Salivary symbionts in the potato leafhopper, Empoasca fabae

The potato leafhopper, Empoasca fabae, feeds on a wide range of agricultural crops, including potato, alfalfa and soybean. The saliva of the potato leafhopper has previously been shown to play a role in hopperburn, a disease characterized by the yellowing and eventual necrosis of susceptible plant leaves. In an attempt to understand the components of the leafhopper’s saliva, we isolated leafhopper salivary glands and screened them for symbiotic bacteria. Diagnostic polymerase chain reaction showed the presence of Baumannia cicadellinicola, a species of symbiotic bacteria reported near the midgut of other leafhopper species, in the salivary glands of the potato leafhopper. Insect-bacteria symbioses are common in the Hemiptera, where the bacteria often provide novel compounds to their insect host. The discovery of salivary symbionts in the potato leafhopper could lead to a better understanding of compounds present in the leafhopper’s saliva and how these components interact with a plant to produce the symptoms of hopperburn.