| Title: | Phytohormones in Fall Armyworm Saliva Modulate Defense Responses in Plants |
| Author(s): | Acevedo FE; Smith P; Peiffer M; Helms A; Tooker J; Felton GW; |
| Address: | "Department of Entomology, Pennsylvania State University, University Park, PA, USA. floredith.acevedo@gmail.com. Huck Institute of the Life Sciences, Pennsylvania State University, University Park, PA, USA. Department of Entomology, Pennsylvania State University, University Park, PA, USA. Department of Entomology, Texas A&M, College Station, TX, USA. Department of Entomology, Pennsylvania State University, University Park, PA, USA. gwf10@psu.edu" |
| DOI: | 10.1007/s10886-019-01079-z |
| ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Linking) |
| Abstract: | "Insect herbivory induces plant defense responses that are often modulated by components in insect saliva, oral secretions or regurgitant, frass, or oviposition fluids. These secretions contain proteins and small molecules that act as elicitors or effectors of plant defenses. Several non-protein elicitors have been identified from insect oral secretions, whereas studies of insect saliva have focused mainly on protein identification. Yet, insect saliva may also contain non-protein molecules that could activate defense responses in plants. The goal of this study was to identify non-protein plant defense elicitors present in insect saliva. We used the fall armyworm (FAW), Spodoptera frugiperda and its host plants tomato, maize, and rice as a model system. We tested the effect of protein-digested saliva or non-protein components on herbivore-induced defense responses in maize, rice and tomato. We identified phytohormones in FAW saliva using high performance liquid chromatography coupled with mass spectrometry. The results of this study show that non-protein components in FAW saliva modulated defense responses in different plant species. The saliva of this insect contains benzoic acid, and the phytohormones jasmonic acid, salicylic acid, and abscisic acid at concentrations of <5 ng per mul of saliva. Plant treatment with similar phytohormone quantities detected in FAW saliva upregulated the expression of a maize proteinase inhibitor gene in maize, and down-regulated late herbivore-induced defenses in tomato plants. We conclude that FAW saliva is a complex fluid that, in addition to known enzymatic plant defense elicitors, contains phytohormones and other small molecules" |
| Keywords: | "Animals Chromatography, High Pressure Liquid Gene Expression Regulation, Plant/drug effects Herbivory Larva/metabolism Solanum lycopersicum/metabolism/parasitology Mass Spectrometry Plant Growth Regulators/*analysis/pharmacology Plant Leaves/metabolism/pa;" |
| Notes: | "MedlineAcevedo, Flor Edith Smith, Philip Peiffer, Michelle Helms, Anjel Tooker, John Felton, Gary W eng AFRI 2017-67013-26596/ Department of Agriculture/ IOS-1645548/National Science Foundation/ PEN04576/Hatch Project Grant/ 2013-CAS Graduate Student Award/Pennsylvania State University/ 2014-Monsanto Research Grant/Entomological Society of America/ 2019/06/21 J Chem Ecol. 2019 Jul; 45(7):598-609. doi: 10.1007/s10886-019-01079-z. Epub 2019 Jun 20" |
