Polyphenols in Ceratocystis minor infected Pinus taeda: fungal metabolites, phloem and xylem phenols

Abstract

Since Ceratocystis minor is central to the death of pines infested by southern pine beetles, changes in polyphenols of infected loblolly pine were examined with regard to accumulation of fungal metabolites and changes in concentrations of fungitoxic and fungistatic phloem and xylem constitutents. C. minor grown in liquid culture produced 6,8-dihydroxy-3-hydroxymethyl-1H-2-benzopyran-1-one (I), 6,8-dihydoxy-3-methyl-1H-2-benzopyran-1-one (II), and 3,6,8-trihydroxy-3,4-dihydro-1-(2H)-naphtalenone (III). Isocoumarin II appeared in both phloem and xylem of loblolly pine bolts within 7 to 10 days after inoculation with C. minor. Isocoumarin I was evident in both phloem or xylem. The condensed tannins, catechin, and flavanonols were degraded by C. minor. The stilbenes pinosylvin, pinosylvin monomethyl ether, and a compound tentatively identified as resveratrol initially accumulated, but their concentrations also diminished in later periods of incubation.

Citation

Hemingway, Richard W.; McGraw, Gerald W.; Barras, Stanley J. 1977. Polyphenols in Ceratocystis minor infected Pinus taeda: fungal metabolites, phloem and xylem phenols. Agricultural and Food Chemistry, Vol. 25(4): 717-723