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A brief survey of the literature published in the proceedings of the International Wheat Genetics Symposia (I through VII), as well as later issues of the journal GENOME, indicate that the choice of terminology is left to the authors. However, it seems that over time, some conventions were standardized.
These are the designation of:

xi) nullisomic lines with an "N" followed by the designated chromosome and genome,
xii) monosomic lines with an "M" followed by the designated chromosome and genome,
xiii) the disomic condition with a "D" followed by the designated chromosome and genome,
xiv) the trisomic condition with "Tri" followed by the designated chromosome and genome,
xv) tetrasomic lines with a "T" followed by the designated chromosome and genome. A "T" is also the designator for translocation lines to be consistent with current literature,
xvi) nullisomic-tetrasomic lines with an "N" followed by the number and genome of the nullisomic chromosome and a "T" followed by the same for the tetrasomic chromosome, as in N1A T1B,
xvii) monosomic and disomic additions by "MA" and "DA", respectively, and
xviii) monosomic and disomic substitutions as "MS" and "DS", respectively, followed by chromosome designation as indicated in rule vi, and
xix) abbreviations for wheat cultivars according to "Wheat Cultivar Abbreviations" 1985, Special Report 749, Agricultural Experiment Station, Oregon State University, Corvallis. This publication is currently under revision by CIMMYT.

Rules of hierarchy, established to ensure consistency in the naming of stocks, include that:

xx) the short arm is listed before the long arm,
xxi) the monosomic condition (either for the whole chromosome, chromosome arms, or parts thereof) is listed before the disomic condition except in cases where it is superceeded by rule xxii,
xxii) telosomic chromosomes are listed before isosomic chromosomes,
xxiii) in translocation chromosomes, the common wheat chromosome regardless of arm, is listed before the alien chromosome segment, and
xxiv) in translocation chromosomes between two alien chromosomes where the breakpoint is unknown, the order is according to homoeologous group.

Some stocks require abbreviations or symbols that were previously neither required nor based on the guidelines presented here. These include:

xxv) "Mt" and "Dt" indicate monotelo- and ditelosomic lines following rules i (for telochromosomes), xii, and xiii,
xxvi) the doubled condition is indicated with a "d" followed by the designated chromosome and genome, and
xxvii) the number sign "#" is used to distinguish different chromosomes belonging to the same homoeologous group of chromosomes within accessions, between accessions of the same nondomesticated species, or between homologous chromosomes within a cultivar.

Finally, certain symbols for use in computer databases, where some text styles am not available, include that:

xxviii) the symbol " ^ " encloses characters to be superacripted, and
xxix) the symbol " ` " encloses characters to be subscripted.

The following is a list of each aneuploid type or genetic stock, with an example of how the data would be displayed in each of the GrainGenes model fields for germplasm. For simplicity, chromosome 1A of wheat is used along with a homoeologue in rye (Secale cereale) or Triticum longissimum where needed. All of the chromosome stocks are represented to appear in the cultivar "Chinese Spring", hereafter designated by the abbreviation CS. The first column lists the variable name from the GrainGenes germplasm model (see Appendix I for a list of all variables available in this model). The second column lists the actual data that will appear in the database next to the variable name. Chromosome configuration is included with respect to item iii above Finally, a comment is included where required.

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