【摘要】 【目的】探究吡虫啉预处理水稻对稻瘿蚊的抑制效应及其对水稻次生代谢物总酚含量的影响，为解析广西稻区稻瘿蚊种群衰退机制提供新的理论支撑。【方法】采用稻瘿蚊致害性国际标准苗期筛选法、害虫生物学常规观测法和分光光度法等系统测定吡虫啉预处理水稻不同间隔时间接入稻瘿蚊后对水稻标葱率、害虫产卵量、卵孵化率及幼虫发育进程的抑制效应，并分析水稻次生代谢物总酚含量的动态变化及其与水稻标葱率之间的关系。【结果】吡虫啉拌种（药后5～25 d接入稻瘿蚊）和喷雾（药后1～20 d接入稻瘿蚊）均极显著抑制稻瘿蚊侵染（P<0.01，下同），水稻标葱率分别为0～3.95%和0～4.51%。拌种药后13 d接虫，稻瘿蚊产卵量显著降低（P<0.05，下同），为42.33粒/10头，但卵孵化率高达69.32%，极显著高于清水对照处理；药后18～23 d接虫，稻瘿蚊产卵量和卵孵化率与对照无显著差异（P>0.05，下同）。喷雾药后5 d接虫，稻瘿蚊产卵量（21.00粒/10头）极显著低于对照，但药后10～15 d接虫，稻瘿蚊产卵量与清水对照处理无显著差异。拌种13 d或喷雾5 d后接虫的稻瘿蚊幼虫发育受阻，接虫后9～19 d拌种组幼虫体长0.43～0.59 mm、喷雾组幼虫体长0.43～0.48 mm、清水对照组幼虫体长0.82～2.47 mm，至接虫后22 d时药剂处理组幼虫仍处于低龄发育阶段，而对照组已完成化蛹，发育进程差异极显著。进一步分析发现，拌种和喷雾2种施药处理均诱导水稻总酚含量增多，但整体随时间推移逐渐递减，且其动态变化与水稻标葱率呈显著负相关。【结论】吡虫啉预处理通过诱导水稻总酚积累形成早期抗虫防御机制，实现对稻瘿蚊种群动态的间接调控。更多还原

【Abstract】 【Objective】To investigate the inhibitory effect of imidacloprid pretreatment on rice against the rice gall midge(Orseolia oryzae) and its impact on the total phenolic content of secondary metabolites in rice, which could provide new theoretical reference for elucidating the population decline mechanism of the rice gall midge in Guangxi ricegrowing regions. 【Method】The international standard seedling screening method for insect virulence, conventional pest biology observation techniques and spectrophotometry were employed. These methods systematically evaluated the inhibitory effects on the galled seedling rate, pest oviposition, hatching rate, and larval development of rice gall midge after its introduction to pretreated rice at various intervals. Additionally, temporal changes in the total phenolic content of rice secondary metabolites and its correlation with the galled seedling rate were analyzed. 【Result】Both imidacloprid seed dressing(exposed to rice gall midge 5-25 d after treatment) and foliar spray(exposed to rice gall midge 1-20 d after treatment) significantly inhibited rice gall midge infestation(P<0.01, the same below). The silver shoot rate of rice was reduced to 0-3.95% and 0-4.51% respectively. When insects were introduced 13 d after seed dressing, oviposition was significantly reduced(P<0.05, the same below) to 42.33 egg/10 insects. However, the hatch rate reached 69.32%, significantly higher than the water control. When introduced 18-23 d after treatment, both oviposition and hatch rates of rice gall midge showed no significant difference from the control(P>0.05, the same below). For foliar spray, oviposition(21.00 egg/10 insects) was extremely significantly lower than the control when insects were introduced 5 d after treatment, but showed no significant difference compared to control when introduced 10-15 d after treatment. Larval development was markedly inhibited at 13 d after seed dressing and 5 d after foliar spray, the larval body length was 0.43-0.59 mm for seed dressing group, 0.43-0.48 mm for foliar spray group and 0.82-2.47 mm for water control group. By day 22 after insect introduction, larvae in treated groups remained at early instar stages, while the control group had completed pupation, indicating extremely significant differences in developmental progress. Further analysis revealed that both seed dressing and foliar spray application methods induced an increase in total phenol content in rice plants. However, TP levels gradually declined over time, and their dynamic changes showed a significant negative correlation with the incidence of rice silver shoot rate. 【Conclusion】Imidacloprid pretreatment establishes an early insect resistance defense mechanism in rice by inducing the accumulation of total phenols, thereby achieving indirect regulation of rice gall midge population dynamics.更多还原