SummaryTerpene synthases (TPSs) are key enzymes in terpenoids synthesis of plants and play crucial roles in regulating plant defence against pests and diseases. Here, we report the functional characterization of OsTPS19 and OsTPS20, which were upregulated by the attack of brown planthopper (BPH). BPH female adults performed concentration‐dependent behavioural responses to (S)‐limonene showing preference behaviour at low concentrations and avoidance behaviour at high concentrations. Overexpression lines of OsTPS19 and OsTPS20, which emitted higher amounts of the monoterpene (S)‐limonene, decreased the hatching rate of BPH eggs, reduced the lesion length of sheath blight caused by Rhizoctonia solani and bacterial blight caused by Xanthomonas oryzae. While knockout lines of OsTPS19 and OsTPS20, which emitted lower amounts of (S)‐limonene, were more susceptible to these pathogens. Overexpression of OsTPS19 and OsTPS20 in rice plants had adverse effects on the incidence of BPH, rice blast, and sheath blight in the field and had no significant impacts on rice yield traits. OsTPS19 and OsTPS20 were found to be involved in fine‐tuning the emission of (S)‐limonene in rice plants and play an important role in defence against both BPH and rice pathogens.

中文翻译：

---

柠檬烯增强水稻对刺吸式食草动物和水稻病原体的抵抗力


摘要萜烯合酶（TPS）是植物萜类化合物合成的关键酶，在调节植物抵御病虫害方面发挥着至关重要的作用。在这里，我们报告了 OsTPS19 和 OsTPS20 的功能特征，它们因褐飞虱 (BPH) 的攻击而上调。 BPH 女性成虫对 (S)-柠檬烯表现出浓度依赖性行为反应，在低浓度下表现出偏好行为，在高浓度下表现出回避行为。 OsTPS19和OsTPS20的过表达品系释放出较高量的单萜(S)-柠檬烯，降低了BPH卵的孵化率，缩短了立枯丝核菌引起的纹枯病和米黄单胞菌引起的白叶枯病的病斑长度。而 OsTPS19 和 OsTPS20 的敲除品系释放的 (S)-柠檬烯含量较低，因此更容易受到这些病原体的影响。水稻中OsTPS19和OsTPS20的过表达对田间褐飞虱、稻瘟病和纹枯病的发生有不利影响，但对水稻产量性状没有显着影响。人们发现 OsTPS19 和 OsTPS20 参与微调水稻植物中 (S)-柠檬烯的排放，并在防御 BPH 和水稻病原体方面发挥重要作用。