Effect of arbuscular mycorrhizae (AM) inoculation on growth performance and bioactive compound production by Andrographis paniculata (Burm.f.) Nees

Abstract

The present study investigates the effects of arbuscular mycorrhizal (AM) fungi, Glomus mosseae and Glomus fasciculatum on the growth and physical parameters of Andrographis paniculata (Burm.f.) Nees (Kalmegh).The AM fungi were inoculated individually in pure culture and in mixed culture to check the combinational effect of AM on the sample plants. The plants treated with AM fungi and respective control plants were harvested at 30, 60 and 90 days of inoculation. Growth parameters (root, shoot, dry weight, wet weight, stem girth and leaf area); physical parameters (alkaloids, flavonoids, saponins, tannins, phenols, proteins, cardiac glycosides, terpenoids and carbohydrate); microbiological parameters (Percentage of mycorrhizal infection) and biological activity (antioxidant, antimicrobial activity) were determined. The results revealed that the AM fungal inoculated plants had significantly higher biomass and growth and new phytochemicals were produced in the treated plant. The average antimicrobial and antioxidant activities were seen to increase in the AMtreated plant samples. The bioactive compounds produced in treated and control plants were characterized by High-performance liquid chromatography, Preparative high-performance liquid chromatography (HPLC), Gas Chromatography-Mass Spectrometry (GC-MS), Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear magnetic resonance (NMR) techniques. The treated plant extract was constituted of Azulene at a higher concentration and was responsible for the bioactivity. In the control plants, Glucopyranoside was produced at higher concentration 4. This study proves that a mixture of AM fungi is more beneficial to the host plant in growth and bioactive compound production than the pure culture.