Retention and concentration of Reticulitermes speratus feeding-deterrent from fungus-decayed Japanese red pine extract

Abstract

Wood-feeding termites and wood-decaying fungi share a niche and likely interact, impacting wood degradation processes. Prior research has primarily examined termite the preferences for decayed wood species, revealing instances of termite feeding deterrence in response to fungal decay products. The compound that caused the deterrence effect was extracted and studies regarding the suspected compound and its toxicity has been previously conducted. In this study, further observation of the extract retention and concentrations were asessed against Reticulitermes speratus. Result indicated that the decayed wood extract retains its deterrent activity for up to four days post-application, with a peak effect observed within the initial hours. Furthermore, the concentration of the extract correlates with both feeding deterrence and termite mortality, suggesting a concentration-dependent relationship. Results show a significant decrease in feeding and increase in mortality with longer exposure durations, indicating sustained deterrent activity for up to four days. Higher extract volumes correlate with reduced feeding and increased mortality, supporting concentration-dependent deterrence. Highest mortality was observed after 24 hours of exposure, suggesting continued toxicity despite diminished deterrence.