Impact of mycorrhizal colonisation on root architecture, root longevity and the formation of growth regulators

Until relatively recently, it was assumed that arbuscular mycorrhizal fungi (AMF) did not influence the morphology of the root system. (1983) concluded “little change in root morphology occurs following infection. Root apices continue to grow in an apparently normal manner. “...It is usually not possible to tell if a root system is mycorrhizal...” A number of recent studies, however, reviewed by (1993a) have demonstrated effects of AMF on a range of morphological parameters. While effects of AMF are less extreme than those of ecto-mycorrhizas they have the potential to be of equal importance. The existence of effects raises questions as to how these effects are caused.