Effect of Nitrogen and Potassium Fertilizers on Growth, Yield, Essential Oil and Artemisinin of Artemisia Annua L Plant

This work aimed to study the effect of nitrogen and/or potassium at different rates on the growth, yield, essential oil and artemisinin content of Artemisia annua plant. A field experiment was carried out during two successive seasons in the Farm Station of National Research Centre, Egypt, with loamy clay soil. Data clearly showed that, nitrogen and potassium fertilizers had significant effects on growth characters and yield of Artemisia annua during both seasons. Artemisinin percentage increased with increasing nitrogen treatments, while potassium application decreased artemisinin percentage comparing with unfertilized plants. Application of mineral fertilizers had a significant effect on essential oil % and yield (ml/plant and l/fed) comparing with untreated plants in the two seasons. Artemisia ketone was found to be the first major compound in the essential oil of Artemisia annua and ranged from 32.15 to 64.77% of the total constituents. The highest value of artemisia ketone relative percentage (64.77%) was obtained from plants treated with 75 kg N/fed alone without potassium fertilizers, followed by 1,8 cineole which ranged from its maximum content (31.91%) to its minimum relative percent (12.8 %). For obtaining the highest active compound content in Artemisia annua plants, could be fertilized by 75 kg N + 50 kg K per faddan in case of cultivation for artemisinin production. In case of cultivation A. annua for essential oil production, it is recommended to apply 75 kg N + 25 kg K per faddan under the Egyptian environmental conditions.