###### Abstract
The floral scent (as a chemical composition) from two distinct genotypes of Iranian _R. damascena_ flowers was analyzed at six stages of flower development by using a simple HS extraction. The main floral components were 2-phenyl ethyl alcohol, \(\beta\)-citronellol, \(\alpha\)-pinene, benzyl alcohol, and geranyl acetate, with variations depending on the stage of development [14]. Three varieties of Damask rose ('Four Seasons', 'Celsiana', and 'Rose de Rescht') were studied in China in a dry and frozen climate [15]. The volatiles emitted from flowers were collected by an improved dynamic HS air-circulation method [16] and were detected and identified via thermal-desorption cold trap-GC/MS technique. The results revealed that 63, 68, and 55 species of individual compounds were detected, respectively. _R. damascena_ Mill. volatiles were studied by HS-SPME at various conditions (fresh, stored at 4 \({}^{\circ}\)C, and dried rose petals), identifying 20 volatile compounds [17]. Polydimethylsiloxane (PDMS) coated fused-silica fibers were used as the most suitable ones for adsorbing volatile compounds from the rose petals [18]. The detected compounds varied according to the various storage and drying conditions. It was determined that phenylethyl alcohol, citronellol, geranyl acetate, and nonadecane were predominant compounds in all treatments. Similar analysis was performed by [PERSON] and co-authors [19] by using carboxen/polydimethylsiloxane fibers, showing that considerable variability in floral scent molecules such as phenylethyl alcohol (23.26-74.54%), citronellol (5.57-31.59%), and geranyl (3.09-26.93%) was recorded among the seed-derived plants. Rose scent of Egyptian _R. damascena_ Mill. unexpanded and expanded rose flowers at different levels of blooming were determined using HS-SPME [20]. SPME fibers coated with divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS, 50/30 \(\upmu\)m), PDMS(polydimethylsiloxane) were used. A total of 75 volatiles were detected, with alcohols, esters, and oxides as valuable volatile classes at ca. 64%, 10%, and 2%, respectively, in expanded flowers compared to 46%, 2%, and 0.4% in unexpanded ones. [PERSON] and co-workers [21] used dynamic and static HS to investigate the aroma profile of modern tea-hybrid roses 'Lady Hillingdon', 'Diorama', and 'Grand Mogul' along with ancient Chinese roses in order to assess the genealogy of the latter. A substantial number of Seventy-two volatile components from the flowers ('Lady Hillingdon'--72, 'Diorama'--76, and 'Grand Mogul'--67) were identified. A HS-SPME method in combination with gas chromatography (GC) coupled with flame ionization detection (FID) and MS was developed and optimized to investigate volatile organic compounds from different tissues (flowers, leaves, stems, rhizosphere, and whole plants) of Floribunda and Hybrid Tea roses (intact and cut) [22]. Three-phase fiber 50/30 \(\upmu\) divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) was used. Three taxa of _Rosa odorata_ and three taxa of _R. chinensis_ germplasm resources were examined for their VOC profiles at different flowering stages by sensory analysis and SPME-GC/MS analysis [23]. DVB/CAR/PDMS was used as an extraction fiber. More than one hundred VOCs were detected, including 33 major compounds. The performed principal component analysis showed characteristic substances such as some benzodiazepines and sesquiterpenoids, which could be used to separate _R. odorata_ and _R. chinensis._  
In addition to the rose flowers, the HS-SPME (CAR/PDMS fiber) techniques find applications in the analysis of rose aroma products such as concrete, absolute, and oil from _R. damascena_ Mill. [24]. Volatile compounds in the _R. damascena_ first rose oil and first rose water have been determined by HS-SPME-GC/MS, showing twenty-four and twenty-six volatile compounds in the former and latter [25]. The technique has promising applications in the analysis of the aroma of medicinal plants [26; 27; 28], rice [29], and food [13; 30; 31; 32].