Published online by Cambridge University Press: 10 July 2009
Acclimation had a beneficial effect on Scottish clones of Aulacorthum solani (Kaltenbach) as seen in enhanced reproduction and development at 5°C, compared with non-acclimated clones at this temperature. In contrast, not all Myzus persicae (Sulzer) clones tested benefited. When reared at 5°C for a second generation, both species had slower nymphal development and M. persicae also had less efficient adult reproduction (a longer pre-reproductive period and reduced fecundity) compared with the first generation. Both species demonstrated a high capacity for recovery from low temperatures, A. solani being the better of the two. In general however, the ability of clones to survive, reproduce and develop at low temperatures or upon transfer to high temperatures, was variable and was not related to annual cycle, origin or organophosphorus resistance. These differing responses support previous results and are suggested as being an efficient means of ensuring variability in aphid populations surviving after winter.