Eggs are laid singly on ears at the pre-flowering stage. If eggs are laid later, larvae are incapable of developing normally. Mainly parasites , diapause and phenological factors determine the life of this species. Heavy rainfall during the flight period can cause individuals to fall to the ground and die. D amage Average infestation on wheat of 15 larvae per ear can lead to yield reductions.
Partial attacks distort ears, which become soft to the touch and seem abnormally thin.
Ears of rye may exhibit mines . The envelope of the grain often ruptures and a secondary fungal infection develops. Grain value, the germination power, the speed of germination, the vigour and the weight of grains can be considerably reduced. The baking quality of rye is poor. Female and wheat at the favourable stage for egg-laying Female laying eggs on flowering ears of wheat. .