High concentrations of trehalose in aphid hemolymph

The major components of hemolymph were examined by 1H-NMR in seven species of aphids, Acyrthosiphon pisum, Aphis gossypii, Aphis sambuci, Lachnus tropicalis, Megoura crassicauda, Myzus persicae and Uroleucon nigrotuberculatum. Trehalose was detected as the main component from these aphids, and its concentrations in these insects were much higher (196 mM in L. tropicalis to 926 mM in A. gossypii) than those of two other homopterous insects, Cryptotympana facialis (91 mM) and Nephotettix cincticeps (53 mM). Concentrations in L. tropicalis and A. gossypii were equivalent to 1.6% to 2.0% of the fresh weight. Glucose appeared to be an artifact in the hemolymph, because it was not found in the hemolymph when validoxylamine A, a trehalase inhibitor, was added.