Abstract:

【Objective】 The continuous cropping system in mixed single- and double-season rice areas provides an uninterrupted food supply for the overwintering and subsequent 2-3 generations of Chilo suppressalis (Walker), leading to increased pest populations and more severe crop damage. This study aimed to evaluate the control efficacy of an intelligent active aerosol dispenser for mating disruption against C. suppressalis in early and late rice. 【Method】 A mating disruption plot and a farmer-managed control plot were established in a mixed single- and double-season rice area in Sanjie Town, Shengzhou, Zhejiang Province. On April 12, 2024 (eight days before rice transplanting), intelligent active aerosol dispensers were deployed in the mating disruption area. High doses of sex pheromone were released continuously during both early and late rice seasons to disrupt the mating behavior of C. suppressalis. Field surveys were conducted to monitor moth catches in pheromone traps, the percentage of damaged plants, and larval density. Natural enemies were sampled using malaise traps and suction samplers during the early and late rice seasons, respectively. 【Result】 The mating disruption efficacy on C. suppressalis adults was 94.1% ± 0.02% for the overwintering generation, 78.6% ± 12.7% for the first generation, and 87.3% ± 0.01% for the second generation. The disrupted rates for non-target pests were 85.6% ± 0.07% for Sesamia inferens (Walker) in early rice and 79.2% ± 0.07% for Cnaphalocrocis medinalis Guenée in late rice. During the early rice season, the technology reduced larval density of C. suppressalis by 71.5%-83.3% and the percentage of damaged plants by 59.4%-74.5%. Although natural enemy abundance did not differ significantly, the beneficial-to-pest ratio was markedly higher in the mating disruption plot (2470.6% ± 594.5%) than in the control plot (148.8% ± 38.4%). In the late rice season, larval density and plant damage of C. suppressalis were reduced by 80.7%-90.9% and 61.2%-89.6%, respectively, while the leaf rolling rate caused by C. medinalis decreased by 63.7%. Again, natural enemy populations showed no significant difference, but the beneficial-to-pest ratio was higher in the mating disruption area (333.3% ± 91.3%) than in the control (64.2% ± 24.9%).【Conclusion】 The intelligent active aerosol dispenser effectively suppressed the larval population of C. suppressalis and reduced crop damage in the mixed cropping rice area. It also demonstrated significant control effects against S. inferens and C. medinalis. Furthermore, the technology had no adverse impact on natural enemy populations and resulted in a higher beneficial-to-pest ratio compared to conventional farmer practice.

Key words: Chilo suppressalis (Walker), Sesamia inferens (Walker), Cnaphalocrocis medinalis Guenée, sex pheromone dispenser, mating disruption rate, double-season rice, cropping system, ratio of beneficial insects to pests

摘要：

【目的】单双季水稻混栽区的耕作制度为二化螟越冬代和后续的2~3个世代提供了不间断的食料条件，导致虫量增加，危害加重。本研究评价了智能主动喷射型交配干扰释放器对早晚两季水稻二化螟的防控效果。【方法】在浙江嵊州三界镇的单双季混栽稻区，设置交配干扰区和农户自防对照区，在2024年4月12日，即水稻移栽8 d前，在交配干扰区设置主动释放的智能喷射型性信息素释放器，在早稻和晚稻期间连续不间断地喷射高剂量的性信息素干扰二化螟的求偶。同时，调查监测诱捕器中的诱蛾量、水稻被害植株数量和二化螟各龄幼虫数量，早稻、晚稻期间分别采用马氏网、吸虫器调查田间天敌种群量。【结果】越冬代二化螟成虫的交配干扰抑制率为94.1%±0.02%，一代成虫抑制率为78.6%±12.7%，二代成虫抑制率为87.3%±0.01%。同时，对早稻大螟成虫的抑制率为85.6%±0.07%，晚稻稻纵卷叶螟成虫的抑制率为79.2%±0.07%。早稻期间，交配干扰区二化螟幼虫数量减少了71.5%~83.3%，水稻植株被害率下降了59.4%~74.5%。自然天敌的种群数量差异不显著，但对照区益害比为148.8%±38.4%，交配干扰区益害比为2470.6%±594.5%。晚稻期间，交配干扰区二化螟幼虫数量减少了80.7%~90.9%，水稻植株被害率减少了61.2%~89.6%，稻纵卷叶螟卷叶率降低了63.7%。自然天敌数量没有差异，但益害比对照区为64.2%±24.9%，交配干扰区为333.3%±91.3%。【结论】主动释放的智能喷射型性信息素交配干扰技术有效控制了单双季稻区二化螟幼虫的数量，减轻了其危害，对大螟和稻纵卷叶螟也有显著的防治作用， 同时，对稻田自然天敌种群没有负面的影响，其益害比反而更高。

关键词: 二化螟, 大螟, 稻纵卷叶螟, 性信息素释放器, 交配干扰抑制率, 双季稻, 耕作制度, 益害比