Effect of vesicular arbuscular mycorrhizae on growth and saponin accumulation in Chlorophytum borivilianum

Safed musli (Chlorophytum borivilianum) contains pharmacologically important steroidal saponins that have attracted pharmacological societies and researchers worldwide. To estimate the beneficial effects of different vesicular arbuscular mycorrhiza (VAM) and C. borivilianum symbiotic association we studied phosphorus uptake, root carbon, spore build up, root dry mass, and saponin accumulation in different harvesting periods. In the VAM colonized roots studied, a significantly higher spore build-up was found in Glomus intraradices and Glomus mosseae than in the Glomus fasciculatum or non-colonized treatment at the critical growth stage of the species (90 days). However, all the mycorrhizal treatments showed significant increase in phosphorus uptake and root carbon percentage. The results reveal that mycorrhizal fungi substantially enhance the saponin content of C. borivilianum, depending upon the type of VAM fungi supplied. G. mosseae contributed 5 fold (0.56 g to 2.8 g/plant) enhancements in saponin accumulation followed by G. intraradices (0.56 g to 2.7 g/plant) in comparison to non-mycorrhizal plants. After 270 days, saponin content and root growth in all the mycorrhizal inoculated plants was found to be greater than in non-mycorrhizal material. The present study is a first report of an increase in secondary metabolite accumulation and root growth enhancement in C. borivilianum as an effect of mycorrhizal inoculation.