Silencing the alarm an insect salivary enzyme closes plant stomata and inhibits volatile release

• Published in: The New phytologist Vol. 230; no. 2; pp. 793 - 803
• Main Authors: Lin, Po-An, Chen, Yintong, Chaverra-Rodriguez, Duverney, Heu, Chan Chin, Zainuddin, Nursyafiqi Bin, Sidhu, Jagdeep Singh, Peiffer, Michelle, Tan, Ching-Wen, Helms, Anjel, Kim, Donghun, Ali, Jared, Rasgon, Jason L., Lynch, Jonathan, Anderson, Charles T., Felton, Gary W.
• Format: Journal Article
• Language: English
• Published: England Wiley 01.04.2021; Wiley Subscription Services, Inc; John Wiley and Sons Inc
• Subjects: Acetates; Acetic acid; Allelochemicals; Animals; CRISPR; CRISPR-Cas systems; Defensive behavior; Dynamics; effector; Emission; Emissions; Enzymes; Gene editing; Glucose oxidase; Glycine (amino acid); Glycine max; Helicoverpa zea; Herbivores; Herbivory; HIPV; insect herbivore; Insecta; Insects; Moths; phytophagous insects; plant defense; Plant Stomata; Solanum lycopersicum; Soybeans; Stomata; stomatal movement; Tomatoes; Volatile compounds; Volatile Organic Compounds; Volatiles; stomata; effector; plant defense; insect herbivore; HIPV
• ISSN: 0028-646X; 1469-8137; 1469-8137
• DOI: 10.1111/nph.17214

• 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.