Effects of Soil Application of Amino Acids, Ammonium, and Nitrate on Nutrient Accumulation and Growth Characteristics of Sweet Basil

The use of organic or reduced form of nitrogen (N) can have various beneficial effects in terms of plant nutrient uptake, metabolism, and environmental issues. In this study, the influence of soil application of reduced N-forms (ammonium, glycine, and glutamine) compared to nitrate and a no fertilizer treatment was evaluated on growth characteristics of sweet basil (Occimum basilicum L.) under a moderate lime soil conditions. The basil growth traits including root and shoot biomass were increased under application of reduced N-forms mainly glycine and glutamine compared to no fertilizer treatment. Application of reduced forms of nitrogen (ammonium, glycine, and glutamine) increased the leaf concentrations of potassium (K), magnesium (Mg), calcium (Ca), iron (Fe) and zinc (Zn), whereas the leaf N concentration was increased by ammonium and nitrate fertilization compared to unfertilized control plants. The results indicate that soil application of reduced N-forms particularly glycine and glutamine is superior to nitrate application.