Natural resistance of Tectona grandis wood in laboratory assay/Resistencia natural da madeira de Tectona grandis em ensaio de laboratorio

• Published in: Ciência rural Vol. 43; no. 8; p. 1393
• Main Authors: Motta, Javan Pereira, Oliveira, Jose Tarcisio da Silva, Paes, Juarez Benigno, Alves, Rejane Costa, Dambroz, Graziela Baptista Vidaurre
• Format: Journal Article
• Language: Spanish
• Published: Universidade Federal de Santa Maria 01-08-2013
• Subjects: Molds (Fungi); Termites
• ISSN: 0103-8478

This research aimed to evaluate the natural resistance of teak wood (Tectona grandis) to xylophagous fungi and termites in laboratory conditions. It was used trees with fifteen years old, from a plantation of the Forest Enterprise Celulose Nipo Brasileira--CENIBRA S.A., located in Belo Oriente, Minas Gerais State, Brazil To determine the natural resistance of teak wood in laboratory were employed the Postia placenta, Neolentinus lepideus, Polyporus fumosus and Fomes connatus fungi and to termites resistance was employed the feeding preference assay with subterranean termites Nasutitermes sp. Samples were taken from four positions in the stem (heartwood near the pith, heartwood intermediate, outer heartwood and sapwood) at 1,30m to soil level and submitted to the action of fungi for thirteen weeks and termites for 45 days. It was found that the heartwood of teakwood from the Vale do Rio Doce, Minas Gerais State, Brazil was highly resistant. The internal heartwood was less resistant than the other portions of the heartwood to action of wood decay agents, while the sap-wood was classified as moderately resistant (Polyporus fumosus) or resistant (Postia placenta and Neolentinus lepideus). Key words: teak wood, termites, fungi, natural durability. O objetivo da pesquisa foi avaliar a resistencia natural da madeira de teca (Tectona grandis) a fungos e termitas xilofagos em condicoes de laboratorio. As arvores empregadas possuiam 15 anos de idade, provenientes de um plantio da Empresa Celulose Nipo Brasileira--CENIBRA S.A., localizada no municipio de Belo Oriente, Estado de Minas Gerais. Para a determinacao da resistencia natural da madeira a agentes xilofagos, foram realizados ensaios de apodrecimento acelerado em laboratorio com os fungos Postia placenta, Neolentinus lepideus, Polyporus fumosus, e de preferencia alimentar com cupins subterraneos Nasutitermes sp. Corpos de prova foram retirados em quatro posicoes no sentido medula casca: cerne interno (proximo da medula), cerne intermediario, cerne externo (proximo ao alburno) e no alburno, na altura de 1,30m do nivel do solo e submetidos a acao dos fungos por 13 semanas e cupins por 45 dias. Constatouse que o cerne da madeira de teca proveniente do Vale do Rio Doce, Minas Gerais, foi altamente resistente, tendo o cerne interno sido menos resistente que as demais porcoes do cerne a acao dos agentes xilofagos, enquanto a madeira de alburno foi classificada como de resistencia moderada (Polyporus fumosus) ou resistente (Postiaplacenta e Neolentinus lepideus). Palavras-chave: madeira de teca, termitas, fungos, durabilidade natural.