Intraspecific variations edit

 
Sclerotium of Claviceps purpurea onAlopecurus myosuroides

Early, scientists have observed Claviceps purpurea on other Poaceae as Secale cereale. 1855, Grandclement[1] described ergot on Triticum aestivum. During more than a century scientists aimed to describe specialized species or specialized varieties inside the species Claviceps purpurea. That's how are created the species

  • Claviceps microcephala Tul. (1853)
  • Claviceps wilsonii Cooke (1884)

Later scientists tried to detemine host varieties as

  • Claviceps purpurea var. agropyri
  • Claviceps purpurea var. purpurea
  • Claviceps purpurea var. spartinae
  • Claviceps purpurea var.wilsonii.

But molecular biology hasn't confirmed this hypothesis but has distinguished three groups differing in their ecological specificity.

  • G1 — land grasses of open meadows and fields;
  • G2 — grasses from moist, forest, and mountain habitats;
  • G3 (C. purpurea var. spartinae) — salt marsh grasses (Spartina, Distichlis).

The criteria to distinguish different groups was the morphology: The shape and the size isn't a good indicator because they strongly depends on the size and shape of the host floret. The size of conidia can be an indication but it is weak and it is is necessary to pay attention to that, due to osmotic pressure, it varies significantly if the spores are observed in honeydew and or in water. The density can be used indeed the group G3 is adapted to float in salt water.

The compounds of alkaloids is also used to differentiate the strains.

Host range edit

Pooideae edit

Agrostis canina, Alopecurus myosuroides , Bromus arvensis, Bromus hordeaceus, Bromus inermis [2] , Bromus marginatus, Elymus tsukushiense, Festuca arundinacea [3], Elytrigia repens.

Arundinoideae edit

Stipa, Danthonia, Molinia caerulea.

Chloridoideae edit

Spartina, Distichlis

Panicoideae edit

Setaria

Speculations edit

In 1951 at Pont St. Esprit in France a poisoning case occurred due to bread. [4]

References edit

  1. ^ Mr Gonod d'Artemare (1860). "Note sur l'ergot du froment". Bulletin de la société botanique de France: 771.
  2. ^ Eken C., Pažoutová S., Honzátko A., Yildiz S. (2006). "First report of Alopecurus arundinaceus, A. myosuroides, Hordeum violaceum and Phleum pratense as hosts of Claviceps purpurea population G2 in Turkey". J. Plant Pathol. 88: 121.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. ^ Douhan G. W., Smith M. E., Huyrn, K. L., Yildiz S. (2008). "Multigene analysis suggests ecological speciation in the fungal pathogen Claviceps purpurea". Molecular Ecology. 17 (9): 2276–2286. doi:10.1111/j.1365-294X.2008.03753.x. PMC 2443689. PMID 18373531.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. ^ Gabbai, J., Lisbonne, L. and Pourquier, F. (september 1951). "Multigene analysis suggests ecological speciation in the fungal pathogen Claviceps purpurea". Br Med J. 15: 2276–2286. {{cite journal}}: Check date values in: |date= (help)CS1 maint: date and year (link) CS1 maint: multiple names: authors list (link) PDF