Optimization of plant population and nitrogen requirement for commercial cultivation of Kalmegh (Andrographis paniculata Nees) under Indo-Gangetic plains of north India

摘要

To optimize the plant population density and nitrogen requirement of Andrographics paniculata under indo-Gangetic plains, a field experiment was conducted in a sandy loam soil during rainy season (July-October) at the research farm of the Central Institute of Medicinal and Aromatic Plants, Lucknow. Sixteen treatments comprising of four plant population densities (66,666, 111,111, 222,222 and 444,444 plants ha~(-1) by planting at 50 x 30cm, 30 x 30cm, 30 X 15cm and 15 x 15 cm spacing, respectively) and four nitrogen levels (0, 40, 80 and 120 kg ha~(-1)) were tested in a factorial randomized block design with three replications. Yield contributing traits such as plant height, number of branches per plant, leaf area index (LAI), dry biomass and contentof diterpenoid lactones (Andrographolide + neo-andrographolide) registered a significant increased at a plant population of222,222plants ha~(-1) and application of 80 kg ha~1nitrogen. The optimum dose of N was worked out to be 90.7 kg ha~1 that gave a maximum dry biomass yield of 3833.7 kg ha~1.