Conspecific and heterospecific interactions between two omnivorous predators on tomato

► We tested interactions on Nesidiocoris tenuis and Macrolophus pygmaeus. ► Conspecific and heterospecific interactions reduced predator progeny. ► IGP between predators is related to predator density and prey availability. ► Coexistence of omnivorous predators can increase predator plant feeding. ► IGP between predators may explain failure in biological control programs.