Ethylene functions as a suppressor of volatile production in rice

We examined the role of ethylene in the production of rice (Oryza sativa) volatile organic compounds (VOCs), which act as indirect defense signals against herbivores in tritrophic interactions. Rice plants were exposed to exogenous ethylene (1 ppm) after simulated herbivory, which consisted of mechanical wounding supplemented with oral secretions (WOS) from the generalist herbivore larva Mythimna loreyi. Ethylene treatment highly suppressed VOCs in WOS-treated rice leaves, which was further corroborated by the reduced transcript levels of major VOC biosynthesis genes in ethylene-treated rice. In contrast, the accumulation of jasmonates (JA), known to control VOCs in higher plants, and transcript levels of primary JA response genes, including OsMYC2, were not largely affected by ethylene application. At the functional level, flooding is known to promote internode elongation in young rice via ethylene signaling. Consistent with the negative role of ethylene on VOC genes, the accumulation of VOCs in water-submerged rice leaves was suppressed. Furthermore, in mature rice plants, which naturally produce less volatiles, VOCs could be rescued by the application of the ethylene perception inhibitor 1-methylcyclopropene. Our data suggest that ethylene acts as an endogenous suppressor of VOCs in rice plants during development and under stress.

Citation

Mujiono, K., Tohi, T., Sobhy, I. S., Hojo, Y., Ho, N. T., Shinya, T., & Galis, I. (2020). Ethylene functions as a suppressor of volatile production in rice. Journal of Experimental Botany, 71(20), 6491-6511. https://doi.org/10.1093/jxb/eraa341

Publisher

Oxford University Press

Journal

Journal of Experimental Botany

URI

http://hdl.handle.net/10034/629731

DOI

10.1093/jxb/eraa341

Type

Article

Language

en

Description

This is a pre-copyedited, author-produced version of an article accepted for publication in [Journal of Experimental Botany] following peer review. The version of record [Mujiono, K., Tohi, T., Sobhy, I. S., Hojo, Y., Ho, N. T., Shinya, T., & Galis, I. (2020). Ethylene functions as a suppressor of volatile production in rice. Journal of Experimental Botany, 71(20), 6491-6511] is available online at: https://academic.oup.com/jxb/article/71/20/6491/5874908 [https://doi.org/10.1093/jxb/eraa341]

ISSN

0022-0957

EISSN

1460-2431

Sponsors

We thank Atsushi Miyake (Okayama University) for help with development of GC-MS methods used for volatile measurements; Dr Hideyuki Matsuura (Hokkaido University) for providing deuterated jasmonate standards for LC-MS/MS; Dr Yasutaka Kubo (Okayama University) for providing 1-MCP; and Dr David Wari for checking the manuscript. This work was supported by Ohara Foundation and JSPS KAKENHI Grants (No. 24570026 and 16K08143 to IG, No. 18K05558 to TS). TT was supported by Pacific Leaders’ Educational Assistance for Development of State (Pacific-LEADS) from JICA (Japan International Cooperation Agency); ISS by the JSPS postdoctoral fellowship P13379; and KM by IsDB 4 in 1 Project by Ministry of Research, Technology, and Higher Education, Republic of Indonesia.

Additional Links

https://academic.oup.com/jxb/article/71/20/6491/5874908