Role of Plant Growth Regulators for Improving Andrographolide in Andrographis Paniculata

The present study was aimed at improving the content of therapeutically active principle, andrographolide and whole plant biomass of Andrographis paniculata (Burm. F.) Wall.Ex Nees, by foliar application of plant growth regulators. The pot cultured plants were treated with Gibberellic acid (GA3), Indole acetic acid (IAA), Naphthalene acetic acid (NAA) and Benzyl amino purine (BAP), in the concentration of 25, 50, and 100mg/l each. The plants sprayed with distilled water were maintained as control. The foliar application of these growth regulators was initiated at 30 DAT and continued upto flowering stage at an interval of 10 days. The HPLC analysis revealed that, application of IAA-50mg/l was very effective to enhance the andrographolide content (45%), which was followed by NAA-50mg/l (37%) over control. The whole plant biomass (Panchang) of Andrographis is used in medicine and hence fresh and dry biomass was also determined. The results indicated that NAA (Fresh Weight: 221%, Dry Weight: 155%) and IAA (Fresh Weight: 215%, Dry Weight: 120%) emerged out as the best treatments for improving fresh and dry biomass over control. The treatments of IAA and NAA (50mg/l) were found to be most effective for improving whole plant biomass as well as andrographolide content which can be recommended for the growers.