Local and systemic interactions of Aulacorthum solani and Myzus persicae on tomato

Herbivorous insects frequently share host plants and require similar abiotic conditions. Therefore, they often occur simultaneously in crops. Tomato plants express intrinsic and induced defence mechanisms against a variety of herbivorous insects like aphids. Factors associated with the aphids' sucking activity can affect subsequent herbivores directly or indirectly through different defence reactions in the plant. The plant response to preliminary herbivory can be negative as well as beneficial for subsequent attackers. The present study was aimed to investigate intra- and interspecific interactions between the two aphid species Aulacorthum solani Kaltenbach and Myzus persicae Sulzer (both Hemiptera: Aphididae) on a local and systemic level regarding subsequent aphid infestations on tomato (Solarium lycopersicum L. (Solanaceae)). Intraspecific but no interspecific effects were observed. Both aphid species responded to a previous infestation of conspecific aphids with reduced reproduction when feeding on an adjacent (systemic) leaf. However, no significant effects were observed locally on the same pre-infested leaf, except that A. solani showed an accelerated development on these leaves. Our study reveals specific interactions of the two aphid species A. solani and M. persicae on tomato and indicates different associated defence reactions of the plant. The aphid performance reactions on previous infestation events as well as possible plant mechanisms and advantages for the plant are discussed.