Populations of A. annua cultivar 'Jeevanraksha' and accession Suraksha were grown in the experimental field plot of the Institute at New Delhi. The seeds were sown in January 2004, seedlings transplanted in late February 2004 and aerial parts (flowers, leaves and stems from the upper 0.5 m of crop canopy) sampled in late October 2004.

Ninety-seven compounds comprising 91.3% of the total oil of 'Jeevanraksha' were identified. Forty-three monoterpenes (56.6%), 32 sesquiterpenes (31.1%), and 2 diterpenes (0.2%) comprised bulk of the oil (87.9%). The oil was devoid of artemisia ketone and contained camphor (13.5%), 1,8-cineole (9.4%), trans-sabinol (7.1%), p-mentha-1(7), 5-dien-2-ol (6.3%), myrcene (4.7%), germacrene D (4.4%), (E)-beta-farnesene (3.9%), beta-caryophyllene (3.7%), dihydroartemisinic lactone (3.0%) and p-cymene (2.0%) as the major constituents. Eighty-six compounds representing 93.3% of the composition were identified in the Suraksha oil. This oil contained artemisia ketone (47%), 1,8-cineole (8.4%), camphor (5.9%) and alpha-pinene (5.2%) as the major components.

The aerial parts of T. flavum were collected in different periods from December to July 2006, from plants growing along the Ionic coast of Sicily (Italy). LF 1-LF 2-LF 3: represent the composition of leaf oils of plant samples collected in December (vegetative stage), February (pre-flowering stage) and April (budding stage) respectively; FL: flower oil; FR: fruit oil.

Some components, in all investigated plant parts, remained more or less constant during all the different phases of the plant cycle life. Worthy of note, considering the leaf oils, was that beta-pinene, limonene and germacrene D increased in the pre-flowering stage, while a series of esters and alpha-copaene, beta-caryophyllene, viridiflorol, Tmuurolol and phytol increased in the budding stage (LF3); the vegetative stage oil is generally characterized by a rich chemical composition and some constituents such as isoamyl hexanoate, alpha-humulene, bicyclogermacrene, beta-bisabolene and alpha-bisabolol reached their highest levels in this oil. In the flower oil, linalool and 1-octen-3-yl acetate were the main components compared to the amounts found in the other oils. Fruit oil composition was relatively oil poor, with beta-bisabolene, caryophyllene oxide, cadin-4-en-1-ol and phytone as the major constituents.