- Guava anthracnose is caused by the fungal pathogen Gloeosporium psidii. It affects guava plants and fruits. - Symptoms include die back of branches, leaf spots, and sunken lesions on fruits. The disease is favored by moist conditions and temperatures between 10-35°C. - The pathogen can survive on plant debris and spreads via airborne spores. Management involves resistant varieties, pruning, fungicide sprays, and post-harvest fruit dips.

1. COLLEGE OFAGRICULTURAL TECHNOLOGY
(Affiliated to Tamil Nadu Agricultural University, Coimbatore-3)
Kullapuram (Po),ViaVaigai Dam, Theni-625 562
GUAVAANTHRACNOSE
Submitted by Course teacher
R.GOKULNATH. Dr. S. Parthasarathy
2015021O39 Asst. Prof. (Plant Pathology)

2. GUAVAANTHRACNOSE
• CASUAL ORGANISMS: Gloeosporium psidii (Anamorph)
Glomerella cingulata (Teleomorph)
• SYNONYMS : Colletotrichum gloeosporioides

3. DISTRIBUTION
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4. HOST RANGE
A variety of fruits including
 Mango
 Papaya
 Citrus
 Pomegranate
 Guava
 Grapes

5. HISTORY & SIGNIFICANCE
• Anthracnose is most common and important disease of guava in india.
• Particularly in U.P., Punjab and karnataka
• It was first reported from Saharanpur (UP) in India by Mehta (1951)
• It cause serious post harvest rotting of guava fruits

6. • In Karnataka disease was reported by Rawal during 1993.
• Die back phase is caused by Gloeosporium psidii resulting in the death
of plants was observed at Allahabad (Tandon and Agarwal, 1954)
• But this phase was not observed at Saharanpur.
• This disease phase is also reported in pakistan, taiwan, thailand
and bangladesh

7. Symptoms
• The disease mostly affects the tender parts of the tree such as young leaves,
shoots, flowers and fruits.
Occurs in two phases
Die back phase Fruit and leaf infection phase

8. DIE BACK PHASE
• The plant begins to die backwards form the top of a branch while the
young shoots, leaves and fruits are readily affected.
• The greenish colour of the growing tip is changed to dark brown
• Later to black necrotic areas extending backwards causing the die back.
• The young fruits droop down and dry up.

9. FRUITS AND LEAVES INFECTION PHASE
• Fruit and leaf infection is generally seen in rainy season crop.
• Small pin-head spots are first seen on unripe fruits, which gradually
enlarge to form sunken, circular spot of dark brown to black in color.
• Minute black stromata appear in the center of the lesion, which
produce creamy spore masses in moist weather.
• The unripe fruits become harder and corky.

10. SYMPTOMS
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11. ©www.vnrnursery.in
Corky and hardy natureSunken spots on fruits

12. DISEASE CYCLE OF Gloeosporium psidii
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13. PATHOGEN CHARACTERS
• Brown to dark brown coloured acervuli are formed on the affected
parts of the plant.
• Setae and conidia are formed in the acervuli. Mycelium is
intercellular, branched and light brown in colour.
• Conidiophores are hyaline and small, setae are long, tapering at the
end, dark brown to black in colour.
• Conidia are formed at the tip of the conidiophores and are sickle-
shaped, unicellular, hyaline.

14. MODE OF DISPERSAL
SURVIVAL
Pathogen can survive on infected plant debris and is very
easily spread.
PRIMARY SPREAD
Air borne spores develops on dead leaves, twigs and mummified
fruits
SECONDARY SPREAD
Infected plant materials

15. FAVOURABLE CONDITIONS
• Closer planting without canopy management
• The acervulli with pink spore mass are produced in moist weather on diseased
twigs and mummified fruits
• Dew and rain encourage spore production
• Temperature between 10℃ to 35℃ with best 24℃ to 28℃
• The disease appears in epidemic form, during August to September. It is also
noticed in December after which the older leaves and twigs remain immune from
attack

16. IDM
 Cultural method
•Use resistent varieties Apple guava (deep red fleshed), Apple shaped
seedling, Behat Coconut, Red Chittidar, Muzaffamagar, Bulandshahar,
Lucknow-49.
•Well-managed trees escape the attack of the disease
•Proper canopy management

17. Mechanical method
• Pruning of diseased twigs
• Burning of fallen leaves and fruits.
Biological method
• Application of Streptosporangium pseudovulgare on fruits before
emergence the symptom.

18.  Chemical method
• Spraying with Copper oxychloride 50 % WP @ 4 gm/ lit
• Captan 75 % WS @ 2.5 gm/lit
• Mancozeb 75 % WP @ 2.5 gm/litre of water.
• Effective control of anthracnose can be achieved by sprays of Bordeaux
mixture (3:3:50) at 7 days interval.
• For post harvest treatment 20 min dip treatment in 500 ppm tetracycline is
effective