No longer unbothered: Demographic shifts and long-term effects in the phloem feeders after urban particulate matter exposure

Abstract Insect herbivory and plant-pollutant interactions are inseparable processes in terrestrial ecosystems. Aphid phloem feeders are highly tolerant insect herbivores, thriving even in contaminated environments, including motorway edges. However, the influence of contemporary levels of particulate matter (PM)—a pollutant exerting both mechanical and chemical influence on invertebrates—remain unexplored in this group. The effects of foliage-accumulated PM on the life history of the model species, the linden aphid Eucallipterus tiliae, which commonly occurs in urban tree canopies, were investigated. Aphids were reared individually on Tilia cordata leaves treated with increasing PM concentrations (levels I-III, and the clean control) reflecting real-world pollution deposition. Randomly selected, healthy larvae born by females from different pollution levels were transferred to uncontaminated conditions and used to assess F1 survival. No significant changes were observed in larval development time or instar survival across pollution levels, confirming the aphid’s general tolerance. However, total fecundity and reproductive period duration declined with increased pollution. The observed shifts in demographic parameters were not strictly linear. Despite lowered net reproductive rate under pollution, the intrinsic and finite rates of increase were the highest at pollution level III, indicative of reproductive acceleration. The survival of F1 originated from females cultured under pollution level III declined significantly despite rearing in pollution-free conditions, and malformed larvae were born from females kept in pollution levels II and III, providing the first evidence of PM-induced transgenerational effects. The results advance our understanding of long-term effects of PM exposure in herbivorous invertebrates.