Salivary proteins of Lygus hesperus (Hemiptera: Miridae)

Lygus hesperus (Hemiptera: Miridae) is a key agricultural pest in the western United States. Lygus feeding causes abscission of floral buds and deformation of fruit on a wide range of fruit, vegetable, and field crops. Lygus feeding involves the injection of saliva which causes the enzymatic degradation of host plant tissues. We used Orbitrap Mass Spectrophotometry to identify salivary proteins injected into liquid diet by adult L. hesperus. Saliva collection plates constructed from sterile petri dishes contained a solution of 5% sucrose which was covered with stretched parafilm. Collection plates were exposed for 24 h to ≈2000 prereproductive adults, which stylet-probed and injected salivary proteins into the sucrose solution. Concentrated salivary proteins were trypsin digested before analysis by Orbitrap mass spectrophotometry. The resulting peptide masses were analyzed for protein identification against the NCBI nonredundant protein database. This study documents salivary proteins of L. hesperus and will facilitate further study of Lygus salivary constituents and their role in Lygus/host interactions.