Eucalyptus oil vapour treatment provided to Dysdercus koenigii female individuals as virgin adults or during their fifth instar nymphal life led to a fall in the total protein content accompanied by a rise in the free amino acid titre of haemolymph and fat body. However, the level of total lipids in these two tissues under such condition varied in that a decrease and an increase were recorded in haemolymph and fat body respectively. In the ovary of this adult female, the amounts of total proteins and lipids were low, while the value for total free amino acids was high. The implications of all these findings are discussed chiefly in relation to transport, synthesis and degradation of biochemical constituents in the three tested tissues.
