| Title: | Mycorrhizae Alter Constitutive and Herbivore-Induced Volatile Emissions by Milkweeds |
| Address: | "Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA. armeier@umich.edu. Department of Entomology, University of Georgia, Athens, GA, 30602, USA. armeier@umich.edu. Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA" |
| DOI: | 10.1007/s10886-019-01080-6 |
| ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Linking) |
| Abstract: | "Plants use volatile organic compounds (VOCs) to cue natural enemies to their herbivore prey on plants. Simultaneously, herbivores utilize volatile cues to identify appropriate hosts. Despite extensive efforts to understand sources of variation in plant communication by VOCs, we lack an understanding of how ubiquitous belowground mutualists, such as arbuscular mycorrhizal fungi (AMF), influence plant VOC emissions. In a full factorial experiment, we subjected plants of two milkweed (Asclepias) species under three levels of AMF availability to damage by aphids (Aphis nerii). We then measured plant headspace volatiles and chemical defenses (cardenolides) and compared these to VOCs emitted and cardenolides produced by plants without herbivores. We found that AMF have plant species-specific effects on constitutive and aphid-induced VOC emissions. High AMF availability increased emissions of total VOCs, two green leaf volatiles (3-hexenyl acetate and hexyl acetate), and methyl salicylate in A. curassavica, but did not affect emissions in A. incarnata. In contrast, aphids consistently increased emissions of 6-methyl-5-hepten-2-one and benzeneacetaldehyde in both species, independent of AMF availability. Both high AMF availability and aphids alone suppressed emissions of individual terpenes. However, aphid damage on plants under high AMF availability increased, or did not affect, emissions of those terpenes. Lastly, aphid feeding suppressed cardenolide concentrations only in A. curassavica, and AMF did not affect cardenolides in either plant species. Our findings suggest that by altering milkweed VOC profiles, AMF may affect both herbivore performance and natural enemy attraction" |
| Keywords: | Animals Aphids/*physiology Asclepias/*chemistry/metabolism/parasitology Cardenolides/analysis Gas Chromatography-Mass Spectrometry Herbivory Host Microbial Interactions Host-Parasite Interactions Mycorrhizae/*physiology Plant Leaves/chemistry/metabolism/p; |
| Notes: | "MedlineMeier, Amanda R Hunter, Mark D eng 1256115/Directorate for Biological Sciences/ Dept. of Ecology and Evolutionary Biology Block Grant/University of Michigan/ Rackham Graduate Student Research Grant/University of Michigan/ Dept. of Ecology and Evolutionary Biology Matthaei Botanical Gardens Research Grant/University of Michigan/ Graduate Research Fellowship Program/National Science Foundation/ 2019/07/10 J Chem Ecol. 2019 Jul; 45(7):610-625. doi: 10.1007/s10886-019-01080-6. Epub 2019 Jul 8" |
