Abstract

Two independent field experiments were conducted at Punjab Agricultural University, Ludhiana, Punjab, India in 2006 and 2007 in a loamy sand soil normal in soil reaction and electrical conductivity, low in organic carbon and available nitrogen, medium in phosphorus and potassium status in a complete randomized design with four replications to study the effect of different levels of farmyard manure (FYM) and nitrogen on the yield and nitrogen uptake of Stevia rebaudiana Bertoni. Four levels of farmyard manure (0, 15, 30 and 45 t/ha) and four levels of nitrogen (0, 20, 40 and 60 kg/ha) were tested. Biomass yield (kg leaves/ha) and several other yield parameters (dry leaf yield, number of leaves per plant, leaf area index and dry matter accumulation per plant) were highest in plants grown at the highest level of farmyard manure (45 t FYM ha^-1). Maximum nitrogen uptake was also recorded under 45 t FYM ha^-1 in both experiments. Plants grown at 40 and 60 kg N ha^-1produced significantly higher number of branches, number of leaves per plant, and showed higher leaf area index and nitrogen uptake compared to lower nitrogen levels. Dry leaf yield and dry matter accumulation per plant was highest at 60 kg N ha^-1.

Key words: Stevia, farmyard manure, nitrogen, yield, nitrogen uptake.