) que CR-3 (64,8%) e Cristalina (77,3%).Item Within tree distribution of a gall-inducing Eurytoma (Hymenoptera, Eurytomidae) on Caryocar brasiliense (Caryocaraceae)(Revista Brasileira de Entomologia, 2009-12) Leite, Germano Leão Demolin; Veloso, Ronnie Von dos Santos; Silva, Farley Willian Souza; Guanabens, Rafael Eugênio Maia; Fernandes, G. WilsonFor the first time, we identified the insect herbivore that induces one of the most conspicuous galls on the leaves of Caryocar brasiliense Camb. (Caryocaraceae), a widespread, typical cerrado woody plant of large economic importance. The gall inducing organism is a new and undescribed species of Eurytoma sp. (Hymenoptera, Eurytomidae). Furthermore, we recorded its spatial distribution within C. brasiliense trees. More Eurytoma galls were found on the eastern tree slope, followed the southern and northern slopes. More galls were found in the interior of the tree crown, i.e., on the proximal portion of the stems compared to the terminal portion. At the leaf level, more galls were found on the median region compared to the distal or proximal, perhaps due to the lower trichome density found in there. Leaf colonization by Eurytoma sp. may initiate at the leaf margin but after colonization reaches 50% the central portion starts to be colonized.Item Parasitism Capacity of Trichogramma pretiosum and Trichogramma acacioi (Hym.: Trichogrammatidae) on eggs of Sitotroga cerealella (Lep.: Gelechiidae)(Brazilian Archives of Biology and Technology, 2008-11) Pratissoli, Dirceu; Zanuncio, José Cola; Vianna, Ulysses Rodrigues; Andrade, Josimar Souza; Zinger, Fernando Domingo; Alencar, João Rafael de Conte Carvalho de; Leite, Germano Leão DemolinThe objective of this work was to evaluate the parasitism capacity of Trichogramma pretiosum Riley and T. acacioi Brun, Moraes and Soares (Hymenoptera: Trichogrammatidae) in eggs of the alternative host Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae) aiming to use both species in biological control programs of Nipteria panacea Tierry-Mieg (Lepidoptera: Geometridae). The parasitism rhythm and total parasitism of these parasitoid species were affected by the temperature with higher values during the first 24 h of their life. Parasitism period was longer for T. pretiosum and T. acacioi at the lowest temperature.Item Factors affecting herbivory of Thrips palmi (Thysanoptera: Thripidae) and Aphis gossypii (Homoptera: Aphididae) on the eggplant (Solanum melongena)(Brazilian Archives of Biology and Technology, 2006-05) Picanço, Marcelo; Zanuncio, José Cola; Ecole, Carvalho Carlos; Leite, Germano Leão DemolinThe objective of this study was to evaluate effects of total rainfall, mean temperature, natural enemies, chemical composition of leaves, levels of nitrogen and potassium on leaves and density of leaf trichomes on attack intensity of Thrips palmi Karny (Thysanoptera: Thripidae) and Aphis gossypii (Glover) (Homoptera: Aphididae) on plantations of the eggplant (Solanum melongena) in two regions of Minas Gerais, Brazil. Higher numbers of A. gossypii/leaf and T. palmi/leaf were observed in plantations of this eggplant in the Municipalities of Viçosa and Guidoval, respectively. Guidoval had a rainy and hotter weather than Viçosa. T. palmi was almost positivelly correlated with rainfall (r= 0.49, P= 0.0538) while A. gossypii seemed to be more affected by mean temperature (r= -0.31; P= 0.1134). Higher number of aphids in eggplants in Viçosa than in Guidoval could be explained by the higher number of natural enemies such as Adialytus spp. (Hymenoptera: Braconidae), Cycloneda sanguinea (L.) and Exochomus bimaculosus Mulsant (Coleoptera: Coccinellidae) and Chrysoperla spp. (Neuroptera: Chrysopidae) in this municipality. However, only Adialytus spp. was significativelly correlated with aphid populations. Higher number of T. palmi in eggplant plantations of Guidoval than in Viçosa could be due to the absence of its possible Eulophidae parasitoid in the first municipality. The spiders were significativelly correlated with this pest in both municipalities.Item Quality control of Trichogramma atopovirilia and Trichogramma pretiosum (Hym.: Trichogrammatidae) adults reared under laboratory conditions(Brazilian Archives of Biology and Technology, 2012-03) Zanuncio, José Cola; Soares, Marcus Alvarenga; Leite, Germano Leão Demolin; Sá, Veríssimo Gibran Mendes de; Ferreira, Cleidson Soares; Rocha, Silma Leite; Pires, Evaldo Martins; Serrão, José EduardoThe 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.Item Seasonal damage caused by herbivorous insects on Caryocar brasiliense (Caryocaraceae) trees in the Brazilian savanna(Revista Colombiana de Entomología, 2018-01) Veloso, Ronnie Von Dos Santos; Zanuncio, José Cola; Ferreira, Paulo Sergio Fiúza; Serrão, José Eduardo; Ramalho, Francisco de Souza; Almeida, Chrystian Iezid Maia; Leite, Germano Leão DemolinCaryocar brasiliense (Caryocaraceae) trees have a wide distribution in the Brazilian savanna. This plant is protected by federal laws and is untouched in deforested areas of the Brazilian savanna. This situation increases the damage to leaves, flowers, and fruits from chewing insects. We studied populations of herbivorous Lepidoptera, Coleoptera, and Hymenoptera and their natural enemies on C. brasiliense trees for three successive years during each season in the Brazilian savanna. Phytophagous insects were most abundant at the beginning of winter and with more species and diversity in the summer. Natural enemies were most abundant in the spring and in the winter and with highest species and diversity at end of the winter. Fruits bored by Carmenta sp. (Lepidoptera: Sesiidae) and Naupactus sp.3 (Coleoptera: Curculionidae) on the leaves were highest in the summer. Fruits scraped by Naupactus sp.l and sp.2 were more numerous in the spring and summer, percentage of defoliation in the autumn. Apoptus sp. (Coleoptera: Elateridae) on the leaves in the spring, and leaf miners (Lepidoptera) in the winter. In the case of natural enemies, Crematogaster sp. (Hymenoptera: Formicidae) were most abundant on the leaves and in the flowers in the winter and spring, and on the fruits in the spring when new leaves and flowers are formed. The number of Zelus armillatus (Hemiptera: Reduviidae), Holopothrips sp. (Thysanoptera: Phlaeothripidae), and the complex of spiders were greater on the leaves in the winter; and Trybonia sp. (Thysanoptera: Phlaeothripidae) was most abundant on the leaves in the autumn