## 1 Introduction  
As commercial fruits with popular flavor, grapes (_Vitis vinifera_ L.), are widely planted in arid and semi-arid areas [1]. They possess high nutritional value owing to the rich contents of carbohydrates, organic acids, and minerals [2]. Apart from their everyday use as a fresh fruit for eating, grapes can be processed into a number of other products, such as raisins, wine and juice, in which flavor is one of the most important commercial indexes. Therefore, analyzing grape volatiles, which are the predominant contributors to the fruity notes and flavors of grape products [3], is necessary. Grape volatiles, derived from several pathways and belonging to different chemical groups, are multifarious and vary from species to species [4]. Specifically, the varietal volatile profiles of grapes are constituted by monoterpenoids, sesquiterpenoids and C\({}_{13}\) norisoprenoids [5]. The bound aroma fraction in most grape varieties does not directly provide the flavor. On the contrary, crushing or processing on grapes transforms their volatiles into odor-active forms [6], including C\({}_{6}\) compounds, which can provide wine with a strong herbaceous flavor [7], terpenes, C\({}_{13}\) norisoprenoids, benzenoid compounds, and aliphatic alcohols in the skin of grapes [3]. Moreover, aroma molecules could be formed by salivary or bacterial enzymes from two odorless precursors, glutathionyl and cysteinyl [8]. Consequently, the flavor of grape products is affected by free aroma fraction embedded in fresh grapes combined with aroma production and transformation during processing and consumption. Growing in China, grapes in different regions enjoy various cultivational environments. Some volatiles are reported as plant secondary metabolites and their syntheses are easily affected by climate conditions [9]. As investigated, low water treatment in 'Cabernet Sauvignon' grapes produced desirable aromas that differed from the unfavorable herbaceous-related aromas induced by irrigation treatment [10]. Comparing the volatile profiles of grapes in different environmental conditions, terpenoids were higher in samples that grew at high altitude and room temperature (25 \({}^{\circ}\)C) [5]. Warm conditions could preserve more monoterpenes than cool conditions in different grape varieties from several countries [11]. In regions with higher temperature and humidity, norisoprenoids were more abundant in grapes [11]. Furthermore, (E)-\(\beta\)-damascenone, \(\beta\)-ionone, hexanal, 2-hexanol, (Z)-3-hexenol and (E)-2-hexenol were highly correlated with various environmental parameters [11]. Moreover, volatiles are regarded as stress-responsive compounds in plants. For example, both long-term heat and heat-shock stresses were shown to enhance the elicitation of lipoxygenase and glucosinolate volatiles in _Brassica nigra_[12]. A group of specific volatiles, including mono- and sesquiterpenes, were found to be stress-responsive and played important roles in plant stress tolerance [13]. Recently, several studies indicated that the stress-responsive roles of volatiles were modulated by groups of TFs, which expanded our knowledge on the modulative mechanism of volatiles under stress. Previously, transcription repressor TPLs were proved to mediate volatile organic compounds in tobacco [14]. In tea, low temperature combined with wounding stress stimulated CsMYC2, which was involved in jasmonic-acid signaling, thus facilitating the biosynthesis of indole [15]. As noted, volatile profiles in grapes are dependent on growing conditions and are stress-responsive. However, how grape volatiles are regulated by surrounding conditions has been less comprehensively studied. Therefore, we selected grapes grown in two regions with various climate conditions in China to investigate the diverse composition of their volatiles.