Abstract: Volatile compounds in Camellia azalea flowers at different stages during flower development, in their different parts and at different hours of a day were analyzed by solid phase micro-extraction and gas chromatography-mass spectrometry (GC-MS). Totally 8, 20, 21 and 17 volatile compounds were identified in early-stage, full bloom and withering flowers, respectively. Volatile compounds were released mainly during the early flowering and full bloom stages. During flower development, the content of alcohols revealed a gradual increase. Alkenes, esters and alkanes revealed an initial increase and a final decrease, while aldehydes and ketones revealed a decrease trend during the whole process. Totally 20 compounds were identified in sepals, 22 in petals, 21 in stamens and 13 in pistils. The major parts releasing volatile components were petals and stamens. Alkanes were the most dominant volatile compounds in sepals, stamens and petals, accounting for 49.86%, 51.59% and 44.66% of the total volatiles, respectively, while the most dominant volatile compounds in pistils were aldehydes and ketones with a relative content of 83.87%. An obvious intraday variation was observed in the relative contents of volatile compounds in Camellia azalea flowers. The peak hours for releasing alkenes, alcohols, esters and alkanes were 8:00 to 12:00, while higher release levels of aldehydes and ketones were found from 14:00 to 18:00.

Key words: Camellia azalea, volatile component, gas chromatography-mass spectrometry (GC-MS)