The document discusses several physiological disorders that can affect cabbage crops, including internal tipburn, black petiole, and pepper spot. It also covers issues like edema, J-rooting, magnesium deficiency, blindness, and leaf tipburn. For each disorder or issue, it provides the symptoms and possible remedies. It concludes by covering nutrient deficiencies for various minerals like nitrogen, phosphorus, potassium, calcium, magnesium, and others; listing the symptoms and recommended corrections for each deficiency.
4. INTERNAL TIPBURN
Internal tipburn of cabbage
can be an economic problem
in the United States and
northern Europe. Although
this disorder probably has
occurred to a limited extent
for a long time, the incidence
has become higher in recent
years because of the more-
intensive production practices
currently used to obtain
higher yields. White, red, and
savoy cabbage are all
affected.
Symptoms
5. BLACK PETIOLE
Black petiole or black midrib
is an internal disorder of
cabbage that has been
occasionally noted in recent
years. It was first described in
New York in 1967. As heads
approach maturity, the dorsal
side of the internal leaf
petioles or midribs turns dark
gray or black at or near the
point where the midrib
attaches to the core.
The.affected area may be
quite limited or may extend
for 2 or 3 inches along the
midrib
Symptoms
6. PEPPER SPOT
Pepper spot or black speck
is yet. another nonparasitic
disorder of cabbage. This
disease, which was first
described in 1919, is
apparently quite widespread
in the United States and in
Europe. It occurs with
varying severity on the outer
leaves of the head, but often
can be seen deep in the
center of the head
Symptoms
7. OEDEMA OF CABBAGE
Oedema is a physiological response of the plant to
excessive soil moisture during periods of cool
nights and warm, humid days. Many small scabby
lesions form on the underside of the cabbage
leaves. Avoid irrigation during times when day-night
temperature variations are great. Oedema may be
confused with thrips damage
8. J-ROOTING
This is caused by poor transplanting practices,
when seedlings are pushed into the soil in such a
way that the roots are not vertical, but bent to one
side. This has a greater effect on growth than you
would think. A month or so later the plants will be
stunted and usually unmarketable.
10. BLINDNESS (CABBAGE )
Causes: Damage to terminal growing point due to
low temperature, cutworm damage or rough
handling of transplants
Symptoms: Plants have lost their terminal growing
points. The leaves that develop are large, dark,
green, thick and leathery. The plant does not
produce a marketable head or curd.
Remedy: Handle transplants carefully, control
cutworms and avoid low temperatures.
Symptoms
11. LEAF TIPBURN (CABBAGE)
Tipburn, cauliflower Carl
Rosen, University of
Minnesota
Cause: localized calcium
deficiency due to water
stress or uneven watering
even with adequate levels
of soil calcium present
Symptoms: Younger leaves
show signs of browning at
the tips (see photo). In
cabbage, the browning can
be seen only after the head
is cut open.
Symptoms
14. PotassiumDeficiency
SymptomsAppears first on
oldest cabbage leaves as
spots shiny green leaves turn
dull green, leaf margins turn
a yellowish green followed by
withering mature heads are
loose and smaller. In K-
deficient cauliflower, leaf tips
turn brown, leaves turn
inward and can have a
crinkled surface.
Correction MeasureFoliar
spray of K2SO4 1% twice at
weekly intervals.