Endomycorrhizas and legume growth in some soils of the Mackenzie Basin, Canterbury, New Zealand

Abstract

Endomycorrhizal plants of Trifolium repens and T. pratense grew better than non-mycorrhizal plants in a range of fertilised and unamended soils kept in a glasshouse. The relative benefit of mycorrhiza formation increased as phosphorus availability and dry matter yields decreased. The same mycorrhizal fungus was parasitic on T. hybridum and Medicago sativa, reducing growth by 3–16%. These results indicate that endophyte-host relationships in the symbiosis change from mutualism to parasitism as phosphorus availability increases.