Aphids excrete a sugary substance called honeydew, which can coat leaves and stems, attracting ants and promoting the growth of sooty mould.
Aphid feeding can distort new growth, causing leaves to curl, yellow, or become stunted.
Aphids suck sap from plants, depriving them of essential nutrients. This results in chlorosis, where leaves turn yellow and may become curled or stunted.
This black, powdery fungus grows on the honeydew left by aphids, further damaging the plant.