Roots of V. aphylla only develop hairs where roots of neighbouring plants or organic litter is attached. Fungal penetrations almost exclusively occur at these root-to-root attachments. The ecological significance of these immediate hyphal bridges for achlorophyllous plants is discussed.
The morphological and anatomical features of the root of Voyria aphylla, as well as its Paris-type arbuscular mycorrhiza (AM) appear to be transitional between those of V. truncata and V. tenella. A hypothetical evolutionary progression of AM and its significance for the development of myco-heterotrophy is proposed.
Key words: Voyria, Gentianaceae, root structures, arbuscular mycorrhiza, myco-heterotrophy.