Report on the 2nd IWGS Taxonomy Workshop (3 August 1998)

Prepared by Laura A. Morrison

Issues associated with the taxonomic treatment and nomenclature of the wheats are largely unchanged in the five years since they were discussed in 1993 at the 1st IWGS Workshop. Problems noted by participants in the 1998 workshop included the following: (1) the large number of different classifications currently in use, (2) the lack of uniformity in the nomenclature of wheat species, (3) the failure of researchers to consistently follow a given classification, and (4) misunderstandings of species concepts which have caused serious errors in the selection of germplasm. Participants agreed that the confusing condition of wheat taxonomy is particularly difficult for newcomers to wheat research.

A suggestion for an official endorsement of a particular classification that wheat researchers should follow for Triticum and Aegilops was considered and rejected. The difficulty of reaching a consensus for endorsement was evident in the various classifications followed by participants and individuals not in attendance who commented on this issue by email. Participants agreed with Mary Barkworth (Utah State University), a Triticeae taxonomist, who argued strongly against a workshop taxonomy endorsement. While the need for a monographic revision of the wheats was noted, the discussion at this point focused on a "good system of synonymy" as the most immediate need of wheat researchers and genetic resource managers. Jan Dvorak and Pat McGuire (University of California-Davis) recommended that a workshop committee be set up to organize a system of Synonymy Tables of wheat classifications.

John Raupp of the Wheat Genetic Resources Center (WGRC) at Kansas State University offered his assistance in this effort, suggesting that the tables of the recent van Slageren wheat classifications on the WGRC web site be used as a starting point for the proposed project. A volunteer committee was formed: John Raupp, Kansas State University; Laura Morrison, Oregon State University; Jan Dvorak, University of California, Davis; Giles Waines, University California, Riverside; and Mary Barkworth, Utah State University. Details for a working project were formulated in post-workshop discussions among these committee members and Dave Matthews and Gerry Lazo of the USDA GrainGenes database.

The following project description, briefly presented in the closing IWGS business meeting, sets out the design and goals of the Synonymy Tables Database System. It also is posted on the GrainGenes web site at http://wheat.pw.usda.gov:8000/cgi-bin/mboard/graintax/list.cgi.

  1. The Synonymy Tables database will have three components that will enable users to associate names with synonyms and names with classifications:
  1. A table listing the species names with authorities (and where relevant, lower ranking taxa at subspecific and botanical varietal levels) will be constructed for each of the 12 principal classifications currently in use. For Triticum: van Slageren (1994), Kimber & Sears/Kimber & Feldman (1987), Flora of Turkey (1985), Löve (1984), Dorofeev & Migushova (1979), Mac Key (1975). For Aegilops and Amblyopyrum: van Slageren (1994), Flora of Turkey (1985), Witcombe (1983), Hammer (1980), Kihara (1954), Eig (1929). See below for citations to these classifications.
  2. Each taxon name in a classification table will link to its synonyms. For example, in the table for the van Slageren classification, the diploid D-genome species Ae. Tauschii Coss. Will link to its synonyms--Ae. Squarrosa L., T. tauschii (Coss.) Schmal., T. aegilops P. Beauv. Ex Roem. & Schult., Patropyrum tauschii (Coss.) Löve.
  3. Each synonym will link to its associated classification (s). Following the above example with Ae. Tauschii, its four synonyms will link to their respective classifications--Ae. Squarrosa L. [name in the Eig, Kihara, and Witcombe classifications], T. tauschii (Coss.) Schmal. [name in the Kimber & Sears/Kimber & Feldman classification], T. aegilops P. Beauv. ex Roem. & Schult. [correct name with priority in Triticum sensu lato], Patropyrum tauschii (Coss.) Löve [Löve, 1984].

Each name also will link to itself when treated with the same name in other classifications. For example, Ae. Tauschii Coss. In the van Slageren classification table will link to Ae. Tauschii Coss. In the tables for the Hammer and Flora of Turkey classifications.

  1. Project coordinators include: Synonymy Table construction--Laura Morrison (Oregon State University) and John Raupp (Kansas State University); GrainGenes database implementation--Dave Matthews and Gerry Lazo (USDA-ARS); Triticeae taxonomy liaison--Mary Barkworth (Utah State University); wheat genetics liaisons--Giles Waines (University California-Riverside) and Jan Dvorak (University of California-Davis).
  2. Notices of the progress and eventual availability of the Synonymy Tables database will appear in the Wheat Information Service (published January and June) and the Annual Wheat Newsletter (published June).
  3. GrainTax, an internet bulletin board and mailgroup, has been set up as a discussion forum and an information exchange service for issues associated with wheat taxonomy. Notices published in the Wheat Information Service and the Annual Wheat Newsletter also will be posted here.
  4. To join the GrainTax mailgroup, contact Dave Matthews, matthews@greengenes.cit.cornell.edu. The bulletin board can be reached at http://wheat.pw.usda.gov:8000/cgi-bin/mboard/graintax/list.cgi.
  5. Recipients of this notice are encouraged to pass it on to their fellow wheat researchers.

 

References for the 12 taxonomic classifications in the Synonymy Tables database are as follows:

Davis, P.H. (ed.). 1985. Flora of Turkey and the East Aegean Islands. 9:232-255.

Dorofeev, V.F. and Migushova, E.F. 1979. Wheat. Vol. 1 (346 pp.) in V.F. Dorofeev and O.N. Korovina (eds.), Flora of Cultivated Plants. Leningrad [St. Petersburg]: Kolos. [in Russian].

Eig, A. Monographisch-kritische Übersicht der Gattung Aegilops. Feddes Repert. Spec. nov. reg. veg. Beih. 55: 1-228.

Hammer, K. 1980. Vorarbeiten zur monograhischen Darstellung von Wildpflanzensortimenten: Aegilops L. Kulturpflanze 28:33-180 [in German].

Kihara, H. 1954. Considerations on the evolution and distribution of Aegilops species based on the analyser-method. Cytologia 19:336-319.

Kimber, G. and Feldman, M. 1987. Wild wheat: an introduction. Spec. Rpt. 353. Coll. Agri. Univ. Mo. Columbia.

Kimber, G. and Sears, E.R. 1987. Evolution in the genus Triticum and the origin of cultivated wheat. Pp. 154-164 in: Heyne, E.G. (ed.), Wheat and wheat improvement, ed. 2 Madison.

Löve, Á. 1984. Conspectus of the Triticeae. Feddes Repert. 95:425-521.

Mac Key, J. 1975. The boundaries and subdivision of the genus Triticum. Proc. 12th Int. Bot. Congr. Leningrad [St. Petersburg].

Slageren, M.W. van. 1994. Wild wheats: a monograph of Aegilops L. and Amblyopyrum (Jaub. & Spach) Eig. Wageningen Agric. Univ. Pap. 1994 (7).

Witcombe, J.R. 1983. A guide to the species of Aegilops L.: their taxonomy, morphology and distribution. IBPGR [IPGRI], Rome.