Bulletin 208, Cucumber Diseases in Florida


 dence is available to show that it survives in the soil from one
 season to the next.

 BACTERIAL WILT
 This wilt disease of cucumbers is caused by a bacterial organ-
 ism, Bacillus tracheiphilus E. F. S. The disease is very common
 and destructive in the northern cucumber districts but in the
 south it is of less importance. In Florida, only isolated cases
 have been observed and in these instances the economic impor-















 Fig. 23. Cucumbers affected with bacterial wilt.

 tance of the disease was negligible. It has been known in Florida
 for probably 15 years. During the last two seasons it has been
 occasionally observed in the field in commercial plantings. The
 probable reason for the scarcity of the disease may be the limited
 areas infested by the striped cucumber beetle, Diabrotica vittata
 Fab. This insect has been found in two small isolated sections of
 the state. In northern sections this insect has been found to be
 most important in the spread of the disease. It has also been
 demonstrated2 that the organism is not carried on the seed. The
 conditions in Florida are such that the organism might survive
 on wild host plants during the period when cucumbers are not
 grown. This has not been thoroughly investigated, nevertheless
There may be possibilities of the survival of the organism in this
way.
 Description: The first symptom of bacterial wilt is a gradual
 progressive wilting of the plant, the earliest evidences of which
 2Rand, F. V. & Enlows, E. M. A. Bacterial Wilt of Cucurbits. U. S. D. A.
 Bul. 828:21, 1920.