Impact of Shade Intensities on Rhizome Yield and Quality of Costus speciosus: A Viable Option as an Intercrop

The maximum number of stems/plants, stem weight, root length, rhizome spread, fresh rhizome weight and dry rhizome weight were observed under 75% Shade Intensity (SI) followed by 50% natural SI. The light response study revealed that net Photosynthetic Rate (PN) was maximum at 1000 μ mol (photons) m^-2 s^-1 and further increase in light intensity decreased the PN. The NPQ increased steadily and this kind of PAR requirement (?750 μ mol) makes the plant suitable for partially shade area with very low light transmission. Diosgenin content in rhizome was low in all shaded plants as compare to 0% SI (open field conditions) in which it was maximum (826 mg g-1). Over all rhizome and diosgenin yield content were maximum under 75% natural SI as an intercrop.