Many arthropod pests of agriculture are notorious for migrating among different crops within a large geographic region. Some of these pests also disperse plant pathogens during movement among crops. In the Great Plains of North America, a prominent example involves various cereal aphid species that carry plant pathogens known collectively as yellow dwarf viruses and serve as obligate vectors of these viral pathogens to a variety of grassy crop and non-crop plant hosts. Numerous cereal aphid species, multiple viruses, and a diverse assortment of host plants within the agricultural landscape produce a complex array of interactions that challenge pest management. In this presentation, the aphids, viruses and important plant hosts are identified, and the complexities and implications of various pest-management tactics in wheat and corn are discussed.
