Susceptibilidade de cinco essências florestais (quatro nativas e uma exótica) à ação do cupim subterrâneo asiático, Coptotermes gestroi (Wasmann, 1896) (Isoptera: Rhinotermitidae)

Abstract

Termites are well-known for their capacity to damage and destroy wood and wood products of all kinds. However, physical and/or chemical properties of the wood of different forest species result in variability in wood characteristics, which will ultimately cause variability in wood resistance to termites. In this context, the objective of this present work was evaluated the wood susceptibility of five forest species: pinus (Pinus spp., Pinaceae) as exotic species, castanheira (Bertholletia excelsa H.B.K., Lecythidaceae), angelim (Andira inermis (Sw.), Leguminosae-Papilionoideae), maçaranduba (Manilkara huberi (Ducke), Sapotaceae] and ipê (Tapebuia avellanedae Lor. Ex Griseb, Bignoniaceae) as native Brazilian species, under field condition to action of the subterranean termites. Wooden stakes of theses forest species were made with dimension of 16 cm long by 2 cm of width and 2 cm of thickness, and were installed on 11 sites, which were localized in the campus of Universidade Federal Rural do Rio de Janeiro (UFRRJ) and the residential area of Ecologia district in the municipality of Seropedica, Rio de Janeiro, Brazil, from September 2nd, 2006 to June 7th, 2007. The experiment was set up in randomized complete-block design with 11x5x3 factorial arrangement (11 sites of stake installation, five forest species and three field exposition times: 90, 180 and 270 days after installation), with four replicates, totalizing 660 stakes. The results obtained showed that the wooden stakes of the five forest species evaluated were infested by Coptotermes gestroi (Wasmann) (Isoptera: Rhinotermitidae). It was observed that the feeding behavior of C. gestroi was influenced by wood density, which was direct and inversely related with the wood consumption by this termite. The wood of pinus and castanheira show low and intermediary values of density, being considerate soft and moderated hard wood, then less dense and were more susceptible to attack of C. gestroi in relation to the wood of angelim, ipê and maçaranduba, which did not have significant damages caused by C. gestroi up to 270 days of field exposition.