REDUCTION OF PHENOLICS IN MYCORRHIZAS OF LARIX-DECIDUA MILL

Soluble and cell-wall-bound phenolics in mycorrhizas of Larix decidua- laccaria amethystea and in nonmycorrhizal fine roots of larch grown in sterile culture were analyzed by HPLC. The soluble phenolics p-hydrox ybenzoyl glucose, p-hydroxybenzoic acid glucoside, picein, catechin, a nd epicatechin were identified in nonmycorrhizal fine roots. The same phenolics also occurred in mycorrhizas, but only in very small quantit ies compared with those in nonmycorrhizal fine roots. The amount of ce ll-wall-bound ferulic acid was much lower in mycorrhizas than in nonmy corrhizal fine roots. Pure mycelia of Laccaria amethystea (Bull.) Murr . contained none of the identified phenolics. We conclude that L. amet hystea ten induced a large decrease in soluble and cell-wall-bound phe nolics in fine roots of Larix decidua Mill. that may explain their rap id mycorrhization.