Flea beetles (species of the genus Phyllotretra) are serious pests of cruciferous crops, causing millions of dollars losses each year, despite the use of chemical pesticides. Our current pesticides are broad-spectrum in their activity, killing not just the pests, but also many non-target species, including beneficial insects such as pollinators and predators. Here, an alternative set of pesticides, based on double- stranded RNA (dsRNA), is shown to be effective at killing flea beetles when the dsRNAs are applied to a leaf surface and fed to the insects. Insects that fed on leaves sprayed with the dsRNAs died within 8 days of first exposure, but also showed reduced feeding activity within several days, thereby reducing feeding damage to the plants. Importantly, the dsRNAs were designed to be specific for the flea beetles, and when delivered to non-target beetles, no adverse effects were observed, illustrating the specificity of this new type of pesticide.
展开▼