Cephus cinctus
Symptoms: Damage by sawflies includes premature yellowing of the spike and shriveling of the grain. The larvae girdle the stem (picture at left) and, later in the crop cycle, lodging is common.
- Life Cycle: Sawflies produce one generation per year. The larvae overwinter in the straw (picture at right); in the spring they pupate. Adult sawflies are small, fly-like wasps and appear from late spring to midsummer. The females deposit small white eggs in the upper nodes of stems just below the spikes. Upon hatching, the legless white larvae bore into the stem and tunnel downward, feeding on the pith of the stem. When they have completed their feeding, they descend further and girdle the stem base.
- Hosts/Distribution: Nearly all cultivated cereals and native grasses act as hosts, although wheat is preferred. Fall-sown cereals are more commonly attacked. Wheat lines having solid or partially solid stems are much less susceptible to attack. The wheat stem sawfly is a major problem in the Mediterranean Basin.
- Importance: Sawfly can cause significant damage in some years, but infestations are usually discontinuous.
