Symbiotic associations between microbes and insects are widespread, and it is frequent that several symbionts share the same host individual. Hence, interactions can occur between these symbionts, influencing their re...Symbiotic associations between microbes and insects are widespread, and it is frequent that several symbionts share the same host individual. Hence, interactions can occur between these symbionts, influencing their respective abundance within the host with consequences on its phenotype. Here, we investigate the effects of multiple infections in the pea aphid, Acyrthosiphon pisurn, which is the host of an obligatory and several facultative symbionts. In particular, we study the influence of a coinfection with 2 protective symbionts： Harniltonella defensa, which confers protection against parasitoids, and Rickettsiella viridis, which provides protection against fungal pathogens and predators. The effects of Hamiltonella-Rickettsiella coinfection on the respective abundance of the symbionts, host fitness and efficacy of enemy protection were studied. Asymmetrical interactions between the 2 protective symbionts have been found： when they coinfect the same aphid individuals, the Rickettsiella infection affected Hamiltonella abundance within hosts but not the Hamiltonella-mediated protective phenotype while the Hamiltonella infection negatively influences the Rickettsiella-mediated protective phenotype but not its abundance. Harboring the 2 protective symbionts also reduced the survival and fecundity of host individuals. Overall, this work highlights the effects of multiple infections on symbiont abundances and host traits that are likely to impact the maintenance of the symbiotic associations in natural habitats.展开更多
Ecological interactions are of paramount importance for the functioning and health of ecosystems. Phytophagous insects are part of complex ecological networks involving abiotic factors, host plants, natural enemies, a...Ecological interactions are of paramount importance for the functioning and health of ecosystems. Phytophagous insects are part of complex ecological networks involving abiotic factors, host plants, natural enemies, and benefi- cial organisms （McLean et al., 2016）. Insects and plants are also associated durably or transitorily with a wealth of microbes including pathogens, commensals and beneficial partners from a vast array of microbial taxa （Sugio et al., 2015）. In recent years, evidence has accumulated that microbes directly or indirectly influence plant-insect interactions at individual, population and community levels.展开更多
文摘Symbiotic associations between microbes and insects are widespread, and it is frequent that several symbionts share the same host individual. Hence, interactions can occur between these symbionts, influencing their respective abundance within the host with consequences on its phenotype. Here, we investigate the effects of multiple infections in the pea aphid, Acyrthosiphon pisurn, which is the host of an obligatory and several facultative symbionts. In particular, we study the influence of a coinfection with 2 protective symbionts： Harniltonella defensa, which confers protection against parasitoids, and Rickettsiella viridis, which provides protection against fungal pathogens and predators. The effects of Hamiltonella-Rickettsiella coinfection on the respective abundance of the symbionts, host fitness and efficacy of enemy protection were studied. Asymmetrical interactions between the 2 protective symbionts have been found： when they coinfect the same aphid individuals, the Rickettsiella infection affected Hamiltonella abundance within hosts but not the Hamiltonella-mediated protective phenotype while the Hamiltonella infection negatively influences the Rickettsiella-mediated protective phenotype but not its abundance. Harboring the 2 protective symbionts also reduced the survival and fecundity of host individuals. Overall, this work highlights the effects of multiple infections on symbiont abundances and host traits that are likely to impact the maintenance of the symbiotic associations in natural habitats.
文摘Ecological interactions are of paramount importance for the functioning and health of ecosystems. Phytophagous insects are part of complex ecological networks involving abiotic factors, host plants, natural enemies, and benefi- cial organisms （McLean et al., 2016）. Insects and plants are also associated durably or transitorily with a wealth of microbes including pathogens, commensals and beneficial partners from a vast array of microbial taxa （Sugio et al., 2015）. In recent years, evidence has accumulated that microbes directly or indirectly influence plant-insect interactions at individual, population and community levels.
