Maize OPR2 and LOX10 Mediate Defense against Fall Armyworm and Western Corn Rootworm by Tissue-Specific Regulation of Jasmonic Acid and Ketol Metabolism.

Foliage-feeding fall armyworm (FAW; ) and root-feeding western corn rootworm (WCR; ) are maize ( L.) pests that cause significant yield losses. Jasmonic acid (JA) plays a pivotal defense role against insects. 12-oxo-phytodienoic acid (12-OPDA) is converted into JA by peroxisome-localized OPDA reductases (OPR). However, little is known about the physiological functions of cytoplasmic OPRs. Here, we show that disruption of reduced wound-induced JA production and defense against FAW while accumulating more JA catabolites. Overexpression of in enhanced JA production and defense against beet armyworm (BAW; ). In addition, double mutants were more susceptible than either single mutant, suggesting that and uniquely and additively contributed to defense. In contrast to the defensive roles of and in leaves, single mutants did not display any alteration in root herbivory defense against WCR. Feeding on double mutants resulted in increased WCR mortality associated with greater herbivory-induced production of insecticidal death acids and ketols. Thus, and cooperatively inhibit the synthesis of these metabolites during herbivory by WCR. We conclude that and regulate JA-mediated resistance in leaves against FAW while suppressing insecticidal oxylipin synthesis in roots during WCR infestation.