Our Guest Artist is L. Ciccone, who looked into plant-animal mutualism. Download a coloring book page of this illustration!
Plants have many diverse ways of repelling predators, including developing beneficial partnerships This species, Japanese cherry is commonly used as a decorative tree throughout the eastern United States. In order to defend new leaves from being eaten by other organisms, the Japanese cherry attracts beneficial ants by secreting nectar from glands on the base of its leaves. These glands (called extrafloral nectaries) provide food to ants and in return, the ants kill parasites that threaten the plant’s leaves. Extrafloral nectaries are found in many species of plants, can grow on leaves, stems, or other plant structure, and can be used by organisms other than ants as well. In some plants, the nectar secreted by extrafloral nectaries has also been found to contain antifungal enzymes, which protect the plant against fungal diseases.
I had never noticed extrafloral nectaries on plants before. It was really cool to be able to walk around my neighborhood and to find them on the leaves of this cherry tree! It was interesting to learn about the variety of EFN that exist, as well as speculation as to their functions (such as providing protection from fungi) and development (plants produce more of them when under stress from certain types of herbivory).