When they're attacked by Russian wheat aphids, leaves of vulnerable barley plants develop tell-tale white streaks and tight, corkscrew curls. These weakened plants produce fewer plump, nutritious kernels needed for feeding cattle or sheep, or for foods such as pearled barley for soups — or malt for making confections or brewing beer.

But an animal-feed barley named Burton, developed by Agricultural Research Service scientists and their university colleagues, resists attack by both kinds, or biotypes, of Russian wheat aphids that are found in this country.

Leaves on Burton plants don't become streaked or curled when the green, one-sixteenth-inch-long aphids puncture them to feed on the plants' sap. Without the snug, rolled-leaf shelters, aphids become more vulnerable to their natural enemies, and more easily knocked off the plant by wind or rain, according to ARS plant geneticist P. Phillip Bregitzer.