Abstract

A field experiment was conducted to study the effect of N levels and planting times on growth, biomass and oil yield attributes, agronomic efficiency (AE) and partial factor productivity (PFP), and economics of N application through marginal analysis. Results indicated that reducing the duration (from planting to harvesting) from December (144 days) to April (74 days) significant result in reduction in percent dry matter production, biomass, oil yield, PFP, AE and net income. Nitrogen application significantly increased dry matter production, leaf/stem ratio, biomass and oil yield in February planted crop. The AE of applied N, were also higher in February planted crop. The AE of applied nitrogen at 50, 100 and 150 kg N ha^-1 were 188, 224 and 200 kg^-1 kg N respectively. At 100 kg N ha^-1 the crop earned a maximum profit Rs. 30.02. The quality of essential oil was not significantly influenced by application of different nitrogen levels.

Key words: Nitrogen, fertilizer, agronomic efficiency, scented geranium.