Influence of transplanting time on essential oil yield and composition in Artemisia annua plants grown under the climatic conditions of sub‐tropical north India

The yield and composition of the essential oil obtained by hydrodistillation of inflorescences from different populations of Artemisia annua L. (Asteraceae), transplanted during different months, was analysed using a combination of GC and GC–MS. Oil yield was found to range from 0.5 to as high as 1.6% (w/v), in which 24 constituents were identified, representing 84.4–92.2% of the total oil. Camphor was identified as the most abundant component in all the samples examined, followed by 1,8‐cineole, except in June‐transplanted plants, where b‐caryophyllene was found to be the second most abundant compound. Camphor and 1,8‐cineole alone constituted 44.7–65% of the total oil. The percentage occurrence of rest of the compounds was found to vary in different populations.