The brown planthopper, Nilaparvata lugens Stål (Hemiptera: Delphacidae), is a notorious pest on rice in Asia and has evolved serious resistance to traditional chemical insecticides in recent years. Triflumezopyrim, a newly commercialized mesoionic insecticide, exhibited an excellent control effect on sucking insects, including N. lugens. However, the effects of triflumezopyrim on the reproduction of N. lugens have not yet been fully elucidated. In this study, we investigated the impacts of different concentrations of triflumezopyrim (LC₁₀, LC₅₀ and LC₉₀) on the reproduction and the reproduction related genes of N. lugens exposure to the insecticide via systemic and contact route. The results indicated that the preoviposition periods of N. lugens females in the LC₅₀ and LC₉₀ triflumezopyrim-treated groups (♀ t × ♂ t) were prolonged in contact toxicity treatment, compared with control (acetone treatment). The fecundities for three pair combinations (♀ c ×♂ t, ♀ t ×♂ c and ♀ t ×♂ t) treated with LC₅₀ and LC₉₀ concentrations of triflumezopyrim showed a significant decrease compared to water/acetone-treated control via contact and systemic route. No significant effects of LC₁₀ triflumezopyrim on preoviposition period and fecundity were found in contact and systemic toxicity treatments. However, the triflumezopyrim did not influence the egg hatchability. By microscope observation, the LC₅₀ and LC₉₀ triflumezopyrim impended the ovarian development in females. qRT-PCR analysis showed that the vitellogenin (NlVg) relative expression level of female adults exposed to LC₅₀ and LC₉₀ triflumezopyrim decreased by 30.3 – 39.5% in two toxicity treatments. The titers of another reproduction related hormones juvenile hormone III (JH III) in LC₅₀ and LC₉₀ triflumezopyrim-treatments were 27.4% and 25.8% lower than control in contact toxicity treatment and 27.08% and 37.18% lower than control in systemic toxicity treatment. In summary, these results suggested that the median lethal and high lethal concentrations of triflumezopyrim inhibited the reproduction and reduced the expression of NlVg and JH III in N. lugens. This study provided a reference for the efficient and scientific utilization of triflumezopyrim in the field.

褐飞虱Nilaparvata lugens Stål（半翅目：Delphacidae）是亚洲一种臭名昭著的水稻害虫，近年来对传统化学杀虫剂产生了严重的抗药性。Triflumezopyrim 是一种新近商业化的中离子杀虫剂，对包括N. lugens在内的吸吮昆虫表现出极好的防治效果。然而，三氟甲嘧啶对褐飞虱繁殖的影响尚未完全阐明。在本研究中，我们研究了不同浓度的三氟嘧啶（LC ₁₀、LC ₅₀和LC ₉₀）对褐飞虱繁殖和繁殖相关基因的影响通过全身和接触途径接触杀虫剂。结果表明，与对照组（丙酮处理）相比，接触毒性处理组（♀ t × ♂ t）在LC ₅₀和LC ₉₀三氟嘧啶处理组中雌性褐飞虱产卵前时间延长。三对组合（♀ c ×♂ t、♀ t ×♂ c 和♀ t ×♂ t）经LC ₅₀和LC ₉₀浓度的三氟嘧啶处理的繁殖力与水/丙酮处理的对照相比显着降低。系统性途径。LC ₁₀没有显着影响在接触和全身毒性处理中发现了三氟甲嘧啶对产卵前期和繁殖力的影响。然而，三氟甲嘧啶不影响卵孵化率。通过显微镜观察，LC ₅₀和 LC ₉₀三氟甲嘧啶阻碍了女性的卵巢发育。qRT-PCR 分析表明，在两种毒性处理中，暴露于 LC ₅₀和 LC ₉₀三氟嘧啶的雌性成年人的卵黄蛋白原 ( NlVg ) 相对表达水平降低了 30.3-39.5%。LC ₅₀和 LC ₉₀中另一种生殖相关激素保幼激素 III (JH III) 的滴度三氟嘧啶处理在接触毒性处理中分别比对照低 27.4% 和 25.8%，在全身毒性处理中比对照低 27.08% 和 37.18%。总之，这些结果表明，三氟嘧啶的中等致死浓度和高致死浓度抑制了褐飞虱的繁殖并降低了NlVg和 JH III的表达。该研究为三氟嘧啶在田间的高效科学利用提供了参考。