Cabbage 
The diseases responsible for most of the cabbage losses are 
clubroot, black ret, blackleg, Fusarium yellows, downy milder, 
root knet, and mosaic. No one disssse causes severe loss of the 
Crope 
Clubrcoot, which is widespread in the Northerr: United States, 
causes enlarged clublike swellings on the root and dwarfs the 
plant. Black rot, which occurs chiefly in humid regions, causes 
large dead spots on the leaves, followed by leef drop and decay 
of the heads. Blackleg is a widespread disease that causes stem 
cankers of seedlings near the soil line and spotting of the leaves, 
Yellows causes a wilting and drop of older leaves and stunting of 
the plants; it mey occur wherever cabbage is grown. Downy mildew, 
which is most prevalent in coastal regions, affects the leaves 
but is chiefly a seedbed disease. Mosaic causes mottling and some 
necrotic spotting of the leaves; it may occur throughout the United 
States. 
Losses from clubroct can be avoided by rotation and use of clean 
seedbed soils. Western-grown seed is usually free from the organ- 
isms causing black rot and blackleg. Hot-water treatment will 
disinfect contaminated seed. Losses from yellows are avoidable by 
the use of resistant varieties. Fungicides will control downy 
mildew in seedbeds and in the field. Mosaic losses cen be reduced 
by isolation of seedbeds from plants that may serve as sources of 
the causal virus. 
Cantaloups 
The losses to cantaloups are caused chiefly by leaf blights, root- 
knot nematodes, and virus diseases. The most important leaf diseases 
are downy mildew, powdery mildew, and anthracnose. Alternaria leaf 
spot also causes some loss. The squash mosaic virus, strains of 
cucumber mosaic virus, and the curly top virus cause serious damage 
in the West. Minor losses are caused by bacterial wilt. 
Losses from many of the diseases affecting cantaloups are regional, 
Downy mildew as a major disesse is confined largely to the Atlantic 
Seaboard and the Gulf States. Anthracnose, alternaria leaf spot, 
and bacterial wilt are important only in humid areas east of the 
Continental Divide. On the other hand, powdery mildew is most 
destructive in California and Arizona, Mosaic viruses are much more 
damaging in Celifornia and Arizona than in the Central and Eastern 
States. Curly top is confined to areas in California and other 
Western States where the insect vector, the beet leaf hopner, occurs. 
The root—-knot nematode causes some damage wherever cantaloups are 
grew. 
The leaf diseases other than powdery mildew are fairly well con- 
trolled by fungicides. Resistant varieties nave greatly reduced 
