Utilisation of press mud for organic cultivation of Andrographis paniculata Wall. ex Nees in reclaimed sodic soil

Andrographis paniculata is a medicinal plant used to treat many different ailments. The biomass of A. paniculata can be used safely either as fresh plant material, after decoction, or in pharmaceutical formulations. In the present study, different application rates of press mud were evaluated for organic cultivation of A. paniculata in the Indo-Gangetic Plains of Uttar Pradesh, India. The vegetative plant growth parameters were positively affected by increased application rates of press mud up to 7.5 and 10 t ha^-1. Macro- and micro-nutrient (N, P, Ca, Fe, Zn, Cu, Mn, Mo and Ni) concentrations of the plant tissue increased with the application of press mud. Yields of active compounds in the A. paniculate, i.e. andrographolide, neo-andrographolide and wogonin, increased in line with the increased total plant biomass in response to increased press mud application rates. Soil microbial populations, total heterogeneous bacteria, fungi, actinomycetes and Azotobacter also increased with increased rates of press mud, as did soil enzyme activities, i.e. dehydrogenase, β-glucosidase, urease, protease and acid phosphatase. Soil pH and bulk density decreased with increased rates of press mud, which was seen as indications of improved soil properties. Furthermore, available macro- and micro-nutrient concentrations in the soil increased with increased rates of press mud. The present study demonstrated that in organic cultivation of A. paniculata, optimised application rates of press mud can be used not only to supplement soil nutrients but also to enhance yields of plant biomass and active constituents of A. paniculata.