Knocking out a wall-associated kinase gene enhances rice resistance to planthoppers in the field

Wall-associated kinases (WAKs) play an important role in regulating plant growth, development, as well as responses to abiotic stresses and pathogens. However, their roles in plant resistance to herbivorous insects were largely unclear.

We cloned a rice WAK gene, OsWAK28, and found that its expression was induced by the infestation of the brown planthopper (BPH, Nilaparvata lugens) but suppressed by mechanical wounding and treatment with methyl jasmonate (MeJA), salicylic acid (SA), or abscisic acid (ABA). Knocking out OsWAK28 enhanced the levels of BPH-induced jasmonic acid, jasmonoyl-L-isoleucine, ABA, SA, and H₂O₂ in rice. Moreover, knocking out OsWAK28 in rice enhanced the levels of three cell wall components (hemicellulose, cellulose and lignin) and four defense compounds (schaftoside+isoschaftoside, eriodictyol 7-O-glucoside, p-coumaroyl-feruloyl putrescine, and ferulic acid), which subsequently enhanced the resistance of rice to planthoppers in the greenhouse and field.

Our results demonstrate that OsWAK28 is involved in the interaction between rice and planthoppers, negatively regulating rice resistance to planthoppers. The work provides a potential new approach for breeding rice varieties resistant to planthoppers. © 2026 Society of Chemical Industry.