This document summarizes the common diseases that affect mustard crops, including their symptoms and causal organisms. It discusses 12 different diseases: Anthracnose caused by the fungus Colletotrichum higginisianum, Alternaria leaf spot caused by Alternaria spp., Cercospora leaf spot caused by Cercospora brassicicola, Downy mildew caused by Peronospora parasitica, White spot caused by Pseudocercosporella capsellae, Sclerotinia rot caused by Sclerotinia sclerotiorum, Clubroot caused by Plasmodiophora brassicae, Black root caused by Aphanomyces raphani

3. The Mustard Crop Diseases
A
Lecture To ToT trainees ( FFS)
By
Mr. Allah Dad Khan
Provincial Coordinator IPM KPK
MINFAL Pakistan

4. Anthracnose
Colletotrichum higginisianum
Symptoms
• Small circular or irregularly
shaped dry spots which are gray
to straw in color on leaves; a high
number of spots may cause the
leaf to die; lesions may coalesce
to form large necrotic patches
causing leaves to turn yellow and
wilt; lesions may split or crack in
dry centers; dry sunken spots on
roots which enlarge and turn gray
or brown
• Cause
• Fungus

5. Alternaria leaf spot (Black spot, Gray spot)
Alternaria spp.
Symptoms
• Small dark spots on leaves
which turn brown to gray;
lesions may be round or
angular and may possess a
purple-black margin; lesions
may form concentric rings,
become brittle and crack in
center; dark brown elongated
lesions may develop on stems
and petioles
• Cause
• Fungus

6. Cercospora leaf spot (Frogeye leaf spot)
Cercospora brassicicola
Symptoms
• Angular or circular green to
gray spots with brown
borders on leaves; plant
defoliation may occur in the
case of a severe infestation
• Cause
• Fungus

7. Downy mildew
Peronospora parasitica
Symptoms
• Irregular yellow patches on
leaves which turn light
brown in color; fluffy gray
growth on the undersides of
the leaves
• Cause
• Fungus

8. White spot
Pseudocercosporella capsellae
Symptoms
• Small, necrotic, brown spots
on leaf tips or margins that
matures to light gray or
white with the original dark
spot in center; margins of
lesions may be darker;
lesions may coalesce to
form large chlorotic areas
and cause defoliation
• Cause
• Fungus

9. Sclerotinia rot (White mold)
Sclerotinia sclerotiorum
Symptoms
• Irregular, necrotic gray
lesions on leaves; white-
gray leions on stems;
reduced pod set; shattering
seed pods
• Cause
• Fungus

10. Clubroot
Plasmodiophora brassicae
Symptoms
• Slow growing, stunted
plants; yellowish leaves
which wilt during day and
rejuvenate in part at night;
swollen, distorted roots;
extensive gall formation
• Cause
• Fungus

11. Black root
Aphanomyces raphari
Symptoms
• Small black-blue areas on roots
which expand and girdle taproot;
roots become constricted at site
of lesions; black discoloration
extends into root
• Cause
• Fungus
• Comments
• Fungus can survive in soil for
prolonged periods
• Management
• Control depends on crop rotation
with non-brassica species

12. Wirestem (Damping-off)
Rhizoctonia solani
Symptoms
• Death of seedlings after
germination; brown-red or
black rot girdling stem;
seedling may remain
upright but stem is
constricted and twisted
(wirestem)
• Cause
• Fungus

13. Black rot
Xanthomonas campestris
Symptoms
• Seedlings develop wilted
yellow to brown leaves and
collapse; yellow, V-shaped
lesions on mature leaf
margins; dark rings can be
found in the cross section of
the stem
• Cause
• Bacterium

14. Turnip mosaic
Turnip mosaic virus (TuMV)
Symptoms
• Yellow and green mosaic
patterns on leaves; necrotic
areas on leaves;
veinclearing and chlorosis
may occur in older leaves;
black spots and brown
necrotic streaks on stems;
stunted plant growth ond
reduced yield
• Cause
• Virus

15. White rust lbugo candida
Symptoms
• White pustules on
cotyledons, leaves, stems
and/or flowers which
coalesce to form large areas
of infection; leaves may roll
and thicken
• Cause
• Fungus