Reducing Activity at the Root Surface in Eucalyptus pilularis–Pisolithus tinctorius Ectomycorrhizas

Abstract

Mycorrhizal and non-mycorrhizal areas of root systems of Eucalyptus pilularis Sm. seedlings, grown in growth pouches and inoculated with Pisolithus tinctorius (Pers.) Coker & Couch, were compared with regard to their surface reducing activity. Mycorrhizal roots were shown to reduce silver bromide, ferric EDTA and a higher oxide of manganese while non-mycorrhizal roots of the same plants did not. A number of ecto- and endomycorrhizal fungi were screened for reducing ability. All fungal isolates tested, with the exception of Hebeloma crustuliniforme and a suspected ectomycorrhizal symbiont from Pisonia grandis roots, were capable of reducing a manganic oxide.