This document summarizes the green ear disease, or downy mildew, of bajra crops. It is caused by the fungus Sclerospora graminicola. The disease is widespread in tropical and temperate regions where bajra is grown. Symptoms include chlorosis and leafy growths on panicles, bristles, glumes, stamens and pistils. The fungus can survive in soil for many years as oospores. Management strategies include using resistant varieties, crop rotation, removing diseased plants, seed treatment, and fungicide application.

1. Green Ear of Bajara
By –
Dr. Gunmala Gugalia
Associate Professor
Dept. Of Botany
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2. Introduction- Overview
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DISEASE: Downy mildew or Green ear disease
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PATHOGEN: Sclerospora graminicola
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HOSTS: Bajra / Pearl Millet or Sorghum
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3. Introduction
•
Green ear disease is the most destructive disease of
bajra and widely distributed throughout tropical and
temperate countries of the world.
•
The green ear disease of Bajra is a common disease
and has been reported from several countries
including-
•
India,
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Iran,
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Israel,
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China, Fiji,
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Japan and the countries wherever Bajra crop is grown.
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4. Cont…Introduction
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In India, the disease was first reported and studied by E. J.
Butler (1907) who considered the disease to be sporadic in
nature not causing much damage to the crop.
•
Mitter and Tandon (1930) reported the disease from
Allahabad, Uttar Pradesh and confirmed the observations
of Butler (1907).
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Up to 27-30% losses has been estimated in India.
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5. •
The disease appeared in an epidemic form in Karnataka
and Maharashtra during 1975 causing almost total loss of
the crop.
Cont…Introduction 5

6. Etiology
•
One of the most important diseases of pearl millet
is downy mildew, also known as green ear, caused by the
fungus Sclerospora graminicola (Sacc.)
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•
Kingdom- Straminopila/ Chromista
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Classification
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Phylum- Oomycota
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Class- Oomycetes
Order- Peronosporales
Family - Peronosporaceae

7. Disease Cycle
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The oospores remain viable in
soil for five years or longer
giving rise to the primary
infection on the host seedling.
•
Oospores attached to the seed
also cause primary and
systemic infection of
seedlings.
•
Oospores are formed late in the
season in the necrotic tissues
on the leaves.
•
Secondary spread is through
sporangia, which are active
during rainy season,
disseminated by air and water.
•
Secondary infection may not
develop into systemic infection
but leads to local infection.
•
Seeds formed are internally
infected
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8. Cont…
Etiology
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9. Symptoms
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Two type of symptoms,
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Downy mildew and
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Green ear.
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10. Cont…Symptoms
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Downy mildew-
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Leaves
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Chlorosis starts at the base
of the leaf and soon covers
the entire lamina.
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11. Cont…Symptoms
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Green ear-
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Affecting the ears
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Panicle are drastic
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Bristles , glumes
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Stamens and Pistils
become green and
leafy
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12. Survival and spread
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The oospores remain viable for eight months to ten years
or more in the soil, which makes primary infection in host
plants.
•
The secondary spread of disease starts from sporangia,
which are most active in moist environment.
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13. Favorable conditions
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The atmospheric temperatures between 15-25 °C and
relative humidity above 85%.
Light drizzling accompanied by cool weather is highly
favorable.
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14. Management
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15. Cont…
Management
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Selection of seed from healthy crop
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Rotation of crop
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Removal and burning of diseased plants.
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Spraying with dithane M- 45 helps in controlling
the disease.
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16. •
Seed treatment with 0.1%Agrosan GN and 0.4%
thiram has been reported to control the disease to
50%.
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Use of disease resistant variety like ICMH88088
developed by the ICRISAT, Hyderabad has show
better results.
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Other resistant varities include IP 18292 and 18298.
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Cont…
Management

17. Thank you
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