Resistência das madeiras de pinus, cedro australiano e seus produtos derivados ao ataque de Cryptotermes brevis

Abstract

The aim of this work was to compare the resistance of Australian red cedar (Toona ciliata) and pine (Pinus sp.) woods and particleboards made from these species to dry-wood termite Cryptotermes brevis attack, as much as to quantify the mortality of the insects. 30 termite pseudo-workers were put in each 9,5 cm-diameter Petri dishes containing the samples (1,5 x 1,5 x 0,5 cm) and cotton sheets positioned on the perforated covers, daily moisturized with 5 ml of water. The dishes were maintained in BOD (Biological Oxygen Demand) at 24±5 °C and 24 h of escotophase. A control sample without any feed source was included in the bioassay. The deterioration index (ID) and mortality of the insects were evaluated after 60 days. Termites from the control sample presented higher termite mortality than the other treatments, which did not differ among each other. Toona ciliata wood was more resistant than Pinus sp. wood to Cryptotermes brevis attack. The average deterioration indexes were 1.74% and 6.62% respectively for those woods. The average deterioration index of the panels made with 100% Toona ciliata (ID=1.58%) was similar to the deterioration index of particleboards made with this specie mixed with Pinus sp. (ID=1.87%).