Abstract.The eggs of the southern green stink bug,Nezara viridula(L.) (Hemiptera: Pentatomidae), are successfully attacked byTrissolcus basalis(Woll.) (Hymenoptera: Scelionidae) and are recognized as hosts by a secretion applied to the egg chorion. This secretion is produced by the follicular cells in the proximal region of the ovariole of the female pentatomid and functions as an adhesive for attaching the eggs to the oviposition substrate. The adhesive and kairomone activity could be partially removed with water. This water extract elicited host recognition behaviour inT. basaliswhen applied to glass beads which stuck together as the extract dried. The adhesive and kairomonal activity was removed completely with acetone since acetone‐washed host eggs were not recognized byT. basalis.Application of the acetone extract to glass beads stimulated ovipositional probes byT. basalis.The adhesive appeared to be composed of a mucopolysaccharide–protein comp