Summary

Herbivore-induced plant volatiles (HIPVs) are known to be perceived by neighboring plants, resulting in induction or priming of chemical defenses. There is little information on the defense responses that are triggered by these plant-plant interactions and the phenomenon has rarely been studied in rice. Using chemical and molecular analyses in combination with insect behavioral and performance experiments we studied how volatiles emitted by rice plants infested by the striped stem borer (SSB)  Chilo suppressalis affect defenses against this pest in conspecific plants. Compared to rice plants exposed to the volatiles from uninfested plants, plants exposed to SSB-induced volatiles showed enhanced direct and indirect resistance to SSB. When subjected to caterpillar damage, the HIPV-exposed plants showed increased expression of jasmonic acid (JA) signaling genes, resulting in JA accumulation and higher levels of defensive proteinase inhibitors. Moreover, plants exposed to SSB-induced volatiles emitted larger amounts of inducible volatiles and were more attractive to the parasitoid  Cotesia chilonis . By unraveling the factors involved in HIPV-mediated defense priming in rice we reveal a key defensive role for proteinase inhibitors. These findings pave the way for novel rice management strategies to enhance the plant’s resistance to one of its most devastating pests.

New Phytologist, IF: 10.323

https://doi.org/10.1111/nph.18548