Natural resistance of Bambusa vulgaris to termite and powder-post beetle attack in laboratory and graveyard tests
N A Sadiku, S O Bada
Deterioration is the major setback to the utilisation of bamboo products. To enhance bamboo utilization, an understanding of the level of resistance to degradation is important. In this study, level at which Bambusa vulgaris will naturally resistant attack by subterranean termites and powder-post beetles were evaluated. B. vulgaris aged 2, 3 and 4 years were subjected to attack by subterranean termites and powder-post beetles for six month in a short span field tests. After the exposure period, the weight loss due to attack were determined in order to evaluate the level of natural resistance to the selected degrading insects. There was significant variation in the termite resistance among the three age classes while no variation occurred along the culm length. In contrast to termite resistivity, resistance to powder-post beetles infestation varied significantly along the culm length from base to the top while the resistance among the three age classes were similar. The bamboo was grouped into resistant classes based on the age and the portion of the culm from which samples were extracted. Bamboo aged 4 exhibited highest resistance to termites and were therefore placed in “Resistant” class while bamboo from age 3, basal and middle portion were placed in “Moderately resistant” class. The resistance of B. vulgaris from all the age classes and culm portion against powder-post attack was poor and were placed in class IV. B. vulgaris resistivity to termite and powder-post attack had significant negative correlation with culm age and portion respectively. Generally, the findings of this work showed B. vulgaris natural resistant to termite depend on culm age while that of powder-post is indifferent to age or the culm portion.
Keywords: bamboo, culm age, culm portion, chemical content, biodegradation, resistivity
Conference: 18-04-29/05-03 Johannesburg, South Africa