Nutritional value and mineral concentrations of sweet basil under organic compared to chemical fertilization

Safe production of leafy vegetables is more important than other horticultural crops due to their significant contribution in health promotion of consumers. In present study, the growth and nutritional quality of sweet basil plants (Ocimum basilicum L.) were evaluated under some organic compared to chemical NPK fertilizing treatments. A non cultivated soil was used in the experiment, and treatments were arranged in completely randomized design with four replications. Manure in 20 and 40% of pot volume, vermicompost in 20 and 40% of pot volume, biophosphate, NPK fertilizer and a no fertilizing control were applied to plants. The results showed that plant growth and biochemical characteristics were differently affected by organic and chemical fertilization treatments. Vermicompost particularly in 20% of pot volume resulted in highest growth and quality parameters, while the lowest values recorded in 40% manure treatment. The leaf content of ascorbic acid, essential oil, protein and minerals (P, K, Mn, Cu) were highest in 20% vermicompost, whereas leaf content of Mg, Fe and Zn was highest in 40% vermicompost treatment. Leaf nitrate content was significantly reduced in all organic treatments than NPK fertilization. Biophosphate also improved the yield and quality traits compared to unfertilized plants, while manure in both quantities reduced most of the traits (leaf vitamin C, oil yield and protein content) except the content of phenols. This indicates that processing as vermicompost can be a better way of manure application for basil production