Club-Root of Cabbage and Related Crops
Vegetable Disease Information Note 17 (VDIN-0017)
Charles W Averre, Extension Plant Pathologist
of cabbage and related crops is a serious disease in North Carolina because
infested fields remain unsuited for production of cabbage and related
crops for many years, and the fungus has a history of spreading to other
fields in the community. This disease is probably the major reason for
the decline of commercial cabbage production in some northwestern counties
in North Carolina. It has also caused damage in gardens in other areas
of the state, primarily in home gardens. Every effort should be made to
avoid the introduction of the fungus in contaminated lots of transplants.
is restricted to plants in the mustard family, both cultivated and weeds,
and to a few other plants: corn poppy (Papaver rhoeas), mignonette
(Roseda odorata), ryegrass (Lilium perenne), and red clover
(Trifolium pratense). Cultivated crops vary in their susceptibility
to the disease.
susceptible or resistant
Chinese cabbage brussels sprouts, and some turnips
cauliflower, collard, kale, kohlrabi, rutabaga, turnip, and radish
cress, mustard, some turnip and radish varieties, and stock
Infected plants at first appear normal, but as they mature, they
become unthrifty, grow slowly, wilt during sunny days and become stunted.
Usually the disease first appears in the field in scattered groups of
a few to many plants. In successive seasons, the entire field may become
infected. Affected plants have large galls or clubs on the roots and will
produce a poor crop, or no crop at all.
intensity is more severe if soils are wet during and after transplanting
or seeding. Some soil types appear to be somewhat non-compatible for survival
of the fungus; and in such soils, the persistence of the fungus in the
absence of a host may be as short as three years. Preliminary observations
suggest that poorly drained, sandy soils, low in organic matter, may be
non-compatible, whereas well-drained clay type soils are compatible; and
the fungus will persist for many years, ten years or more. The disease
is not seed-borne. But, the fungus is readily spread in surface runoff
water, irrigation water, contaminated equipment, and to some extent by
roving animals. The use of contaminated transplants is the chief means
of spread of the causal agent.
The fungus of this disease is the soil-borne Plasmodiophora bassicae,
an obligate parasite that can only live and cause disease in crops of
the mustard family and four species in other families. There may be specialized
forms (races) of the fungus that vary in the intensity of disease caused
on different crops and ability to survive in different areas. The fungus
produces resting spores that can remain alive for years in some soil types
in the absence of susceptible crops.
The practical control of this disease emphasizes avoiding the introduction
of the fungus in a field. The importance of never planting contaminated
lots of plants cannot be overstated. Once the disease is present in a
farming operation, control measures are difficult, expensive, and not
very effective. Resistant varieties of some of the crops have been reported,
but are not acceptable for commercial markets.
Always use plants certified by the official state certifying agency.
Plants from outside of North Carolina, by law, must be inspected by
the North Carolina Department of Agriculture upon arrival. If even a
trace of club-root is present on a few plants, or is known to be present
in the plant bed, reject the entire lot.
Locate plant beds
at sites without a history of club-root. Do not irrigate from sources
that might be contaminated from cabbage fields.
equipment after working in a field suspected of having the club-root
fungus by thorough washing followed by spraying all surfaces with a
disinfectant such as "Lysol," formaldehyde, etc.
Grow cabbage and
related crops once every three to five years with crops not in the mustard
family. For this rotation to be effective, it is necessary that susceptible
weeds and volunteer plants (see section on Hosts) be excluded.
Broadcast and incorporate
1500 pounds of "quick lime" (calcium hydroxide) per acre just before
planting or seeding.
cabbage, cauliflower, broccoli, and brussels sprouts, use 6 pounds of
Terraclor 75WP per hundred gallons of water per acre; use 3/4 pint per
Disease Information Notes Home Page
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Carolina Agricultural Chemicals Manual
with a specific problem, contact your local
North Carolina Cooperative Extension Service
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of specific chemicals are based upon information on the manufacturer's
label and performance in a limited number of trials. Because environmental
conditions and methods of application by growers may vary widely, performance
of the chemical will not always conform to the safety and pest control
standards indicated by experimental data. All recommendations for pesticide
use were legal at the time of publication, but the status of registration
and use patterns are subject to change by actions of state and federal
regulatory agencies. 08/91/1500
North Carolina Cooperative Extension Service
Distributed in furtherance of the Acts of Congress of May 8 and June 30,
Employment and program opportunities are offered to all people regardless
race, color, national origin, sex, age, or disability. North Carolina
University at Raleigh, North Carolina A&T State University, U.S. Department
Agriculture, and local governments cooperating.
Dec. 2000 by A.V. Lemay