Pinewood protection against sapstain using citrus essential oils

ABSTRACT Natural color influences the decision to acquire a wood product. Sapstain is a fungal deterioration of pinewood that affects its aesthetic attributes and generally causes its rejection. The aim was to control the sapstain on pinewood with citrus essential oils. Causal agents of sapstain on pinewood were identified by molecular methods to genus level as Alternaria sp., Hypocrea sp., Trichoderma sp., and Geosmithia sp. Citrus essential oils were tested to control the fungal growth. For the treated pinewood probes, the adsorption and retention of citrus essential oils, fungal adhesion, and wood satin as fungal growth indicators were determined. The composition of the essential oils was determined by gas chromatography. Fungi were sensible to essential oils rich in D-limonene, γ-terpinene, α-terpineol, geraniol, eugenol, or β-bisabolene. Absorption and retention data suggest that 12.37±1.62 kg/m3 is the minimal amount to inhibit the fungal adhesion and growth on pinewood. Citrus essential oils control sapstain in pinewood, but poor retention should be improved.