sistant to early and late blight has been introduced and Fusarium 
yellows-resistant varieties are available. In Florida flooding of 
celery soils and heavy applications of cyanamide have helped to 
reduce loss from pink rot, but the disease is hard to control. 
Destruction of perennial weed hosts near celery fields helps to 
reduce damage by mosaic viruses. Western aster yellows has not 
bean controlled satisfactorily. 
Corn, Sweet 
The sweet corn crop may be damaged by seedling blights; ear, 
stalk, and root rots; smut; leaf blight; and bacterial wilt. The 
stubby root nematode also causes some injury. 
Seedling blights occur in all corn-growing areas, but their 
severity depends on the climate. Stalk, ear, and root-rots cause 
variable losses in both northern and southern areas. Smut and 
leaf blight are present in all corn-growing areas; the latter has 
been particularly severe in Florida. Bacterial wilt occurs through- 
out the Corn Belt and in the Eastern and Southern States. Nematode 
injury is more common in the South. 
Seed decay can be reduced by chemical seed treatment. In recent 
years there has been some spraying for control of leaf blight in 
Florida. Resistant varieties have reduced losses from bacterial 
wilt. Good cultural practices help to control stalk and ear rots 
and smut, 
Cucumbers, Greenhouse 
The principal causes of losses of cucumbers in the greenhouse are 
powdery mildew, cucumber mosaic, and root knot. There are minor 
losses occasionally from bacterial wilt and from stem rot. All 
these diseases may occur wherever the crop is grom. 
Powdery mildew can be controlled by proper temperature and venti- 
lation and by sulfur dusts, Fumigation to destroy aphid vectors 
helps to avoid serious loss from cucumber mosaic and bacterial wilt. 
Steam sterilization of the soil will generally prevent damage from 
root-knot nematodes and from stem rot. 
Cucumbers for Fresh Market 
The losses of cucumbers grown for fresh market are caused chiefly 
by downy mildew, anthracnose leaf blight and fruit rot, angular 
leaf spot, cucumber mosaic virus, and root-knot nematodes. Minor 
losses are caused by scab and bacterial wilt. 
Loss from downy mildew is probably greatest, although it is con- 
fined to the Atlantic coast. Anthracnose and angular leaf spot 
are widespread in humid regions east of the Continental Divide, and 
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