The seeds of parasitic plants of the genera Striga and Orobanche will only germinate after induction by a chemical signal exuded from the roots of their host. Many of these compounds have been isolated and identified from a number of different plant species and are collectively called the strigolactones. Here we show that the strigolactone germination stimulants are derived from the carotenoid pathway. This finding is used to create crop species that do not induce germination of parasitic plant seeds anymore and therefore are resistant to parasitic plants. Also provided is a method to use chemicals and mycorrhizae to inhibit germination stimulant production to control parasitic plants. Also provided are strigolactone overproducing trap and catch crops.