Ergot Fungus (Claviceps Purpurea), Ergot Alkaloids and Ergotism in the Central Highlands of Arsi, Ethiopia
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Date
12/3/2017
Authors
Desalegn Asnake
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Publisher
Addis Ababa University
Abstract
Ergot fungi, Claviceps species, parasitize several monocot plants and produce a hardened dark to
dark-purple structure called the sclerotia. In Ethiopia, the ergot fungus infects only the wild oat
plant (Avena abyssinica) which is endemic to Ethiopia and Yemen. Ergot alkaloids produced in the
sclerotia of the ergot fungus, were responsible for mass poisoning in various areas of the world,
with the most recent report of mass poisoning in Arsi, Ethiopia. This study was initiated with the
objectives of identifying the ergot fungus (Claviceps purpurea) based on morphological and
molecular characteristics, ergot alkaloids, and assessing the knowledge of study participants about
ergot fungus and ergotism from the previously reported outbreaks areas of Arsi, Ethiopia.
Dimensions of the sexual and asexual structures were studied and statistically significant
differences (n = 30, P < 0.001) in the length and width of sclerotia collected from the study sites
Kechema Murkicha, Bucho Selassie and Shaldo Jigessa were observed. Dimensions of sclerotia
collected from all the study sites significantly differed (p < 0.001) from the dimensions of wild oats
seeds (n = 30). But, statistically significant differences were not observed (p > 0.05) for the
dimensions of conidia of ergot fungi collected from different study sites. Growth (100%) of the
sexual stage occurred only on Petri dishes incubated for 21 days at 5 OC followed by incubation at
25 OC. No growth was observed on the Petri dishes incubated under other temperature treatments.
The mean length of stromata ranged from 18.5 mm to 19mm and the mean diameter of capitula
ranged from 1.8 mm to 2mm. Cylindrical to flask shaped perithecia with mean length and width of
158.8 ± 3.7 μm and 89.2 ± 1.7 μm, and filiform shaped ascospores with mean length and width of
77.1 ± 3.7 μm and 3.3 ± 0.5 μm respectively were observed.
Phylogenetic analysis of the β-tubulin intron 3 region using maximum parsimony placed our
isolates in a separate cluster with strong bootstrap value of 94. Qualitative studies of the ergot
alkaloids using UPLC-QTOF High Definition Mass Spectrometery revealed the presence of
ergometrine, ergocryptine, ergocornine, ergosine, ergovaline, lysergyl alanine, lysergyl valine,
valine methyl ester, their respective -innine isomers and an ergopeptam (ergocryptam). A crosssectional
study conducted to assess the awareness of study participants recruited from Tijo, Digelu
and Kechema areas, Arsi, Ethiopia, showed lack of awareness about the fungus and the disease it
causes. Among the study participants who were shown the coloured picture of ergot fungus,
majority 55 (32.7%) described its name as ‘Sinara Guracha’ which is synonymous with “Black wild
ii
oat”. A multiple logistic regression model fitted revealed statistically significant association of the
study sites with knowledge of ergot (p < 0.05). Finally, morphological and molecular characteristics
placed the ergot fungi in the current study under Claviceps purpurea. The presence of the Claviceps
purpurea in farmers’ field, detection of additional toxic ergot alkaloids and lack of awareness of the
study participants about the ergot fungus, Claviceps purpurea, are the potential risks for the
community.
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Keywords
Claviceps Purpurea, Ergot Alkaloids, Avena Abyssinica, UPLC-QTOF, HDMS