Global warming can seriously impact on the interaction between prey and predator due to the differences in optimal temperature ranges. Two aphid-ladybug systems, Myzus persicae-Coccinella septempunctata (M-C) and Aphis gossypii-Coccinella septempunctata (A-C) in the pepper were simulated under temperature scenarios with the assumption that the average temperature is higher by 1, 3, 5, and 7°C than that in Seoul in 2000, respectively. The Rosenzweig-Macathur model was corrected to be embedded with hump-shaped temperature-dependent regression models for each system to explore their short-term interaction strength. The long-term interaction strength was quantified by a dynamic index based on the model.
The results showed that the short-term interaction increased and decreased with increasing temperature in both systems and the A-C system had much larger fluctuation patterns easily exceeding the economic threshold density than the M-C system. The dynamic index presented that M-C and A-C had natively strong and weak interaction respectively and they were getting weaker and stronger as temperature increases. It is expected that A-C system would be more sensitive in the short-term and both systems would have the opposite tendency in the long-term under climate change condition.