3 Crops (Barley, Millet and Maize) of Cereal and their Main Diseases

1. 3 Crops of Cereal and their
Main Diseases

2. What will be covered?
• What is Barley?
– Powdery Mildew
– Covered Smut
– Loose Smut
• What is Millet?
– Green ear or downy mildew
– Grain smut
– Ergot
• What is Maize?
– Smut
– Common Rust
– Leaf Blight

3. Barley
• Barlay is a member of
the grass family and a
major cereal grain
• It is used as a
component of
various health foods,
soups and stews, and
in barley bread of
various cultures
• Barley is cultivated on a
small scale in Pakistan

4. Powdery Mildew
• Pathogen: Blumeria graminis
• Symptoms:
– can be found on leaves, stems and ears
– white pustules appear eventually become
black spore (cleistothecia) towards the
end of the season

5. Life Cycle

6. Covered Smut Loose Smut
• Pathogen: Ustilago hordei
• Symptoms:
– Ear emergence
– In which ears seem to be
normal but grains appear
to be covered in a thin
membrane
– Grains have been replaced
by masses of black spores
– Membrane is easily
ruptured and as spores are
released the symptoms
become similar to those of
loose smut
• Pathogen: Ustilago nuda
• Symptoms
– Ear emergence
– Replaced by a mass of
black fungal spores
– The spores are released as
soon as the ear emerges,
leaving only the bare
remains of the ear rachis
– Blackened ears are so
obvious in the crop at ear
emergence the disease
appears to be very severe

8. Life Cycle

9. Millet
• Grown under erratic
distribution of annual
rainfall, high mean
temperature and
depleted soil fertility
• These are currently the
fourth cereal in Pakistan
• It is mostly confined to
the desert and mountain
(Thar-Cholistan and
Kohistan) area

10. Green ear or downy mildew
• Pathogen: Sclerospora graminicola
• Symptoms:
– Ear formation stage
– Leaves become distorted, twisted, crinkled and
lose their green colour, become white and later
turn brown
– The ears are transformed in to green leafy
structures with enlarged glumes, turning wholly or
partially into loose heads
– The affected portions are sterile and they do not
produce grains

11. Life Cycle

12. Grain smut
• Pathogen: Tolyposporium penicillariae
• Symptoms:
– Infected grains are thickened, slightly elongated
– Covered by tough and blackish green membrane
filled with fungal spores
– These are present singly or in groups
– Usually a one side of the ear or towards its base
– Scattered or collected together in patches on the
ear

13. Life Cycle

14. Ergot
• Pathogen: Claviceps purpurea
• Symptoms:
– The causal fungus only attacks the ear at
flowering, replacing the grain in a few spikelets by
a hard, purple black sclerotium, known as an ergot
– Such ergots can be very large, up to 2cm in length

16. Maize
• Cultivated as multipurpose
food and forage crop,
generally by resource poor
farmers using marginal land
• In Pakistan, it is the third
most important cereal after
wheat and rice
• An important crop in Pakistan
in terms of its food for human,
feed for poultry and fodder for
livestock utilization and as a
raw material for the industry

17. SMUT
• Pathogen: Ustilago maydis
• Symptoms:
– White to grayish-white galls (soft tumors) develop
on any part of the plant.
– These galls are light coloured in early stages,
become blackish on maturity and filled with black
powder
– Large sized galls involving the entire head

19. Rust
• Pathogen: Puccinia sorghi
• Symptoms:
– Recognized by small, elongate, powdery pustules
over both surfaces of the leaves
– Pustules are dark brown in early stages of
infection; later, the epidermis is ruptured
– Lesions turn black as the plant matures

21. Anthracnose leaf blight
• Pathogen: Colletotrichum graminicola
• Symptoms:
– The disease is present in warm, humid environments
with a foliar disease phase and a stalk rotting phase.
– The most severe damage is caused by the stalk rot
phase.
– Foliar damage can be observed at different stages of
plant development
• In the early seedling stage, leaves show irregular, oval-to-
elongated lesions with characteristic yellow-to-reddish-
brown margins
• In later stages of plant development, similar lesions can be
observed in the upper leaves of infected plants, especially in
those where stalk rot symptoms have already developed

23. Control:
• Use resistant varieties
• Use Fungicide seed
– Always have new seed treated with fungicide
• Spraying with a foliar fungicide
• Field sanitation
• Do not sow diseased seed
• Collection and burning of diseased plants or
plant parts, as soon as they appear
• Use of 2-3 year crop rotation