Research

Publications
Title: Neonicotinoid insecticide causes multigenerational impairment of inducible antipredator defenses in Daphnia
First author: Sha, Yongcui; Zhang, Huan; Wang, Haiqing; Hansson, Lars-Anders; Niu, Cuijuan
Journal: ENVIRONMENTAL RESEARCH
Years: 2025
Volume / issue: /
DOI: 10.1016/j.envres.2025.121076
Abstract: Nowadays organisms encounter not only natural challenges from predators but also significant anthropogenic stressors, such as insecticides, which can profoundly disrupt their normal growth and behavior. However, the knowledge on their potential interactions remains largely unknown, particularly regarding how insecticides may affect predator-prey interactions and prey responses across multiple generations. Here, we conducted a multi- generational experiment exposing two generations of Daphnia sinensis to predator kairomone from fish (Carassius auratus) and imidacloprid (a widely used neonicotinoid insecticide), both individually and in combination, followed by rearing two generations in a clean medium to examine effects on a series of traits including morphology, behavior, physiology, growth rate and reproduction. We found that fish kairomone and imidacloprid affected D. sinensis in different ways across generations, with effects remaining detectable even two generations after removing the threats. Combined stressors induced more pronounced adverse long-term effects than single stressors, affecting traits such as body size, thoracic limb movement, age at first reproduction and offspring number. Exposure to imidacloprid over generations led to a cumulative weakening of essential anti- predator defenses, especially in the development of tail spine and reproductive traits, with more pronounced effects observed in the second exposure generation. Our findings highlight the complex interplay between natural and anthropogenic stressors and underscore the importance of considering multigenerational responses to fully understand their ecological impacts on aquatic ecosystems. Further research is essential to explore the underlying mechanisms driving these effects and to inform strategies for mitigating the ecological risks posed by continuous insecticide exposure.