Dosage de la chitine sur des ectomycorhizes de pin maritime (Pinus pinaster) à Pisolithus tinctorius : évaluation de la masse mycélienne et de la mycorhization

Abstract

To estimate the intensity of mycorrhizal development of maritime pine (Pinus pinaster Soland. in Ait.) associated with Pisolithus tinctorius (Pers.) Coker et Couch., two methods were used: the assay of fungal chitin after acid or alkaline hydrolysis; the measure of absorption of fungus pigments extracted by means of acetone. The products of the hydrolysis of the chitin are assayed by a colorimetric method. The alkaline hydrolysis enables us to directly assay the fungal chitosan; after acid hydrolysis the tissues of pine produce some substances reacting colorimetrically and the absorption due to chitin is estimated from the total absorption of the hydrolysate. There are good correlations between these different types of determination themselves and between the determination and the counting of the mycorrhizae.