Flavan accumulation in stems of<i>Platanus</i>×<i>acerifolia</i>seedlings inoculated with<i>Ceratocystis fimbriata</i>f.sp.<i>platani</i>, the canker stain disease agent

Abstract

Inoculation of Platanus × acerifolia stems with Ceratocystis fimbriata f.sp. platani, the canker stain disease agent, induced the accumulation of preexisting phenolic compounds such as flavan-3-ols and proanthocyanidins in the infected internode of the stem. These flavan compounds and their polymerized products were most quickly accumulated near the inoculation site, particularly in the medulla, vascular tissues, tyloses, and gels. Thus, these plane tree reactions were considered as defensive responses. Their involvement in the restriction of Ceratocystis fimbriata f.sp. platani development around the inoculation site, associated with other located responses previously described, was discussed. Keywords: Ceratocystis fimbriata, flavan-3-ols, Platanus × acerifolia, proanthocyanidins.