The effect of phosphorus availability on arbuscular mycorrhizal colonization of Typha angustifolia

Although Typha (cattail) species have been reported to be non-mycorrhizal, recent studies have reported arbuscular mycorrhizal (AM) structures in Typha roots, even in very wet habitats. The purpose of this study was to determine the relationship between phosphorus availability and AM colonization of Typha angustifolia. Typha angustifolia was grown in factorial combinations of four phosphorus concentrations (1, 10, 100, and 500 μM P) and two inoculum densities (200 or 500 spores/pot), with an uninoculated control treatment at 100 μM P. After 13 wk, AM colonization was present in the three lowest phosphorus treatments, but was absent from the 500 μM P and control treatments. Colonization did not differ significantly between inoculum density treatments. Shoot dry mass increased significantly with increased phosphorus and was marginally higher in treatments that received 200 spores than 500 spores. Among the 100 μM P treatments, shoot dry mass was significantly higher in the 200 spore treatment than the uninoculated control, but shoot nutrient content did not differ. This study presents clear evidence that AM fungi can colonize T. angustifolia under controlled conditions as a function of phosphorus availability.