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methods (including DNA studies) for verifying identi- ties and detecting genetic THE variability in Claviceps spe- , CLAVICEPS, of the pathogen, the alkaloid profile, physi- cies. ology and mode of infection, and some ON GRASSES: aspects pertaining to the epidemiology and Anyone encountering speci- ecology of the disease. mens of grasses or sedges infected with fungi that may A SPECIAL REQUEST FOR SPECIMENS Claviceps belong to this , is re- have traditionally quested to collect some seed been identified heads, dry the samples in a ELNA J. VAN DER LINDE

plant press or even in a according to mor- Mycology Unit, phological charac- (close-up) telephone directory, and post Biosystematics Division, teristics as well as them in clearly marked paper ARC-Plant Protection Research Institute the hosts from envelopes (not plastic) to the following address: which they were recorded. How- ever, morphologi- ELNA J. VAN DER LINDE cal features within species tend to be MYCOLOGY UNIT, variable, and de- BIOSYSTEMATICS DIVISION, ARC-PLANT PROTECTION RESEARCH scription of a new INSTITUTE Grass seed head, show- species based ing some seeds re- solely on the host Mycology Unit, placed with Claviceps National Collection of Fungi is inconclusive due microcephala ARC-Plant Protection Research Institute to the polygeneric P/Bag X134 host range of the majority of ergot fungi. Queenswood 0121 Attempts to circumvent the problem led to PRETORIA the establishment of varieties, special forms Phone: (012) 304-9568 or races, and host-specific groups. Other Fax: (012) 325-6998 means of distinguishing between species, E-mail: [email protected] such as alkaloid profiles and the ability to float on water, have also been utilized to identify chemo-races and habitat specializa- Grass seed heads showing some seeds replaced with Claviceps purpurea sclerotia tion. Important: In recent years, much emphasis has been placed on the application of molecular Please include all collection information, i.e: Locality of collection (farm, district, nearest town, etc.), date of collection, name of collector, name of host plant (scientific or common name, if known). FUNGI ON GRASSES: CLAVICEPS SPP. (ERGOT)

This is an earnest request to everyone February–May of each year, it is almost impos- due to various tetracyclic tox- in southern Africa who comes across a sible for one person to cover all areas in ins - collectively referred to as ergot grass or sedge with fungus-infected search of them. It would therefore be much alkaloids - contained in them. seed heads, to assist in a research study appreciated if botanists, farmers, entomolo- by collecting and sending specimens to gists, etc., would be on the look-out for these Consumption of ergot-infected fodder the address given at the end of this fungi and send speci- leads to ergotism, a toxicosis character- pamphlet. mens to the Na- ised by psychotic delusions, nervous tional Collection of spasms, convulsions, gangrene, abor- A PhD study on Claviceps of nut-sedge Fungi (address be- tion, infertility and reduction in milk was completed in 2005. Collection and low). production. Ergot poisoning continues submission of further specimens will to be of economic importance as an enable follow-up research studies. ‘Ergot’ refers to the animal disease, with These studies will result in various pub- infection of ovaries Nut-sedge seed head, with outbreaks regularly lications, as well as a better under- in the florets of ce- Claviceps cyperi exuding drop- being described in standing of several aspects, including reals and grasses lets of honeydew. swine, sheep, phylogenetic placement of South Afri- (Poaceae), sedges horses, poultry, and can and south- (Cyperaceae) and rushes (Juncaceae) by 47 de- particularly cattle. ern African scribed and various undescribed fungal species Mortalities are, how- species. of the ascomycete genus Claviceps ever, rare and after (, ). removal of the Because of the source of intoxica- vastness of A total of 509 species in the Poaceae, 17 in the tion, it takes about Dark, elongate sclerotia the country, Cyperaceae and 4 in the Juncaceae have been two months for milk of Claviceps digitariae on florets of Digitaria as well as the reported as hosts, although the actual number production to return (Smuts finger) fact that the of poaceous hosts is considerably higher. The to normal and the fungal survival Seed head of nut-sedge, showing disease destroys between 5 and 10 % of the symptoms to abate. ARC-Plant Protection Research Institute dark, elongate, curved scle- structures are rotium of Claviceps cyperi. seed in infected heads, but its main impor- only found / tance is the sclerotia (survival structures) The research on C. cyperi elucidated the are visible on grasses and sedges during which are poisonous to humans and animals morphology, and phylogeny