Plant Pathology, Mycology, Botany

1. Presented by: Amatu Rehman
Hulvova et al. 2013

2.  Classification
 Introduction
 Ergot
 Hymenoascomycetes:
Pyrenomycetes
 Stroma
 Sclerotia
 Life Cycle
 Claviceps Spp.
 Host Range
 Climatic Conditions
 Ergot infection
 Poisioning Due to Claviceps
 Loss in Yield
 Report of Canada
 Pathogenic Life Cycle
 St. Antony’s fire
 Management
 Conclusion
 Refferences

3.  Kingdom: Fungi
 Division: Ascomycota
 Class: Sordariomycetes
 Order: Hypocreales
 Family: Clavicipitaceae
 Genus: Claviceps

4.  Claviceps: ergot of grasses
 It is defined as the perithicial ascoma
producing fungus parasitizing the overies of
of rushes, grasses and sedges and cause ergot
of grasses and ergotism in mammals

5.  Ergot is the French name for a cock’s spur,
referring to the curved, banana-shaped
sclerotia which project from the
inflorescence of infected grasses and cereals
in late summer (Webster & Weber 2007)
 The name ‘ergot’ is derived from an old
French word ‘Argot’ which means Cock’s spur
which represents the dark brown, horn-
shaped fungal structure that projects from
the ripening ears of infected crops(VanDogen
and DeGroot,1995; Nicholson, 2007)

6.  According to the classification of M.E. Barr
2001 which based on phylogenetic analysis
classified them into Pyrenomycetes
 As they belongs to Pyrenoascomycetes, they
producing perithecium fruiting body having
basal hymenium which produced fertile layer
of ascus that are supported by the
paraphyses

7.  Stroma
Lossely arranged
hyphal mass that
produced ascoma
 Scleroticum
Compact hyphal mass
that is perennating
structure for
overwintering and
stored food
Kendrick 2008

8.  Compact hyphal mass that is perennating
structure for overwintering and stored food
Fig: Wheat grains with black colored sclerotia
(Hulvova et al. 2013)

9. Webster & Weber 2007)

10.  Primary inoculum is an ascospore, developed
from overwintered scleroticum
 Ascospores germinate on a grass stigma to form
an intercellular mycelium which grows down to
the base of the ovary
 Growth is upward, within a few days a conidial
stroma develops within the ovary that appears in
the form of Honey droplets on the surface of
florets
 Conidial stage called Sphacelia segatum
 While lower down the sclerotium initial develops
that is overwintering structure and 3cm in length
then normal ovary

11.  Tissues of grains replaced totally by fungal
tissues that’s why its is called replacement
disease
 Scleroticum
Consists of three layers
1. thin purplish-brown rind
2. a central layer of translucent gelatinous
tissues
3. discontinuous layer of mealy white tissue

12.  There are over 40 species of Claviceps,
parasitic on grasses, rushes and, occasionally,
sedges (Alderman, 2003)
 Claviceps spp.
1. C. purpurea, cause of ergot of grasses and
cereals
1. C. sorghi and C. africana which cause
ergot of sorghum (Frederickson et al. 1991)
2. C. paspali on Paspalum
3. C. fusiformis on pearl millet (Pennisetum
typhoides)

13.  Claviceps mostly parasitise the grasses,
rushes and sedges
 C. purpurea effects almost 40 species of
grasses
 Economically most important is the infection
of rye (Secale cereale L.) which is a major
crop in Germany, Scandinavia, Poland, Russia
and Ukraine (Geiger et al. 2009)

14.  Cleviceps prasitise mostly in temperate
regions
 Tropical and sub-tropical regions

15.  Ergot five stroma
 Each Stroma hundred perithicial
cavities
 Each perithecium fifty aci
 Each ascus eight ascospores
5 x 100 x 50 x 8 =2,00,000
 Thus, two lac propagules per ergot

16.  Claviceps causes the poisioning by releasing
the alkaloids
 Alkaloids of Claviceps
 Ergometrine
 Ergotamine
 LSD (lysergic acid diethylamide)

17.  The effect of infection on the host can result
in yield reduction by as much as 80% of seeds
(Buchta & Cvak, 1999)
 In studies (Asghar et al. 2016), 185 wheat
samples were collected from different areas of
Pakistan
 Claviceps purpurea species was found to be
inevident in all tested wheat samples (Asghar et
al. 2016)
 In Europe and Asia, it causes huge economic loss

20.  Claviceps purpurea : molecular aspects of a
unique pathogenic lifestyle article (Tudzynski
& Scheffer 2004)
 600 monocot species effected by the
infection of Claviceps purpurea
 Including important crop plants such as rye,
wheat, barley, rice, corn, millet and oats

21. Tudzynski & Scheffer 2004

22.  Claviceps that consumed by mammals from
different way cause ergotism in humans
 Symptoms
1. Burning
2. Hallucination
3. Mycotoxicosis

23.  Agronomic Measures
 Crop rotation
 Time of pollen production
 Deep plowing buries sclerotia in the soil
 Control of wild and weedy grasses and cereal
volunteers
 Irrigation
 Post-harvest field burning
 Certified seed
 Fungicides
 Mechanical Cleaning

24.  Claviceps economically very important to
produced alkaloids
 People should aware of Claviceps
 Need to control because it cause huge loss

25.  Webster, J., & Weber, R. (2007). Introduction to fungi.
Cambridge university press.
 Ainsworth, G. C. (2008). Ainsworth & Bisby's dictionary of the
fungi. Cabi.
 Desalegn, A., Abate, D., & Teshome, B. (2022). Awareness of
people living in Sagure District, Arsi, Ethiopia about ergot
fungus (Claviceps purpurea) and ergotism. SINET: Ethiopian
Journal of Science, 45(2), 165-173.
 Tudzynski, P., & Scheffer, J. A. N. (2004). Claviceps purpurea:
molecular aspects of a unique pathogenic lifestyle. Molecular
Plant Pathology, 5(5), 377-388.
 Hulvová, H., Galuszka, P., Frébortová, J., & Frébort, I.
(2013). Parasitic fungus Claviceps as a source for
biotechnological production of ergot alkaloids. Biotechnology
Advances, 31(1), 79-89.

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