Sugar feeding disrupts ant-aphid mutualism to control rosy apple aphid

Rosy apple aphid (Dysaphis plantinoides) and ant (Lasius niger) mutualism is disrupted by sugar dispensers, reducing aphid colony formation and shoot damage. At 1231 dispensers/ha (1-in-2), infestation dropped significantly; lower densities (1-in-4, 1-in-10) showed lesser but measurable effects. Field study in Nieuwerkerk (NL) used 2462 trees/ha from 21 April 2021 to 19 April 2023. Results show reduced ant tending, increased predation, and lower infestation at higher dispenser densities. Practical application balances cost, labour, and ecological impacts. Data and mechanisms illustrated in figures. References key studies on ant-aphid mutualism and biocontrol. Contact: delphy.nl.