Scents in orchards: floral volatiles of four stone fruit crops and their attractiveness to pollinators

• Published in: Chemoecology 2018-04, Vol.28 (2), p.39-49
• Main Authors: El-Sayed, Ashraf M., Sporle, Andrew, Colhoun, Kate, Furlong, Jess, White, Robyn, Suckling, David M.
• Format: Article
• Language: English
• Subjects: Agricultural economics; Attraction; Benzaldehyde; Biomedical and Life Sciences; Chemical stimuli; Crops; Ecology; Economic importance; Entomology; Flowers; Food resources; Foraging habitats; Fruit crops; Fruits; Gas chromatography; Geographical variations; Headspace; Life Sciences; Mass spectrometry; Mass spectroscopy; Nature Conservation; Orchards; Original Article; Plant reproduction; Pollination; Pollinators; Prunus; Prunus armeniaca; Prunus avium; Prunus domestica; Prunus persica; Scents; Stone; Volatile compounds; Volatiles
• ISSN: 0937-7409; 1423-0445
• DOI: 10.1007/s00049-018-0254-8

Stone fruit crops grow in various regions around the world and are highly valued for their nutritional content, delicious taste, and economic importance, with an annual worldwide production of up to 42 million tonnes. In spite of their importance as a food resource, little is known about the chemistry of the floral volatiles of these crops, especially in relation to plant–pollinator interactions. In this study, the floral volatiles from four major stone fruit crops (apricot, Prunus armeniaca L.; plum, Prunus domestica L.; cherry, Prunus avium L.; and peach, Prunus persica L.) were collected and analysed by coupled gas chromatography/mass spectrometry (GC/MS). This was followed by several field trials, where selected floral volatiles were tested for attractiveness to flower visitors and pollinators. Twenty-six floral volatile compounds were identified in the headspace of the four Prunus spp. Benzaldehyde was present in the headspace of all four species. The norisoprenoid 4-oxoisophorone and lilac aldehyde were the main compounds in the headspace of P. armeniaca, P. domestica , and P. avium . The floral headspace of P. persica was distinct from the other three Prunus species, with 3,5-dimethoxytoluene being the most prominent compound (> 95%). In the field trapping trials, 4-oxoisophorone was attractive to various flower visitor species in a number of habitats when tested alone or in combination with benzaldehyde. Similarly, 3,5-dimethoxytoluene attracted several flower visitor species when tested alone or in combination with benzaldehyde. Our finding suggests that chemical cues are an important signal in plant–pollinator interactions in the four stone fruit species. This work provides the first detailed analysis of the floral volatiles of these important crops, especially in the context of plant–pollinator interactions. The floral compounds identified in this study could be used to enhance pollination of these important crops, either by direct application in the field (i.e. slow-release device) to enhance pollinator foraging or by training pollinators on such signature compounds to enhance flower visitation.