Abstract:
Wood-feeding cockroach (Panesthia angustipennis angustipennis, Blaberidae,
Blattodea) is frequentlyencounteredin decaying wood in acacia (Acacia crassicarpa)
plantation forests on peatlands. The consumption and maceration of wood by this insect
potentially enhance nutrient cycling in this plantation system. Preliminary observations
under field conditions indicated that the roach preferred wood of certain decay levels.
This study was conducted to elucidate the roach’s preference of acacia wood at varying
decay levels. Experiment has been carried out in the laboratory using adult insects,
whichwere caged individually and offered either a wood bait, either one of four decay
levels (TL-I, TL-II, TL-III, and TL-IV). The baits had mass/volume ratiovarying between
0,44 g/cm3 s/d 0,24 g/ cm3 corresponding to the decay level, while the average humidity
of the wood was 56,16%. Observations were conducted every 7 days for 70 consecutive
days. At the end of the experiment, wood bait TL-IV underwent significantly larger mass
reduction(47,12%) than wood bait TL-I, TL and TL-II-III (averagely only about 8,43%).
The mass reduction in wood bait TL-IV was caused by consumption (14,42%) and
maceration (32,70%).
