Compared with single insecticides, insecticide mixtures can enhance efficacy, broaden the spectrum of activity, and potentially delay resistance evolution in Aphis gossypii. However, their sublethal and intergenerational effects remain poorly understood. Here, the life table analysis was used to evaluate the effects of mixture treatments prepared from sublethal (LC20) and low-lethal (LC50) doses of nitenpyram, pymetrozine, and beta-cypermethrin on the directly exposed F0 generation of A. gossypii and its effects on the F1 progeny. Total protein, free amino acid, and vitellogenin (Vg) contents were measured, and the sequence and expression of Vg and vitellogenin receptor (VgR) genes were analyzed. Exposure to the mixture treatments significantly reduced longevity and fecundity in both generations while increasing total protein and free amino acid contents. Domain prediction confirmed the conserved structural features of AgVg and AgVgR, and phylogenetic analysis showed that both clustered with homologs from closely related aphid species. RT-qPCR further revealed that the mixture treatments significantly suppressed AgVg and AgVgR expression. In conclusion, exposure to the mixture treatments affects both directly exposed individuals and their progeny, providing a basis for evaluating the ecological consequences of insecticide mixtures and optimizing their use within integrated pest management strategies for A. gossypii.
The new aphid species Aphis tanaceticola sp. nov., living on Tanacetum parthenium (L.) Sch.Bip. in Ankara Province, Türkiye, and on Tanacetum sp. (Asteraceae: Anthemideae) in Mazandaran Province, Iran, is described and illustrated based on the fundatrix, normal and alatiform apterous and alate viviparous females, and intraspecific variations between short-haired Iranian and long-haired Turkish populations are discussed. Differential diagnoses to morphologically similar species and to the Anthemideae-feeding Aphis spp. are given. An identification key for Anthemideae-feeding Aphis spp. with sclerotic abdominal dorsum anterior to siphunculi is provided.
Predators play a key role in regulating herbivore populations in agroecosystems, and preserving natural and semi-natural habitats within agricultural landscapes can help maintain viable natural enemy populations. In this study, we used artificial caterpillars to assess how habitat–stratum combination and season are associated with attack rates as a proxy for predation pressure in tea plantations in Fujian Province, China. We compared three habitat–stratum combinations: tea canopy (TC), tea ground (TG), and adjacent forest ground (FG). Overall, 33.7% of the artificial caterpillars showed signs of predation, with attack rates of 27.9% by arthropods and 5.8% by vertebrates. Attack rates were significantly influenced by both habitat–stratum combination and season. Specifically, ground habitats (TG and FG) exhibited the highest attack rates, although no significant difference was detected between TG and FG. Total and arthropod attack rates peaked in summer and autumn, whereas vertebrate attack rates remained consistent across seasons. These findings indicate that attack rates on artificial prey in tea agroecosystems varied strongly with habitat–stratum combination and season, with arthropods as the dominant predator guild. Maintaining habitat heterogeneity and adopting stratum-specific field management practices (e.g., retaining litter layers for ground-dwelling predators and minimizing soil disturbance) represent plausible strategies, though their effects on realized pest suppression and crop yield remain to be experimentally tested.
Physaria thamnophila (Zapata bladderpod) is a federally endangered plant restricted to southernmost Texas and northeastern Mexico. We conducted a seasonal inventory of arthropods in occupied habitat at the Arroyo Ramirez Tract of the Lower Rio Grande Valley National Wildlife Refuge. Arthropods were sampled from 40 plots during summer and fall 2024 and winter and spring 2025 using sticky cards, pitfall traps, and vacuum collections. Specimens were classified into higher-level taxa, primarily orders, with Coleoptera, Hymenoptera, and Lepidoptera additionally identified to family. Seasonal differences in abundance, taxonomic richness, and diversity were evaluated using repeated-measures mixed models, supplemented by plot-level cluster bootstrapping. We collected 23,721 arthropods representing 20 higher-level taxa. Total abundance was significantly higher in spring (8098 specimens) and winter (6925) than in summer (4952) and fall (3746). Hymenoptera, Diptera, Coleoptera, and Thysanoptera accounted for 86.6% of specimens. Order-level richness peaked in spring (9.23 orders per plot), whereas Shannon diversity was significantly lower in winter (1.23) than in other seasons. Coleoptera abundance peaked in winter, predominantly among Buprestidae, although beetle family richness and diversity peaked in spring. These findings demonstrate seasonal variation in arthropod abundance, composition, richness, and diversity, providing a baseline for future studies of plant–arthropod interactions and P. thamnophila conservation.
Insect growth regulators (IGRs), including chitin synthesis inhibitors (CSIs), juvenile hormone analogues (JHAs), and ecdysteroid agonists, have become important components of sustainable pest management because they can selectively disrupt insect-specific developmental, endocrine, or structural processes that differ from those in vertebrates. Rather than treating all IGR classes as operating through one common pathway, this review proposes an integrative framework in which class-specific primary modes of action interact with endocrine regulation, metabolism, stress responses, and ecological context. Across the literature, IGR exposure is associated with changes in carbohydrate, lipid, and protein metabolism, altered detoxification and digestive enzyme activities, and changes in reproductive physiology that can reduce insect fitness. However, these metabolic responses vary substantially with compound class, species, developmental stage, dose, and exposure duration. Their occurrence does not by itself establish active resource reallocation, a common metabolic crisis, or a causal role in mortality. Endocrine–metabolic crosstalk is therefore considered here as a mechanistic framework and testable hypothesis rather than an established universal mechanism of IGR toxicity or resistance evolution. Field-evolved resistance to IGRs is mechanistically diverse and can involve target-site changes, altered detoxification, reduced penetration, transport processes, and regulatory mechanisms, with the strength of evidence varying among compounds and pest species from functionally supported mechanisms to candidate pathways. The review also evaluates integration of IGRs with conventional insecticides and biological control agents and examines how climate warming may alter pest phenology, developmental timing, and temperature-dependent IGR performance, while acknowledging that direct empirical evidence linking climate warming specifically to IGR endocrine or metabolic sensitivity remains limited. Future progress will require stronger functional validation of proposed endocrine–metabolic links, climate-informed deployment strategies, and resistance management based on validated mechanisms and multiple control tactics.
