Seedling Growth and Secondary Metabolism of Taxus chinensis as Affected by Arbuscular Mycorrhizal Fungi

Objective The symbiotic effects of the arbuscular mycorrhizal fungi (AMF) on the growth and secondary metabolism of Taxus chinensis seedlings were investigated.

Method Rhizosphere soil of T. chinensis seedlings were artificially inoculated with the AMF, Rhizophagus intraradices and/or Funneliformis mosseae, as the plants were growing in a pot experiment. Seedling growth measured by the plant height, primary root length, and underground girth as well as plant secondary metabolite paclitaxel and physicochemical qualities of the soil were monitored.

Result  (1) The AMF inoculation significantly raised the height, underground stem diameter, root length, and number of primary branches of the seedlings. Simultaneously applying R. intraradices and F. mosseae significantly increased the height and root length of the seedlings. Individually, R. intraradices rendered the most significant effect on the growth of underground plant parts, while F. mosseae on the number of top-graded branches. (2) AMF proliferation was affected by the chemical composition of the soil with the infecting rate significantly correlated negatively with the quick-acting phosphorus (p＜0.05) and positively with the alkali soluble nitrogen and quick-acting potassium (p＜0.05). And (3) the presence of AMF, especially R. intraradices, in the rhizosphere soil significantly heightened the paclitaxel secretion.

Conclusion The symbiosis between T. chinensisand R. intraradices, more than that between T. chinensis and F. mosseae, significantly enhanced the growth and secondary metabolism of the seedlings.