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laborious. It requires extensive and careful literature search to ensure that only valid
names (in agreement with the priority rule of the ICN) will be given to taxa.
However, once established, a single and conclusive taxonomic treatment that is
generally used would greatly simplify the understanding of researchers working on
Triticeae taxa. The same is true for the usage of the genomic symbols. Generally,
genome designations offer an effi cient and abbreviated way to depict relationships
between allopolyploids and their progenitors. For this reason, they are used in
nearly every study dealing with polyploids in Triticeae. Nonetheless, since Löve’s
( 1984 ) revision of the tribe, several suggestions have already been made to rename
some of the genomes (Table 1.1 ). Often, these suggestions have been followed by
only some scientists, which led to another level of confusion. Depending on the
publication at hand, it can be diffi cult to track back the change of a genome name
and the reasons for it.
With respect to the genus Triticum , fi rst, a consensus on its interpretation (in a
broad or narrow sense) is desirable. The separate generic status of Aegilops and
Triticum s.str. can be favored because of clear morphological distinctions and the
long tradition in keeping the taxa separate (Barkworth and von Bothmer 2009 ).
Additionally, there are taxonomists that suggest the general acceptance of paraphy-
letic taxa (e.g., Brummitt 2006 ), as this refl ects the course of evolutionary history.
The situation within Triticum s.str. is more complex, since two different taxonomic
treatments are adopted in different parts of the world. The treatment of Dorofeev
et al. ( 1979 ) is mainly used in Eastern countries, whereas Mac Key ( 1977 , 1989 ) or
the revision made by van Slageren ( 1994 ) are used in Western countries. Hence,
there is no long tradition for one or the other of the treatments. Although the two
main classifi catory systems consider genomic information, it is then partially inter-
preted in different ways (i.e., the grouping of species into subgenera depending on
the possession of the A b^ or A u^ genome by Dorofeev et al. ( 1979 ). Both treatments are
mainly based on different data and differ in the acceptance of the species rank for
“commercially” cultivated and artifi cial hybrid wheat. So far, there is no treatment
that suffi ciently incorporates molecular data. Finally, a taxonomic treatment for
Triticum (s.l. or s.str.) needs an open system offering a fl exible solution to cope with
new taxa that need to be included because of, for instance, success in breeding or the
retention of new spontaneous or induced mutations (e.g., van Slageren 1994 ). This
seems essential to establish a stable taxonomic treatment for the genus. Moreover, a
classifi catory system that refl ects the progenitors of a taxon already in its name is
both self-informative and easy to learn. To avoid loss of information related to bio-
diversity and genetic resources, morphological distinctions can be made under
lower taxonomic ranks, e.g., varieties in case of wild taxa. In case of species or
lower taxonomic rank brought into cultivation , a cultivar name can be given accord-
ing to the rules of the International Code of Nomenclature for Cultivated Plants
(ICNCP, Article 20; Brickell et al. 2009 ). The naming of hybrid taxa is also regu-
lated by the ICN (Appendix I; McNeill et al. 2012 ).
However, a future classifi catory system for Triticeae and/or Triticum can only
decrease current confusion in the taxonomy, if it experiences general attention and
acceptance by scientists working with these taxa. Therefore, one central database
N. Bernhardt