Among the main biotic stresses of carrot crops, the pests such as nematodes and carrot fly and diseases including cavity spot, crown or cottony rot, black rot or leaf blight are targets for scientific researches over the world. Components of integrated control programs for all these organisms are under development. Success of such programs requires systemic approaches including knowledge about genetic diversity of the targets, their epidemiology, host physiology and host resistance mechanisms and compatibility among the different control tools or between programs targeting different goals.