2. Damping off
(Rhizoctonia solani, Phytobhthora spp. Pythium spp.)
It is very common fungal
disease of seedlings in nursery.
The affected seedlings rot at
collar region and topple down
on the ground.
The base of stem is brown,
constricted, dry and demarked
by deep brown and reddish
borders.
High temperature, excessive
salt concentration, excessive
soil moisture or water logging
and poor soil aeration are the
main predisposing factors that
favor damping off disease.
3. Control measure
Follow long crop rotation
with cereals.
Sterilize the soil with 1%
formaline.
Soak the seeds in tap water
for 30 minutes followed by
hot water dip at 52˚C.
Provide good drainage.
Maintain moderate soil
moisture in nursery.
Always sow the seed
sparsely to avoid
overcrowding of seedlings.
Drench the nursery beds
with 0.25% Ridomil MZ-
72 WP solution.
4. Black rot
(Xanthomonas campestris)
It is seed borne disease by
which cauliflower is affected
both in nursery and in field.
The plant may be affected at
any stage during its growth.
Infected leaves show
yellowing at margins and the
necrosis towards the center of
the leaf, forming V-shaped
area .
The veins become brown or
dark and vascular regions of
the main stem discolored.
Leaves fall prematurely due to
formation of abscission layer.
5. Control measure
Follow long crop
rotation of at least 3-5
years.
Treat the seed with
hot water at 52˚C for
an hour.
Protective spray with
Indofil M-45 @
100ppm and repeat at
least 8-10 days
interval.
Small rotten area on
the curd may be cut
with knife and painted
with Bordeaux
mixture @ 4: 4: 50.
6. Sclerotinia rot
(Sclerotinia sclerotiorum)
The first symptoms of
disease appears as wet soft
lesion on cauliflower curd,
and leaf scar on stump
region left behind due to
defoliation of older leaves.
Later, these spots enlarge
into watery rotten mass of
tissues.
The affected parts of seed
crops wilt and die later on.
7. Control measure
Follow crop rotation
with cereals.
Pick up and destroy
the diseased leaves.
Spray the crop with
carbendazim 0.05%
combine with
mancozeb 0.2%.
8. Downy mildew
Peronospora parasitica)
The disease is prevalent in
cooler regions of the world.
Small chlorotic, irregular,
translucent, light green
lesions usually delimited by
the veins appear on leaves
under cool and moist
conditions.
The young leaves less
susceptible than older ones.
Infection occurs more readily
on lower surface than on
upper ones.
The infected curds exhibit
brownish to blackish look.
9. Control measure
Follow long crop
rotation with cereals.
Treat the seed with
Captan 2.5-3.0 g/kg
of seed.
Adopt the clean
cultivation.
Spray the crop with
Ridomil MZ-72 or
mancozeb at 0.25% at
10-15 days interval
starting from the first
appearance of
symptoms.
10. Alternaria leaf spot
(Alternaria brassicicola)
The spots appears as small
dark colored areas, which
expand rapidly to form
circular lesion up to 1.0
cm dia.
The enlargement of spots
may be in concentric
circles.
In some conditions, the
cauliflower curd also
show browning ,
beginning at the margins
of flower clusters.
11. Control measure
Depending up on
infection, 2-4
sprays of Indofil
M-45, Difolatan at
0.2%, or Blitox @
0.5-0.75% at 15
days interval are
effective.
12. Bacterial soft rot
(Erwinia carotovora)
The first symptoms
appear on fleshy
affected tissue as
small water soaked
lesions, which
enlarge rapidly.
The affected plants
show a soft , slimy,
foul smelling rot
and fail to bolt.
13. Control measure
Spraying the
streptocycline or
plantomycine @ 500
ppm in combination
with copper
oxychloride 2000 ppm
at fortnightly interval
starting from
appearance of first
symptoms of disease.
14. Wire-stem
(Rhizoctonia solani)
This is mostly appears in
cabbage, in warm and
humid areas and seriously
affects the crop at seedling
stage.
The infested young
seedlings show soft and
water soaked spots on the
stem near collar region,
and as a result, the
seedling topple down.
The lower part of the stem
often shows dark
discoloration over a length
of several centimeters.
The portion hard and
thinner than the healthy
portion, hence, it is named
as wire-stem.
15. Control measure
Follow integrated disease
management.
Plough the field deep in hot
summer months.
Use varieties resistant to wire-stem.
Soak the seed in hot water of 52˚C
for half an hour.
Use only healthy seedling for
transplanting.
Plant the seedling shallow.
Use compost and photodegradable
plastic mulch.
Follow field and Phyto-sanitation.
Provide proper drainage.
Apply selective fungicides or
methyl bromide in nursery beds.
16. Yellow-wilt
(Fusarium oxysporum)
Cabbage and cauliflower
highly susceptible to yellows
when grown in warm weather.
The foliage of infected plants
turn yellow, dies and
eventually drops off.
The symptoms appear first on
lower leaves.
The disease may affect the
plants at any stage.
young seedling show
damping off.
Heavy infection causes death
of the plants but sudden
withering does not usually
occur.
17. Control measure
Follow long crop
rotation.
Sterilize the soil
with steam.
Dipping of roots in
1% zinc dimethyl
ditiocarbamate for
30 minutes before
transplanting.
18. Black leg
(Phoma lingam)
It is appearing frequently in
cabbage growing areas of
Kullu Valley.
On seedling, black pucnidia
are visible as small dots on the
hypocotyl and on the cotyledon
of young plant resulting into
their death.
In advance stages stem shows
sunken grayish brown oval
spots, often with purple and
black margins.
On leaves is causes sunken,
irregular grayish spots with a
purplish to black margin.
19. Control measure
Use clean seed as a
preventive measure.
Follow long crop
rotation.
Provide hot water
treatment at 50˚C for
30 minutes.
Treat the seed with
Benomyl slurry
combine with
Thiram.
Follow field and
phyto-sanitary.
20. Club root
(Plasmodiophora brassicae)
Especially in temperate region.
It affect the underground
portion but symptoms on
above ground portion are
apparent only in advance
stages.
Formation of small or large
spindle like spherical, club
shaped swelling on roots and
rootlets.
The hypertrophy of tissue
disrupts water supply , which
result in pale green to
yellowish foliage, flagging and
wilting of plants.
Club roots is particular
prevalent on soils with a pH
below 7.
21. Control measure
Raise the pH of acidic soil by
adding lime.
Raise the crop in well-drained
soil with pH slightly above
neutral.
Sterilize the nursery bed’s.
Use fungicides like
carbendazim, Deconil,
Thiophanate methyl, Zineb,.
The most practical control
measure is crop rotation.