Sooty Mold of Pear
Sooty mold fungi of the genus Capnodium cause an unsightly blackening over the surface of fruit and leaves. Sooty mold attacks many plants and is most common on pear, although it can affect all tree fruits and tree nuts. The fungi live on honeydew excreted by insects such as aphids, psylla, and whiteflies. When only a few insects are present on host plants excreting only a small amount of honeydew, sooty mold appears in spots. When insect secretions are abundant, the surfaces of leaves and fruit might have a near-continuous coating of the black, tissue-paper-thin, sooty mold.
Control is directed against the insects producing the honeydew. These insects need to be identified before appropriate controls can be undertaken.