Flowering Stage and Daytime Affect Scent Emission of Malus ioensis “Prairie Rose”

Abstract

Flowering crabapple is an important ornamental flower. It is vital to understand the floral scent properties and the associated release dynamics for carrying out fragrant flower breeding or floral regulation of crabapple. Static headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry was used to detect the volatile compounds in Malus ioensis “Prairie Rose” flowers at different flowering stages and at different day-night time. The results showed that methylheptenone, phenylethanol, geranylacetone, 2-(4-methoxyphenyl)ethanol, α-cedrene were the major compounds in M. ioensis “Prairie Rose”, but the compounds released during different stages and different day-night time were significantly different (P < 0.0001). A total of 25 volatile compounds were identified from the four flowering stages. The floral scents in the initial and flowering stages were the most similar (dissimilarity 0.21). The main compounds in these two stages were geranylacetone and methylheptenone, and the contents of geranylacetone and phenylethanol were positively correlated with the flowering stages. From the bud stage to the end of flowering, the total amount of volatile compounds released showed an initial increase followed by a decrease and the amounts of compounds released during the initial flowering stage were the highest. The aliphatic and benzenoids content was significant higher in the daytime than at night. A total of 15 compounds were detected in the five time periods. Methylheptenone and phenylethanol were particularly released in the 10:00–12:00 and 15:00–17:00 time periods. There were only three common compounds among the five time periods and the types of flower volatiles released during the daytime were obviously higher than those released at night. From the nocturnal to diurnal, the amount of flower volatiles released first increased, then decreased, and the release reached a peak between 10 am and 12 noon, which was consistent with the pollination biological characteristics of Malus flowers. Our findings are important for understanding the mechanism of insect visits to crabapple and the regulation of crabapple flower scent.

Floral scent compounds and emission patterns of three Styrax species

“…Twenty-four, twenty-two and twenty-two compounds were identified in three Styrax species at three flowering stages, and α-pinene, ocimene and myrcene were common volatiles. The total content of terpenes in S. japonicus revealed a 'V' trend, which was in agreement with the research conducted by Fan et al (2019). However, terpenes content descended continuously in S. grandiflora and S. calvescens.…”

Headspace Volatiles and Endogenous Extracts of Prunus mume Cultivars with Different Aroma Types

“…The study showed that the main compounds of P. mume cultivars from the four aroma types were phenylpropanoids/benzenoids, which is consistent with many ornamental plants, such as M. ioensis [ 13 ], Rosa odorata and R. chinensis [ 24 ], P . axillaris [ 25 ], and Luculia pinceana [ 26 ].…”

“…The floral scent is formed by the interaction of various volatile organic components. In addition, it has been widely accepted that compounds with high OAV contribute more to the aroma of the sample [ 13 , 36 ]. The compounds with higher content and aroma value could be regarded as characteristic components, while the components with lower content and higher odor threshold had a weaker influence on the floral scent [ 2 , 37 ].…”

“…As the most potent contributor, its aroma attributes (fruity odor impressions) may match the sensorial properties of the sweet-scented type. Since methyl salicylate with spicy odor and pentyl acetate with fruity aroma characteristics had higher content in light-scented type [ 13 , 43 ], it is speculated that they may be related to the formation of light-scented type.…”

“…There are three methods to extract the volatile compounds, such as extraction, distillation, and headspace methods [ 12 ]. At present, most of the volatile compounds in ornamental flowers are determined by headspace solid-phase microextraction (HS-SPME), including Malus ioensis [ 13 ], Chrysanthemum [ 14 ], and Iris [ 2 ]. HS-SPME can accurately analyze the volatile samples, enrich and separate the aroma components with a low threshold, which is more specific, simple and reliable to living plants.…”