Silencing the alarm: an insect salivary enzyme closes plant stomata and inhibits volatile release
Journal
New Phytologist
Journal Volume
230
Journal Issue
2
Pages
793-803
Date Issued
2021
Author(s)
Chen Y
Chaverra-Rodriguez D
Heu C.C
Zainuddin N.B
Sidhu J.S
Peiffer M
Tan C.-W
Helms A
Kim D
Ali J
Rasgon J.L
Lynch J
Anderson C.T
Felton G.W.
Abstract
Herbivore-induced plant volatiles (HIPVs) are widely recognized as an ecologically important defensive response of plants against herbivory. Although the induction of this ‘cry for help’ has been well documented, only a few studies have investigated the inhibition of HIPVs by herbivores and little is known about whether herbivores have evolved mechanisms to inhibit the release of HIPVs. To examine the role of herbivore effectors in modulating HIPVs and stomatal dynamics, we conducted series of experiments combining pharmacological, surgical, genetic (CRISPR-Cas9) and chemical (GC-MS analysis) approaches. We show that the salivary enzyme, glucose oxidase (GOX), secreted by the caterpillar Helicoverpa zea on leaves, causes stomatal closure in tomato (Solanum lycopersicum) within 5 min, and in both tomato and soybean (Glycine max) for at least 48 h. GOX also inhibits the emission of several HIPVs during feeding by H. zea, including (Z)-3-hexenol, (Z)-jasmone and (Z)-3-hexenyl acetate, which are important airborne signals in plant defenses. Our findings highlight a potential adaptive strategy where an insect herbivore inhibits plant airborne defenses during feeding by exploiting the association between stomatal dynamics and HIPV emission. © 2021 The Authors. New Phytologist © 2021 New Phytologist Foundation
Subjects
effector; HIPV; insect herbivore; plant defense; stomata
SDGs
Other Subjects
caterpillar; enzyme activity; gene expression; genetic engineering; inhibition; saliva; stomatal conductance; vegetable; volatile organic compound; Glycine max; Helicoverpa zea; Hexapoda; Lycopersicon esculentum; volatile organic compound; animal; herbivory; insect; moth; plant stoma; Animals; Herbivory; Insecta; Moths; Plant Stomata; Volatile Organic Compounds
Type
journal article