Field poppies do not self-pollinate, a strategy that helps keep the species’ gene pool diverse. Now, researchers at the University of Birmingham in England have successfully transferred two genes from a poppy plant to a self-fertilizing plant called thale cress. The genetically modified thale cress rejects its own pollen and that of close relatives, the researchers report in the journal Science. The experiment may help researchers breed plants that are stronger than their parents and provide better yields.