# Chemical and Sensorial Characterization of Scented and Non-Scented Alstroemeria Hybrids
## 1 Introduction  
It is well known that the main function of floral scent is to attract pollinators [1], playing an important role in the idea of 'pollination syndrome' described in nature [2]. However, it is not completely clear how floral scent has the ability to attract specific pollinators, as it is for other visual cues such as flower morphology and colour [3; 4]. Many other functions have been attributed to floral scent, including the emission of certain compounds with the aim of repelling non-beneficial insects, for example, pollen and nectar 'thieves' or destructive insects [5]. Protection of reproductive organs from enemies through antimicrobial or antiherbivore activity attributed to some of the floral scent compounds have also been studied [6; 7; 8]. More recently, it was discovered that floral volatiles could function as cues to other plants, using them to gain information about their environment and respond by adjusting their phenotype [9].  
The composition of aroma has been studied in a vast diversity of species, finding different molecular compositions in terms of number and characteristic of the molecules involved in the scent [10]. Moreover, floral scent emission has been identified to respond to several factors such as light [11], temperature [12] and concentration of ozone in the air [13]. To determine the composition of the floral scent, the most widely used technique is gas chromatography coupled with a mass detector (GC-MS), finding that floral scent is dominated by volatile organic compounds (VCCs) such as monoterrepenoids, sesquiterpenoids, phenylpropanoids and benzenoid compounds [5]. Thus, a total of 1719 VOCs have been identified as composing the floral scent of 991 species [14]. An electronic nose has alsobeen useful to determine floral scent patterns in flowering stages [15]. However, not only instrumental evaluation has been described to evaluate floral scent; recent studies have also considered sensorial evaluation [16; 17] as a complement to a better understanding of this character.  
This study is focused on the evaluation of scent emitted by flowers of alstroemeria hybrids. The genus _Alstroemeria_ is native to South America and comprises 90 species [18], of which only one has been described as aromatic: _A. carryophyllaea_ Jacq. [19]. Many new cultivars have been developed, and nowadays alstroemeria is one of the most important species in the market of ornamental plants, especially as cut flowers [20], and more recently as pot plants [21]. However, floral scent is not a character that breeders have been particularly focused on, probably because this is a complex trait to breed, easily acquired and lost throughout generations [22]. Moreover, a negative correlation between the presence of floral scent and shorter vase life of the flower has been suggested. [23]. The floral scent of alstroemeria has been previously studied in the wild species _A. carryophyllaea_ Jacq., the cultivars 'Sweet Laura' and 'Ajax' [24], and several hybrids [16; 25] reporting terpenoid compounds as the most common VOCs detected, particularly monoterpenes. Moreover, a monoterpene synthase (_AlstroTPS_) has been characterised as responsible for the production of myrcene in alstroemeria flowers [24], being the only gene associated to floral scent reported so far in this species.  
Although floral scent of alstroemeria has already been described in some alstroemeria genotypes, as previously described, this is a very dynamic character that changes throughout generations. Thus, the aim of this study was focused on the characterization of the molecular composition of the scent of two new scented alstroemeria hybrids, resulting from crosses using _A. carryophyllaeae_ as parental line.