Abstract
The major components and fungicidal activities of commercial pyroligneous acids, bamboo vinegar, and home-made crude pyroligneous acids collected from a charcoal production facility were determined. Large variations in concentrations of the major components were found among the commercial products. In case of home-made crude pyroligneous acids, the quality changed depending upon temperatures at which the acids were collected, being especially remarkable at high temperatures. Toxic substances such as methanol, formaldehyde, and phenols were also detected along with acetic acid. Variations in concentrations of toxic components made it difficult to do risk assessment of pyroligneous acids as a whole. Although some anti-microbial activity was observed against Downy mildew on a culturing medium, little effect was demonstrated on actual plants in controlling against three plant pathogens; downy mildew, botrytis rot, and mildew.
