Studies on the haemocytes of Aphis gossypii Glover (Aphididae: Homoptera)
Abstract
Five types of haemocytes were found in the haemolymph of Aphis gossypii Glover, viz., prohaemocytes (PRs), plasmatocytes (PLs), spindle shaped haemocytes (SHs), granulocytes (GRs) and adipohaemocytes (ADs). The first instar nymph contained only PRs. Second and third instar nymph had 81 to 69% PRs and 19 to 31% PLs. Fourth instar nymph contained 66% PRs, 30% PLs and 4% GRs. The adults (both apterous and alatae) had 62–64% PRs, 20–22% PLs, 8–10% GRs and 6–8% ADs. The blood circulation studies in the wings of A. Gossypii showed the outward flow of blood from the body through approximately the anterior half of each wing and returned through the posterior half. The blood flow was vigorous and fairly constant in young adults but declined and found more variable with increase of age. PRs and PLs were observed with nonuniform distribution in the haemolymph of wing veins.
