Infected areas on fruit turn brown and appear rusty. Symptoms usually occur on green fruit and disappear as the fruit develops. This disease occurs frequently when roses are nearby. This disease is caused by a soil-inhabiting bacterium, Agrobacterium tumefaciens , which infects many ornamentals in the home garden. The symptoms are rough, rounded galls or swellings that occur at or just below the soil surface on stems or roots.
Young galls are light green or nearly white in color.
As they age, the galls become darkened and woody and range in size from small swellings to several inches across. The galls disrupt the flow of water and nutrients traveling up from the roots and stems, thus weakening and stunting the top of the plant. Occasionally, the disease becomes systemic and the galls are seen above the ground. For new plantings select disease-free plants that have no evidence of galls. Remove infected plants as soon as galls are observed.