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Aphid Control in Small Grains

Joanne Whalen (February, 2006)

Summary

The most common aphid species found in Delaware small grain fields are the English grain aphid, oak-bird cherry aphid, corn leaf aphid and the greenbug. Infested plants appear stunted and discolored. A lack of moisture in midwinter and a cool spring result in more significant damage. The most significant damage occurs when large numbers of aphids feed on the grain head causing shriveled or blasted heads. All four species can also transmit barley yellow dwarf mosaic, a serious yield limiting virus. Aphid outbreaks are favored by a mild winter followed by a cool, dry spring. Under these conditions, aphids reproduce rapidly whereas their natural enemies reproduce slowly.