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Made available in DSpace on 2021-06-25T11:05:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-01 Entomopathogenic nematodes (EPNs) can control pests due to mutualistic association with bacteria that reproduce and kill the host from septicemia, making the environment favourable for nematode development and reproduction. The objective of this study was to identify an EPN isolate collected in eucalyptus cultivation and to determine its pathogenicity with regard to Gonipterus platensis Marelli (Coleoptera: Curculionidae). Four steel-mesh traps with two seventh-instar Galleria mellonella larvae were buried 5 cm deep in the soil in a commercial Eucalyptus plantation. After 7 days, the traps were packed in plastic bags and transported to laboratory to isolate the EPNs using White traps. The obtained nematodes were multiplied in G. mellonella larvae and identified by sequencing their D2/D3 expansion of the 28S rDNA region by polymerase chain reaction (PCR) and specific primers for ITS regions. Steinernema diaprepesi was identified and inoculated into G. platensis pupae at doses of 500, 1000 and 5000 infective juveniles (IJs) to determine its pathogenicity to this pest. At 8 days after inoculation, the mortality rate of the G. platensis pupae was 80% with the lowest concentration and 100% with the others. The emergence of nematodes and the rapid degradation of G. platensis pupae were observed in those inoculated with IJs. The pathogenicity to the G. platensis pupae indicates potential for using this nematode in the integrated management of this insect. Universidade Estadual Paulista (UNESP) Departamento de Protecąõ Vegetal Departamento de Protecąõ Vegetal Departamento de Entomologia/BIOAGRO Universidade Federal de Viçosa Departamento de Engenharia Florestal Universidade Federal de Viçosa Universidade Estadual Paulista (UNESP) Departamento de Protecąõ Vegetal Departamento de Protecąõ Vegetal

The knowledge of the technological properties of the wood is important for the management and rational use of forest species. The study of the physical properties of Calycophyllum spruceanum wood aims to provide subsidies for timber production in estuarine floodplain forests. Samples were collected at base and top of the stem from 15 trees with different diameters to determine the physical properties (basic density, anisotropic factor and axial, radial, tangential and volumetric shrinkage), according to NBR 7190/97. C. spruceanum wood showed overall average of 0.65 g.cm-3 for density, 5.1% for radial shrinkage, 7.3% for tangential shrinkage, 14.1% for volumetric shrinkage and 1.6 for anisotropic factor. By analysis of covariance there was a significant effect of position on the stem only for anisotropic factor and tangential shrinkage, where the highest values for these properties were obtained at the base of the stem of the trees. The inexistence of significant effect of diameter at breast height (DBH) trees on the physical properties studied associated with values of basic density and adequate, from the aspect of dimensional stability for the anisotropic factor show that the timber of the species presents possibilities to be used as solid wood, even from trees under the minimum logging diameters (50 cm), established by Brazilian law.

O mundo busca fontes alternativas para a produção de adesivos utilizando matéria-prima renovável. Nesse contexto, a utilização de taninos da casca de barbatimão, Stryphnodendron adstringens (Mart.) Coville, tem apresentado potencial. O objetivo deste trabalho foi avaliar a viabilidade técnica de utilização de Adesivos tânicos provenientes das cascas de barbatimão para a produção de painéis aglomerados. Adesivos à base de taninos extraídos das cascas de barbatimão foram usados na proporção de 0, 25, 50, 75 e 100% com o adesivo comercial ureia-formaldeído. Os adesivos puros e o das misturas tiveram suas propriedades determinadas. Painéis aglomerados com os adesivos ureia-formaldeído, tanino-formaldeído e as misturas destes foram produzidos e suas propriedades físico-mecânicas, testadas. O adesivo tânico de barbatimão mostrou-se viável tecnicamente na proporção de até 50% para painéis reconstituídos do tipo aglomerado, com a ressalva de recomendação para uso apenas em ambientes internos, sem contato com a umidade. The world seeking alternative sources for adhesives production by using renewable raw material. In this context, the use of Stryphnodendron adstringens (Mart.) Coville tannins bark have been showing potential. The aim of this study was to evaluate the technical feasibility of using tannic adhesive from the barks of barbatimão, for particleboard production. Tannin-based adhesives extracted from the bark of barbatimão were used in ratio of 0, 25, 50, 75 and 100% with commercial urea formaldehyde adhesive. Pure and mixtures adhesives had their properties determined. Particleboards with urea-formaldehyde, tannin-formaldehyde and its mixtures were produced and had their physic-mechanical properties tested. The adhesive tannic of barbatimão proved be technically feasible in the proportion until 50% for particleboard panels type, however, it is recommended to indoors use only, without moisture contact.

Made available in DSpace on 2022-04-28T21:25:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-10-13 Ants of the genus Atta are the main pests of Brazilian agriculture, including annual crops, pasture and reforestation. Atta laevigata (F. Smith) (Hymenoptera: Formicidae) presents a wide distribution from the Northern Amazon Basin Region to Southern Brazil. However, this is the first report of its occurrence in the Espirito Santo State, Brazil where it was found in the Municipality of Castelo at 20° 36'13 South Latitude, 41° 11'05 West Longitude and an average altitude of 100 meters. The low number of nests of A. laevigata compared to those of Atta sexdens rubropilosa Forel may indicate that the first species has been recently introduced or is endangered in Espírito Santo State due to competition with other organisms or by the impact of anthropogenic factors. Departamento de Engenharia Florestal Universidade Federal de Viçosa, 36570-000 Viçosa, Minas Gerais Departamento de Biologia Animal/BIOAGRO Universidade Federal de Viçosa, 36570-000 Viçosa, Minas Gerais Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro Departamento de Entomologia Universidade Federal de Lavras, Caixa Postal 3037, 37200-000, Lavras, Minas Gerais Departament of Plant Protection UNESP University of the State of São Paulo, 14884-900 Jaboticabal, São Paulo State Departamento de Biologia Geral Universidade Federal de Viçosa, 36570-000 Viçosa, Minas Gerais Departament of Plant Protection UNESP University of the State of São Paulo, 14884-900 Jaboticabal, São Paulo State