Introductions of greenbug [Schizaphis graminum (Rondani)], Russian wheat aphid [Diuraphis noxia, (Mordvilko)], and sugarcane aphid [Melanaphis sacchari (Zehntner)] into the U.S. has disrupted the production of barley (Hordeum vulgare L.), sorghum [Sorghum bicolor (L.) Moench], wheat (Triticum spp. L.) and other small grain crops and has caused great economic losses. In this review article, information is given about each cereal aphid, its biotypic variation, genetic variability, as well as its management. Although multiple biotypes have been identified for the greenbug, Russian wheat aphid, and sugarcane aphid, a limited number of biotypes are of agronomic importance. For the greenbug and Russian wheat aphid, the aphid biotypes of agronomic importance are highly genetically similar. The sugarcane aphid biotype that has spread on sorghum and Johnsongrass [S. halepense (L.) Pers.] in all sorghum-growing regions is largely one ‘super-clone’. Lessons learned from the past invasions of the greenbug and Russian wheat aphid directly apply to the current sugarcane aphid outbreak. The use of insecticides with multiple modes of action and the use of sorghum hybrids with multiple resistance genes may delay or prevent new sugarcane aphid biotypes from developing. Lastly since the use of classical biological control for management of the greenbug and Russian wheat aphid outbreaks had limited success, classical biological control is not recommended for the management of sugarcane aphids.
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