Effect of N-sources on nitrogen use efficiency and nutrient content of Ocimum canum plants grown using nutrient film technique (NFT)

Abstract: The aim of the study was to investigate which nitrogen source gives the highest vegetative growth, nutrient uptake and highest nitrogen use efficiency of Ocimum canum plant. Nutrient film technique was used to grow O. canum using different nitrogen sources; Nitrate (calcium and potassium nitrate) (N), urea (U) and Ammonium nitrate (AN) in the same dose. Results showed that in general, growth parameters and nutrient uptake by whole plant and different plant organs were significantly higher in nitrate treatment in comparison with the other sources. The nutrient solution containing ammonium nitrate gave the highest number of leaves, number of branches, height and leaf area per plant, as well as fresh and dry weights. Nitrogen use efficiency of N treatment (57 %) was a little bit higher than of AN (53 %), while U nitrogen utilization was much lower (NUE = 31). In conclusion, when growing O. canum using NFT, it is recommended that N should be supplied as ammonium nitrate.