Rutin: a phagostimulant for the polyphagous acridid Schistocerca americana

Rutin was demonstrated to be a phagostimulant for the grasshopper Schistocerca americana across a very wide concentration range. The effect was not maintained over a period of days if the insects had already ingested a large amount, but when individuals were given different concentrations on disks as supplements to their lettuce diet, they tended to self select a moderate quantity on a daily basis. In long term experiments on food utilization and growth rates using artificial diet, no beneficial effects of rutin could be demonstrated. Ingested rutin was absorbed and some of it deposited in the cuticle. Most was excreted as the aglycone quercetin. The possible functional significance of the phagostimulatory effect is discussed.Dedicated to G.B. Marini-Bettolo