Plant-mediated effects of beneficial soil microbes on natural enemies
Abstract: Plants have evolved sophisticated mechanisms to defend themselves against
herbivory. One such mechanism is the release of volatiles by infested plants which inform
natural enemies about the presence of prey, eventually resulting in pest suppression. Plantpredator interactions can be affected by beneficial microbes living belowground as they are known to enhance the resistance of plants against pests. Nevertheless, the plant-mediated effects of soil microbes on the performance of natural enemies have not been widely studied. Here we studied whether beneficial soil microbes affect the biology and behavior of aboveground predators and parasitoids. We recorded the survival, offspring production, prey
consumption/parasitism, as well as the behavioral responses of two mirids, a phytoseiid
predator and a parasitoid as affected by the inoculation of tomato plants with beneficial
microbes. Our results highlight the variable effects of microbes on natural enemies depending
on the microbe, the herbivore and the natural enemy species studied.