Studies On the Feeding and Nutrition ofTuberolachnus Salignus(Gmelin) (Homoptera, Aphididae)

ABSTRACT Several workers have tried to ascertain the nitrogenous and carbohydrate materials which are ingested by aphids and coccids by analysing juices, phloem exudates and extracts obtained from the insects’ host plants (Evans, 1938; Michel, 1942; Lindemann, 1948; Auclair & Maltais, 1950, 1952; Gray, 1952; Hackman & Trikojus, 1952; Gray & Fraenkel, 1954; Bacon & Dickinson, 1957). It remains to be established, however, whether the insects ingest materials in the same form and at the same concentration as they occur in their host plants. The present paper gives details of a method, outlined by Kennedy & Mittler (1953), for obtaining the sap which normally enters the alimentary canal of feeding Tuberolachnus salignus (Gmelin). By determining the nitrogen and sugar composition of this sap and that of the honeydew excreted by the aphid, it was possible to examine the chemical relationship existing between the insect’s food and its excreta.