Between plant and diurnal variation in quantities and ratios of volatile compounds emitted by Vicia faba plants.
Ratios of volatile phytochemicals potentially offer a means for insects to recognise their host-plant species. However, for this to occur ratios of volatiles would need to be sufficiently consistent between plants and over time to constitute a host-characteristic cue. In this context we collected headspace samples from Vicia faba plants to determine how consistent ratios of key volatile phytochemicals used in host location by one of its insect pests, the black bean aphid, Aphis fabae, were. These were (E)-2-hexenal, (Z)-3-hexen-1-ol, 1-hexanol, benzaldehyde, 6-methyl-5-hepten-2-one, octanal, (Z)-3-hexen-1-yl acetate, (R)-linalool, methyl salicylate, decanal, undecanal, (E)-caryophyllene, (E)-beta-farnesene, (S)-germacrene D, and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, which had previously been found to be electrophysiologically and behaviourally active to A. fabae. Although the quantities of volatiles produced by V. faba showed large between plant and diurnal variation, correlations between quantities of compounds indicated that the ratios of certain pairs of volatiles were very consistent. This suggests that there is a host-characteristic cue available to A. fabae in the form of ratios of volatiles.
Rothamsted Research, Biological Chemistry Department, Harpenden, Hertfordshire AL52JQ, United Kingdom.
Ben
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Webster
Salvador
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Gezan
Toby
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Bruce
Jim
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Hardie
John
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Pickett
D000818:Animals; D001042:Aphids; D014644:Genetic Variation; D006790:Host-Parasite Interactions; D017440:Photoperiod; D010935:Plant Diseases; D031307:Vicia faba / Q000235:genetics / Q000378:metabolism*; D055549:Volatile Organic Compounds / Q000378:metabolism*
D055549:Volatile Organic Compounds