Effect of chemical and biological nitrogen on quality and quantity of anise (Pimpinella anisum L.)

In order to evaluate the effect of chemical and biological nitrogen on growth and secondary metabolites production of Pimpinella anisum L., a factorial experiment was conducted based on randomized complete block design with three replications. Chemical nitrogen in three levels of 0, 60 and 120 kg/ha and biological nitrogen (nitroxin) in three levels of 0, 3 and 6 L/ha were applied as treatments. Results showed that the effect of chemical nitrogen and nitroxin on fertile ombellete/umble, seed yield, essential oil content and essential oil yield, biologic yield, harvest index seed and harvest index essential oil was significant. Means comparisons showed that the maximum (13.1) and minimum (12.2) number of ombellete/umble were respectively recorded for the treatment with 3 l/ha nitroxin and control treatment (without chemical and biological nitrogen). The highest seed yield (872.8 kg/ha) was obtained from 3 L/ha nitroxin and 60 kg/ha chemical nitrogen while the lowest seed yield (478.3 kg/ha) was obtained from control treatment. According to the results, maximum essential oil yield (115.14 kg/ha) was recorded for the treatment of 3 L/ha nitroxin and 60 kg/ha chemical nitrogen, and the minimum oil yield (55.35 kg/ha) was obtained from control treatment.