Fungi constitute the largest number of plant pathogens and are responsible for a range of serious plant diseases. Most vegetable diseases are caused by fungi. They damage plants by killing cells and/or causing plant stress. Sources of fungal infections are infected seed, soil, crop debris, nearby crops and weeds.

1. SHRI SHANKARACHARYA
MAHAVIDYALAYA JUNWANI, BHILAI
COMMANFUNGALDISEASEOF CROPPLANT
Dr. Racahna Choudhary
HOD Microbiology

2. SYNOPSIS :-
 Introduction
 Term and definitions
 Plant pathology
 Selected plant disease (fungal disease)
 Late blight disease of potato
 Tikka disease of groundnut
 Red rot of sugarcane
 Conclusion
 References

3. INTRODUCTION :-
 The study of
microbial disease of
crop plant is called
plant pathology.
 Plant pathology is a
branch of botany.

4. DEFINITION :-
 Several definition of diseases of plant s
have been proposed by different
scientists from time to time, these are :-
 Anon (1950) :- Defined disease as
“harmful deviation from normal functioning
of physiological process”.
 According to the modern concept :-
Disease is an interaction among the host,
parasite and environment.

5. COMMAN FUNGAL DISEASES :-
 The plant diseases are caused by
pathogens.
 Fungal diseases
1. Late blight of potato,
2. Tikka disease of groundnut,
3. Red rot of sugarcane.

6. LATE BLIGHT OF POTATO :-
 Introduction :-
 The disease causes blight symptom which
appears middle to late in the season.
 late blight of potato was available in that
area as an endemic disease.

7.  Host : Solanum tuberosum.
 Symptoms : -
 On foliage
 Inside the tuber
(a). During growing season
(b). During harvest
Fig. Late blight of potato : Blighted
leaf.
Fig. Late blight of potato : Diseased
tuber

8. CAUSAL ORGANISM:-
 Phytopthora infestans, belongs to the
subdivision Mastigomycotina under the
division Eumycota.
Fig. Late blight of potato : Section of diseased leaf showing sporangiophore coming
out through stomata.

9. Fig. Sporangium on branched
sporangiophore.
Fig. Single sporangium. Fig. Germination of sporangium
by prpducing zoospore.
Fig. Direct germination of
sporangium.
Fig. Single Oospore.

10. DISEASE CYCLE:-

11. DISEASE MANAGEMENT:-
 Cultural method
 Physical methods
 Chemical methods
 Brestan (1kg/ha),
 Dithane M-45 (2 kg/ha)
 Difolitan 80WP (2.5 kg/ha)

12. TIKKA DISEASE OF GROUNDNUT :-
 Introduction :-
 The disease, caused by Cercospora, is
also known as Cercospora leaf spot.
 Host :- Arachis hypogea.

13. SYMPTOMS :-
Fig. Tikka disease of groundnut
(Symptoms on leaflets)

14. CAUSAL ORGANISM :-
 Cercospora
arachidicola (early
leaf spot) :-
 Cercosporidium
personatum (late leaf
spot) :-
Fig. (Cercospora arachidicola)
Stroma bering conidiophores and
conidia.
Fig. (Cercosporidium personatum)
Section through infected leaf
showing conidiophores and
conidia.

15. DISEASE CYCLE:-

16. DISEASE MANAGEMENT:-
 Cultural method :-
 Sanitation.
 Crop rotation.
 Early sowing.
 Chemical methods :-
 Seed treatment.
 Foliar spray

17. RED ROT OF SUGARCANE :-
 Introduction :-
 The disease is prevalent in most of the
sugarcane growing areas of the world in
moderate to most destructive from.
 Host :- Saccharum officinarum.

18. SYMPTOMS :-
 On stem.
 Inside steam.
 On leaf.
Fig. Red rot of sugarcane : A-B. Dry, shriveled cane due to pathogenic attac
C-D. Reddening (black in figure) of the pith with white transvers blotche
Fig. Showing symptoms
on mid rib.

19. CAUSAL ORGANISM :-
 The causal organism is Colletotrichum
falcatum.
Fig. Red rot of sugarcane : (Colletotrichum falcatum.)
A. Acervuli, B. Conidia and C. Germination of conidia.

20. DISEASE CYCLE:-

21. DISEASE MANAGEMENT:-
 Cultural method :-
 Field sanitation.
 Selection of seed sets.
 Crop rotation.
 Physical methods :-
 Hot water treatment.
 Hot air treatment.
 Chemical methods

22. CONCLUSION :-
 Fungi commonly enter in the root by
hyphae developed on germination of
different type of spores and gradually
grow upwards through the xylem vessel
and subsequently block the vessel by
mycelium and further cause infection.

23. REFERENCES
• Plant disease R.S.Singh 8th edition)
• Agriculture Microbiology By G. Rangaswami
& D. J. Bagyaraj
• Text book of botany by Singh, Pandey and
Jain
• Fungi by Vashishta

24. Thank you