Native to South America, Alstroemeria flowers are known for their colourful tepals, and Alstroemeria hybrids are an important cut flower. However, in common with many commercial cut flowers, virtually all the commercial Alstroemeria hybrids are not scented. The cultivar ‘Sweet Laura’ is one of very few scented commercial Alstroemeria hybrids. Characterization of the volatile emission profile of these cut flowers revealed three major terpene compounds: (E)-caryophyllene, humulene (also known as α-caryophyllene), an ocimene-like compound, and several minor peaks, one of which was identified as myrcene. The profile is completely different from that of the parental scented species A. caryophyllaea. Volatile emission peaked at anthesis in both scented genotypes, coincident in cv. ‘Sweet Laura’ with the maximal expression of a putative terpene synthase gene AlstroTPS. This gene was preferentially expressed in floral tissues of both cv. ‘Sweet Laura’ and A. caryophyllaea. Characterization of the AlstroTPS gene structure from cv. ‘Sweet Laura’ placed it as a member of the class III terpene synthases, and the predicted 567 amino acid sequence placed it into the subfamily TPS-b. The conserved sequences R²⁸(R)X₈W and D³²¹DXXD are the putative Mg²⁺-binding sites, and in vitro assay of AlstroTPS expressed in Escherichia coli revealed that the encoded enzyme possesses myrcene synthase activity, consistent with a role for AlstroTPS in scent production in Alstroemeria cv. ‘Sweet Laura’ flowers.

The main function of floral scent is to attract and guide pollinators, but it is also an important character in the ornamental plant industry. Several studies have considered the chemical evaluation of floral scent during vase life, but only a few have considered sensorial analysis of this character, which is a very important quality trait for the marketing of ornamental plants. This study focused on assessing the floral scent of three fragrant cut flowers of high economic importance: Lilium, chrysanthemum, and freesia. Eighty individuals were included in a sensorial analysis where the attributes of floral scent liking and intensity were evaluated. The composition of the floral scent was analyzed through the collection of headspace followed by gas chromatography-mass spectrometry (GC-MS). The floral scents of oriental lily and freesia were perceived as more intense, compared to chrysanthemum. A total of 28 volatile compounds were detected and the monoterpenes β-pinene (40.7 ± 1.8 μg·L⁻¹), β-cis-ocimene (5552 ± 990 μg·L⁻¹), and linalool (11,800 ± 220 μg·L⁻¹) were the major volatile organic compounds (VOCs) present in chrysanthemum, lilium, and freesia, respectively. The results presented in this study confirm that the concentration and abundance of volatile compounds is not directly related to the human perception of floral scent.

Alstroemeriais a genus native to South America from which many varieties of ornamental plants have been developed and introduced into the market. Interspecific hybridization followed by embryo rescue has been one of the most common breeding techniques to obtain new varieties. This study was aimed at obtaining alstroemeria hybrids through interspecific crosses using novel scented parental lines and assessing these hybrids. A total of 3669 embryos were rescued, from which 18 flowering plants were morphologically evaluated. Flower stem length ranged from 25 (14E07) to 83 cm (14A11) and most of the flowers showed pink/white colors with stripes over the inner tepals. Only 3 hybrids were perceived as scented and one of them (14E08) was evaluated through GC-MS analysis, detecting 9 VOCs, all of them monoterpenes. Molecular analysis using RAPD markers clustered two main groups: (A) hybrids withA. pelegrinaas parental line and (B) hybrids coming from the crossing UC05 × C3 and its reciprocal. Moreover through this analysis was possible to subcluster hybrids coming from different seasons. A protocol for obtaining alstroemeria hybrids was successfully developed for this species using molecular and phenotypic evaluation to provide information about their pedigree and to spot those traits which are attractive for the ornamental plant market.