The discovery of two crop-destroying female Mediterranean fruit flies in the San Fernando Valley may require aerial spraying of the pesticide malathion, agricultural officials said.

The two pests were discovered in traps this week in residential areas of the city's Northridge area, Bob Donley, a deputy director of the county Department of Agriculture and Weights and Measures, said."It is pretty serious," he said. "We feel we have an infestation on our hands" because the two fruit flies were in traps only about three quarters of a mile from each other.