Skip to main content
ISMPMI Congress 2025 Main banner
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.

Concurrent Session

Session: Concurrent Session: Microbe-mediated impacts on plant-parasite interactions

Volatile production and predatory wasp recruitment are indirect anti-herbivore defenses mediated by the pattern recognition receptor INR

Wednesday, July 16, 2025
16:25 - 16:35  
Location: Room P+Q

Abstract Text:

Legumes recognize the Herbivore-Associated Molecular Patters (HAMP) Inceptin11 (In11) via the Inceptin Receptor (INR), a pattern recognition receptor, to activate an herbivore-specific immune pathway. INR activation induces direct and indirect defenses including defense hormone biosynthesis, antinutritive proteins and predominant volatiles such as the homoterpene (E)-4,8-Dimethyl-1,3,7-nonatriene (DMNT).  To test the role of INR-mediated defenses in agricultural field settings, we developed Phaseolus vulgaris near-isogenic lines (NILs) with variation in a naturally occurring INR deletion. We screened P. vulgaris landraces for lack of In11-induced ethylene, and insensitivity was associated with an inr-1 allele, a 103 bp deletion in the LRR region of INR. inr-1 lines have impaired In11-induced MAPK phosphorylation and gene expression. Spodoptera exigua larvae growth rate increased 72.7% over a 5-day feeding time course on inr-1 lines. Similarly, the In11-induced volatiles, including DMNT production, of inr-1 lines are reduced to the level of mock treated plants (wounding alone). In field settings, pairs of NILs treated with physiological levels of In11 demonstrated a 40% reduction of attack by predatory Polybia sp wasps to sentinel Spodoptera caterpillars pinned to inr-1 plants, likely due to the inability to produce the volatile blend required for attraction. Our findings demonstrate that a pattern recognition receptor mediates tritrophic interactions in the field.