Study on spatial-temporal variability of volatile components inLagerstroemia indica 'Xiang Xue Yun'

This study aims to determine the spatial-temporal variability of volatile components ofLagerstroemia indica 'Xiang Xue Yun' by headspace solid micro-extraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). The aroma compounds of flowers at four different developmental periods(middle-opening period, full-opening period, late-blooming period, bloom-declining period) and three floral organs(petal, stamen, pistil) in full-opening period were studied. The results showed that: 1) eighty volatile compounds belonging to 11 categories were identified from flowers during the whole flowering process ofL.indica'Xiang Xue Yun', of which, sesquiterpenes, monoterpenes and benzenoids were the main categories with high mass fraction and α-farnesene, pinocarvone and phenylethyl alcohol were the major volatile components emitted with high mass fraction. 2) Volatile compounds emitted fromL.indica 'Xiang Xue Yun' flower during flowering showed six different modes: the continuely-declining pattern; declining first and then rising pattern; the pattern of declining first, rising later and then declining again; continuely-rising pattern; rising first and then declining pattern; the pattern of rising first, later declining and then rising again. 3) In petals, the mass fraction of benzenoids and terpene compounds was high, while in pistil and stamen, the relative content of terpene compounds was high. But the volatile compounds and their mass fraction were distinctly different at different floral organs ofL.indica 'Xiang Xue Yun'. This study lays a good foundation to understand the volatile organic compounds ofLagerstroemia plants and to provide the basis for fragrant breeding of crape myrtle.