Abstract
Stimulative activity of nutrient chemicals including 9 sugars, 22 amino acids, 11 vitamins, 2 sterols, 3 lipids and 6 salts on the feeding was investigated in the Polygonaceae-feeding chrysomelid beetle, Gastrophysa atrocyanea MOTSHULSKY. Four sugars (sucrose, D-glucose, D-fructose and i-inositol), 2 amino acids (L-aspartic acid and L-lysine) and 3 vitamins (niacine, p-aminobenzoic acid and ascorbic acid) were found to enhance the feeding activity. Of these feeding stimulants, D-glucose, D-fructose, L-aspartic acid, L-lysine and ascorbic acid which are present in the host plants seemed to be particularly active in the feeding on host plants of this insect. Feeding response to compounds with acid taste such as L-aspartic acid, niacine, p-aminobenzoic acid and ascorbic acid suggested that the organic acids with identical taste present in polygonaceous plants play a significant role in the host selection of this insect.
