Bean anthracnose is a seedborne fungal disease caused by Colletotrichum lindemuthianum that affects many legume crops worldwide. The disease causes reddish-brown lesions on pods and leaves that produce pink spores in moist conditions, reducing crop yields. The fungus spreads primarily via contaminated seeds and crop debris, with secondary spread by rain splash and wind under favorable conditions of 13-26°C, 92% humidity, and moderate rainfall. Management strategies include crop rotation, seed treatment, fungicide application, soil solarization, and biological controls using Trichoderma viride or plant extracts.

1. COLLEGE OF AGRICULTURAL TECHNOLOGY
(Affiliated to Tamil Nadu Agricultural University, Coimbatore-3)
Kullapuram (Po),ViaVaigai Dam, Theni-625 562
BEAN ANTHRACNOSE
Submitted by Course teacher
RAMYA.V Dr. Parthasarathy.S
2015021106 Assistant Professor (Plant Pathology)

2. HISTORY
• Anthracnose is mainly a seed borne disease caused
by a fungus which has a wide host range on many
legume species.
• In 1921, M. F. Barrus of Cornell University
demonstrated that bean anthracnose is seedborne.

3. OCCURENCE AND DISTRIBUTION
• Anthracnose was first described from plant
specimens obtained in Germany in 1875.
• Later it was spread throughout the world.
• It has been reported in USA, European countries,
Canada, Africa, Uganda, Kenya, Tanzania, Rwanda,
Burundi, Ethiopia and D.R. Congo.

4. HOST RANGE
• Lima bean.
• Scarlet runner beans.
• Mung bean.
• Cow pea and black gram.
• Broad bean.
• Soybean and pea.

5. ECONOMIC IMPORTANCE
• The intensity of this disease ranges from 2 to 100%.
• Greatly affect the yield, seed quality and marketability
of the crop.
• The disease causes greater losses in North, Central and
South America, Europe, Africa, Australia, Asia, Brazil,
Mexico, and Colombia.

6. SYMPTOMS
• Leaves, stems and pods of bean plants are susceptible
to infection.
• Small reddish-brown, slightly sunken spots form on
the pods and rapidly develop into large, dark-sunken
lesions.

7. • In moist weather, masses of pink spores develops on
the lesions.
• Infection of the leaves causes blackening along the
veins particularly on the under surface.

8. www.researchgate.com

9. CONIDIA DEVELOPMENT

10. DISEASE CYCLE

11. SYSTEMATIC POSITION
Kingdom : Fungi
Phylum : Ascomycota
Class : Sordaiomycetes
Sub class : Incertae sedis
Order : Phyllachorales
Family : Phyllachoraceae
Genus : Colletotrichum
Species : C. lindemuthianum

12. CAUSAL ORGANISM
• Asexual stage : Colletotrichum lindemuthianum.
• Sexual stage : Glomerella cingulata.
• The fungus produced hyaline, single celled, oblong,
sickle shaped conidia.

13. MODE OF SPREAD
• Primary spread :
Contaminated seed and crop debris.
• Secondary spread :
Rain splash and wind.

14. FAVOURABLE CONDITIONS
• Temperature – 13-26° C.
• Relative Humidity – 92%.
• Moderate rainfall.

15. CULTURAL MANAGEMENT
• Removal of infected plant debris.
• Using diseased free seeds.
• Crop rotation with non host crops like cereals and
solanaceous crops.
• Giving adequate plant spacing.
• Avoid overhead irrigation.

16. CHEMICAL MANAGEMENT
• Seed treatment with Mancozeb @ 3g/kg.
• Carbendazim foliar spray @ 0.5 kg/ha have
been suggested to reduce anthracnose severity and
incidence.
• Difenoconazole 87.5g/ha effectively reduce this
disease.

17. PHYSICAL MANAGEMENT
• Practicing soil solarization for one month before
sowing resulted in the reduction of both severity and
incidence.
• Hot water seed treating by soaking at 64 to 74ºC for
15 hrs has been reported to kill the fungus in infested
seeds without reducing germination.

18. BIOLOGICAL MANAGEMENT
• Application of Trichoderma viride as seed dipping
and soil drenching was effective against this
pathogen.
• Neem seed extract effectively inhibited both
germination of conidia and mycelial growth.
• Lawsonia inermis seed treatment significantly
improved seedling emergence.

19. REFERENCES
• www.researchgate.com
• www.sciencedirect.com
• https://www.gardeningknowhow.com
• www.moaf.gov.bt