Volatile profile of Calycanthus occidentals seeds and evidence for a diverse range of semiochemicals for vespicochory by pestiferous Vespula pensylvanica

Authors: Beck, John; BURGE, DYLAN - University Of California; Willms, Steve; Baig, Nausheena

Submitted to: Trends in Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/9/2019
Publication Date: 5/23/2019
Citation: Beck, J.J., Burge, D.O., Willms, S.D., Baig, N. 2019. Volatile profile of Calycanthus occidentals seeds and evidence for a diverse range of semiochemicals for vespicochory by pestiferous Vespula pensylvanica. Trends in Entomology. 15:15-22.

Interpretive Summary: The family of Vespidae is large and diverse with both social and solitary wasps that reside in an array of nesting sites. In addition to being considered a nuisance insect, many of the species are known as plant pollinators. A little known role of select vespid wasps is dispersers of elaiososome-bearing seeds. Elaiosomes are a fleshy appendage attached to some seeds, and are known to contain beneficial nutritional benefits. This relationship is considered mutualistic given the long-range dispersal benefit to the seed and the nutritional benefit to the wasps. Some fatty-type compounds have been shown to be responsible for attracting wasps to some elaiososome-bearing seeds. Recent observations in northern California indicated that western yellowjacket, Vespula pensylvanica, procured and transported seeds from the western spicebush (Calycanthus occidentalis). Analysis of odors collected from C. occidentalis and subsequent biological assays studies provided a number of compounds from a range of chemical classes that elicited responses from V. pensylvanica antennae. Field trapping studies performed near V. pensylvanica nests in northern California with select odors identified from the seeds confirmed mild attractancy of several compounds and suggestive repellency of another.

Technical Abstract: Vespidae represents a large and diverse family and comprises both social and solitary wasps that reside in an array of nesting sites. In addition to being considered a nuisance insect, many of the species are known as plant pollinators. Discovered approximately 30 years ago and gaining in the number of identified wasps is the little known role of select vespid wasps as dispersers of elaiososome-bearing seeds. This relationship is considered mutualistic given the long-range dispersal benefit to the seed and the nutritional benefit to the wasps. Long-chain hydrocarbons have been shown to be responsible for attracting wasps to some elaiososome-bearing seeds. Recent observations in northern California indicated that western yellowjacket, Vespula pensylvanica, procured and transported seeds (achenes) from the western spicebush (Calycanthus occidentalis). Analysis of volatiles collected from C. occidentalis and subsequent electrophysiological studies provided a number of compounds from a range of chemical classes that elicited responses from V. pensylvanica antennae. Field trapping studies performed near V. pensylvanica nests in northern California with select volatiles from the seeds confirmed mild attractancy of several compounds and suggestive repellency of another.