The Fine Structure of the Mycorrhizas of Pinus Radiata D. Don

Abstract

The fine structure of one of two common types of mycorrhiza formed by Pinus radiata D. Don is described. The results showed inter alia that the ability of a fungus to form mycorrhiza depended on its tolerance to polyphenolic compounds in the so-called tannin layer of the cortex. Hartig net formation is a process in which the invading fungus lysed the middle lamellae and then separated the cells of the host by mechanical action. Evidence of the transfer of carbohydrate from the cortical cells of the host into the fungus in the Hartig net was obtained. Typical dolipore septae were observed both in the mantle and Hartig net hyphae. A new and hitherto undescribed structure was observed in the fungal partner.