Plant nucleotide-binding leucine-rich repeat immune receptor genes (NLRs) play an important role in plant defenses against pathogens, pathogenic nematodes, and piercing–sucking herbivores. However, little is known about their functions in plant defenses against chewing herbivores. Here, we identified a plasma membrane-localized coiled-coil-type NLR protein, OsPik-2-like, whose transcript levels were induced by the infestation of rice leaf folder (LF, Cnaphalocrocis medinalis) larvae, and by treatment with mechanical wounding. Knocking out OsPik-2-like in rice increased the LF-induced levels of jasmonic acid (JA) and jasmonoyl–isoleucine (JA-Ile), the activity of trypsin protease inhibitors (TrypPIs), and the basal levels of some flavonoids, which in turn decreased the performance of LF larvae. Moreover, knocking out OsPik-2-like reduced plant growth. These findings demonstrate that OsPik-2-like regulates the symbiosis between rice and LF by balancing plant growth and defense.

Vitellogenins are essential for the development and fecundity of insects, but these proteins may also betray them, as we show here. We found that the small N-terminal subunit of vitellogenins of the planthopper Nilaparvata lugens (NlVgN) triggers strong defense responses in rice plants when it enters the plant during feeding or oviposition by the insect. The defenses induced by NlVgN in plants not only decreased the hatching rate of N. lugens eggs, but also induced volatile emissions in rice plants, which rendered them attractive to a common egg parasitoid. VgN of other planthoppers were found to trigger the same defense responses in rice. We further show that VgN deposited during planthopper feeding compared to during oviposition induces a somewhat different response, probably targeting the appropriate developmental stage of the insect. The key importance of VgN for planthopper performance precludes possible evolutionary adaptions to prevent detection by rice plants.