Plum pox show no symptoms on leaves or fruit. Not all infection in "Prunus" are characterized by a ring symptom on leaves. Several cultivars show yellowing line patterns and blotches, or necrotic ring symptoms on expanded leaves. Leaf distortion has also been observed. Infected fruit can develop yellow rings or blotches, or brown rings, and some plum and apricot fruit can be severely deformed and bumpy. The seed of many infected apricots and some plums show rings. Many non-"Prunus" species, in at least nine plant families, have been infected artificially with one or more strains of the plum pox virus, and in
Plum cake to World War I, cakes, including plum cakes, were baked along with loaves of bread. "A smaller cake or pasty might be slipped in or pulled out after the baking had begun, but a raised pie with well-protected sides, or a large plum cake, would take at least the same time as the loaves, and experienced housewives made them in sizes to do so." The English variety of plum cake also exists on the European mainland, although "plum cake" there more usually refers to baked cakes made with fresh, rather than dried fruit. In French cooking, plums are an ingredients