PDF(Pubmed)
Abstract：
In agroecosystems, insects contend with chemical insecticides often encountered at sublethal concentrations. Insects\' exposure to these mild stresses may induce hormetic effects, which has consequences for managing insect pests. In this study, we used an electrical penetration graph (EPG) technique to investigate the feeding behavior and an age-stage, two-sex life table approach to estimate the sublethal effects of thiamethoxam on greenbug, Schizaphis graminum. The LC5 and LC10 of thiamethoxam significantly decreased longevity and fecundity of directly exposed adult aphids (F0). However, the adult longevity, fecundity, and reproductive days (RPd)-indicating the number of days in which the females produce offspring - in the progeny generation (F1) exhibited significant increase when parental aphids (F0) were treated with LC5 of the active ingredient. Subsequently, key demographic parameters such as intrinsic rate of increase (r) and net reproductive rate (R0) significantly increased at LC5 treatment. EPG recordings showed that total durations of non-probing (Np), intercellular stylet pathway (C), and salivary secretion into the sieve element (E1) were significantly increased, while mean duration of probing (Pr) and total duration of phloem sap ingestion and concurrent salivation (E2) were decreased in F0 adults exposed to LC5 and LC10. Interestingly, in the F1 generation, total duration of Np was significantly decreased while total duration of E2 was increased in LC5 treatment. Taken together, our results showed that an LC5 of thiamethoxam induces intergenerational hormetic effects on the demographic parameters and feeding behavior of F1 individuals of S. graminum. These findings have important implications on chemical control against S. graminum and highlight the need for a deeper understanding of the ecological consequences of such exposures within pest management strategies across the agricultural landscapes.
摘要：
在农业生态系统中，昆虫与经常在亚致死浓度下遇到的化学杀虫剂竞争。昆虫暴露在这些温和的压力下可能会引起饥饿效应，这对管理害虫有影响。在这项研究中,我们使用电渗透图（EPG）技术来研究喂养行为和年龄阶段，双性别生命表方法来估计噻虫嗪对绿虫的亚致死作用，Schizaphisgraminum.噻虫嗪的LC5和LC10显着降低了直接暴露的成年蚜虫（F0）的寿命和繁殖力。然而,成年人的长寿，繁殖力，和生殖天数（RPd）-指示雌性产生后代的天数-当用活性成分的LC5处理亲本蚜虫（F0）时，子代（F1）表现出显着增加。随后，在LC5治疗中,主要的人口统计学参数如内在增长率(r)和净繁殖率(R0)显著增加.EPG记录显示，非探测的总持续时间(Np)，细胞间探针通路（C），和唾液分泌到筛元素（E1）显着增加，而暴露于LC5和LC10的F0成年人的平均探查持续时间（Pr）和韧皮部汁液摄入和并发流涎（E2）的总持续时间减少。有趣的是,在F1一代中，在LC5治疗中,Np的总持续时间显著缩短,而E2的总持续时间增加.一起来看,我们的结果表明，噻虫嗪的LC5对S.graminum的F1个体的人口统计学参数和摄食行为具有代际效应。这些发现对针对S.graminum的化学控制具有重要意义，并强调需要更深入地了解农业景观中有害生物管理策略中此类暴露的生态后果。
