| Title: | "The Fungus Raffaelea lauricola Modifies Behavior of Its Symbiont and Vector, the Redbay Ambrosia Beetle (Xyleborus Glabratus), by Altering Host Plant Volatile Production" |
| Author(s): | Martini X; Hughes MA; Killiny N; George J; Lapointe SL; Smith JA; Stelinski LL; |
| Address: | "Entomology and Nematology Department, North Florida Research and Education Center, University of Florida, 155 Experiment Road, Quincy, FL, 32351, USA. xmartini@ufl.edu. Entomology and Nematology Department, Citrus Research and Education Center, University of Florida, 700 Experiment Station Rd, Lake Alfred, FL, 33850, USA. xmartini@ufl.edu. School of Forest Resources and Conservation, University of Florida, 136 Newins-Ziegler Hall, Gainesville, FL, 32611-0410, USA. Plant Pathology Department, Citrus Research and Education Center, University of Florida, 700 Experiment Station Rd, Lake Alfred, FL, 33850, USA. Subtropical Insects and Horticultural Research Unit, United States Horticultural Research Laboratory, USDA-ARS, 2001 South Rock Rd., Fort Pierce, FL, 34945, USA. Entomology and Nematology Department, Citrus Research and Education Center, University of Florida, 700 Experiment Station Rd, Lake Alfred, FL, 33850, USA" |
| DOI: | 10.1007/s10886-017-0843-y |
| ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Linking) |
| Abstract: | "The redbay ambrosia beetle Xyleborus glabratus is the vector of the symbiotic fungus, Raffaelea lauricola that causes laurel wilt, a highly lethal disease to members of the Lauraceae family. Pioneer X. glabratus beetles infect live trees with R. lauricola, and only when tree health starts declining more X. glabratus are attracted to the infected tree. Until now this sequence of events was not well understood. In this study, we investigated the temporal patterns of host volatiles and phytohormone production and vector attraction in relation to laurel wilt symptomology. Following inoculations with R. lauricola, volatile collections and behavioral tests were performed at different time points. Three days after infection (DAI), we found significant repellency of X. glabratus by leaf odors of infected swamp bay Persea palustris as compared with controls. However, at 10 and 20 DAI, X. glabratus were more attracted to leaf odors from infected than non-infected host plants. GC-MS analysis revealed an increase in methyl salicylate (MeSA) 3 DAI, whereas an increase of sesquiterpenes and leaf aldehydes was observed 10 and 20 DAI in leaf volatiles. MeSA was the only behaviorally active repellent of X. glabratus in laboratory bioassays. In contrast, X. glabratus did not prefer infected wood over healthy wood, and there was no associated significant difference in their volatile profiles. Analyses of phytohormone profiles revealed an initial increase in the amount of salicylic acid (SA) in leaf tissues following fungal infection, suggesting that the SA pathway was activated by R. lauricola infection, and this activation caused increased release of MeSA. Overall, our findings provide a better understanding of X. glabratus ecology and underline chemical interactions with its symbiotic fungus. Our work also demonstrates how the laurel wilt pathosystem alters host defenses to impact vector behavior and suggests manipulation of host odor by the fungus that attract more vectors" |
| Keywords: | "Animals Ascomycota/*physiology Behavior, Animal/drug effects Coleoptera/drug effects/*physiology Gas Chromatography-Mass Spectrometry Lauraceae/*chemistry/metabolism/microbiology Plant Leaves/chemistry/metabolism/microbiology Symbiosis Volatile Organic Co;" |
| Notes: | "MedlineMartini, Xavier Hughes, Marc A Killiny, Nabil George, Justin Lapointe, Stephen L Smith, Jason A Stelinski, Lukasz L eng 2017/04/30 J Chem Ecol. 2017 May; 43(5):519-531. doi: 10.1007/s10886-017-0843-y. Epub 2017 Apr 28" |
