(<i>E</i>)‑β-Farnesene Protects\nRice from Rice Striped Stem Borer Attack by Inhibiting Its Beneficial\nGut Microbes

Herbivores harbor gut microbes that\naffect their development and\ncontribute to their nutrition, reproduction, and survival. Plant defenses\ncould target the herbivore’s beneficial gut microbes, but this\nhas not been well studied in rice. In this context, we identified\na rice terpene synthase gene, Os04g0341500. It was strongly induced\nafter feeding by rice striped stem borers (SSB, Chilo\nsuppressalis), and it can catalyze the (<i>E</i>)-β-farnesene (Eβf) synthesis. When added to artificial\ndiets, Eβf impaired the development and survival of SSB larvae.\nHigh-throughput amplicon sequencing revealed that SSB fed on Eβf\nwere decreased in beneficial gut microbes, compared to those feeding\non the corresponding control feed. In vitro feeding of Eβf suggested\nthat this antimicrobial sesquiterpene directly inhibited the growth\nof SSB gut microbes. The present study suggested that the Eβf-induced\ndecrease of relative abundance of gut microbes potentially impairs\nlarval development and survival in SSB.