1) Ascochyta blight, caused by the fungus Phoma rabiei, is a major disease of chickpea that can cause 100% yield losses. 2) It has a worldwide distribution, affecting over 35 countries across six continents. India and Pakistan are among the regions most impacted by epidemics. 3) The disease affects all above-ground plant parts, appearing as pale lesions on leaves, stems, and pods. If left unchecked, it can destroy entire crops.

1. SUBMITTED BY COURSE TEACHER
POORANI. S Dr. S. PARTHASARATHY
ID. No. 2016021031 Asst. Prof., (Plant Pathology)
COLLEGE OF AGRICULTURAL TECHNOLOGY
Affiliated to Tamil Nadu Agricultural University, Coimbatore
Kullapuram, Via Vaigai dam, Theni-625 562
ASCOCHYTA BLIGHT OF CHICK PEA

2. AASCOCHYTA BLIGHT OF CHICKPEA
©https://mobile.abc.net

3. SIGNIFICANCE
• Chickpea is the third most important food legume
crop.
• It is grown in 11m ha with 9 million ton
production.
• Ascochyta blight of chick pea is caused by fungal
pathogen Phoma rabiei (formerly known as
Ascochyta rabiei).
• Grain yield and quality losses up to 100%.

4. GLOBAL DISTRIBUTION
• The disease is worldwide in distribution, first described
in India by Butler in 1911 and occurs in epidemic
forms in Punjab and Jammu.
• The occurrence of AB of chickpea has been reported
from 35 countries across six continents.
• 20 epidemics region occurred in Pakistan, India and
European countries.
• In 1998 there was a serious outbreak of the disease in
Victoria, South Australia and New South Wales which
destroyed many crops.

5. GLOBAL DISTRIBUTION OF ASCOCHYTA BLIGHT OF CHICKPEA
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6. INDIA LEVEL DISTRIBUTION
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7. SYMPTOMS
• The initial symptom of the disease appears near
the tip of young shoot and top most leaves.
• The fungus attacks all above-ground plant parts
like leaves, stems and pods at any stage of the
plant growth.
• But plants are most susceptible to disease during
flowering.
• Pale green-yellow, circular, depressed lesions
appeared on leaves and pods.

8. SS
• Elongated lesions on petioles and stem.
• Stem lesions often gridle the stem of the plant.
• Pycnidia may be formed on these lesions usually
in concentric rings.
• Infected seed may discoloured, shriveled and
pycnidia may be present on such seeds.

9. LEAF LESION
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10. CCONCENTRIC RINGS IN PODS
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11. IINFECTED SEEDS INFECTED STEM
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12. SYSTEMATIC CLASSIFICATION
• Kingdom :Fungi
• Phylum :Ascomycota
• Class :Dothideomycetes
• Sub class :Pleosporomycetidae
• Order :Pleosporales
• Family :Didymellaceae
• Genus :Ascochyta
• Species :A.rabiei (Pass) Labr., (1931)

13. PATHOGEN CHARACTERS
• Ascochyta rabiei (exists both as an anamorph
(asexual) and teleomorph (sexual) Didymella
rabiei.
• Mycelium – pale cream coloured.
• Fruiting bodies
Asexual- Pycnidia
Sexual- Pseudothecia

14. • Spores
Asexual- Pycnidiospores
Sexual- Ascospores
• The conidia are oval to oblong, one to two celled,
thin walled and hyaline but pinkish in mass and
measuring 9-20 × 3-6µ.
• They germinate in water with long germ tubes.

15. CONIDIA OF ASCOCHYTA BLIGHT OF CHICKPEA
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16. PYCNIDIA OF ASCOCHYTA BLIGHT OF CHICKPEA
©agementnetwork.org

17. ©slideshare.net

18. DISEASE CYCLE OF ASCOCHYTA BLIGHT OF CHICKPEA
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19. EPIDEMIOLOGY
MODE OF SPREAD
• PRIMARY SPREAD:
Seed transmission ensures random distribution of the
pathogen in a field.
• SECONDARY SPREAD:
Conidia and ascospores are responsible for
secondary spread of the disease.
It may also be dispersed by rain splashes, wind,
water flow and contaminated machinery.

20. MODE OF SPREAD:
• The fungus survives on the infected seeds and
plant residues.
• The fungus survives for some time in the host
tissue, both in the form of pycnidia and peridia
and perithecia.
• It is seed borne both internally and externally.

21. FAVOURABLE CONDITION
• Temperature between 20-25ºC, leaf wetness
period of 10-17 h are favourable for disease
development.
• The rainfall should be more than 350mm and
followed by high humidity favours this disease.

22. MANAGEMENT
• Sow disease free seed.
• Removal and destruction of dead plant debris.
• Follow crop rotation.
• Intercrop with wheat, barley and mustard.
• Grow resistant varieties like Pusa 408, Pusa 417,
ICL 6328.

23. • Seed treatment with Carbendazim (Bavistin) @
1g/kg of seed.
• Hot water seed treatment (52ºc for 10 min) to
lower the infestation.
Fungicides:
• Spray Mancozeb (Indofil M – 45) @ 2.5 g/lit.
• Spray wettable sulphur @ 2.3 g/lit of water.

24. MANCOZEB
©indofilcc.com

25. REFERENCES
Singh.S.K., D.Singh and A.Kumar, 2017, Plant Diseases and
Their Management, Kalyani Publishers, New Delhi.
Singh.R.S.,Vinod kumar Jain, 2018 , Plant Diseases,
Scientific International (Pvt.) Ltd., New Delhi.