What is the difference between virulent and non-virulent midge?
Virulent wheat midge are those resistant to the effects of the Sm1 gene. They carry a mutation that allows them to attack wheat plants with the Sm1 gene and survive. A very low level of virulent midge exists within the natural midge population. Non-virulent wheat midge cannot survive the Sm1 gene contained in midge tolerant wheat. If non-virulent midge mate with virulent midge, the progeny of this cross will be non-virulent since this is usually the dominant gene.
