Several studies have indicated a noncorrespondence between genetic and physical distances in wheat chromosomes. To study the physical distribution of recombination, polymorphism for C-banding patterns was used to monitor recombination in 67 segments in 11 B-genome chromosome arms of Triticum turgidum. Recombination was absent in proximal regions of all chromosome arms; its frequency increased exponentially with distance from the centromere. A significant difference was observed between the distribution of recombination in physically short and physically long arms. In physically short arms, recombination was almost exclusively concentrated in distal segments and only those regions were represented in their genetic maps. In physically long arms, while a majority of the genetic distance was again based upon recombination in distal chromosome segments, some interstitial recombination was observed. Consequently, these regions also contributed to the genetic maps. Such a pattern of recombination, skewed toward terminal segments of chromosomes, is probably a result of telomeric pairing initiation and strong positive chiasma interference. Interference averaged 0.81 in 35 pairs of adjacent segments and 0.57 across the entire recombining portions of chromosome arms. The total genetic map lengths of the arms corresponded closely to those expected on the basis of their metaphase-I chiasma frequencies. As a consequence of this uneven distribution of recombination there can be a 153-fold difference (or more) in the number of DNA base pairs per unit (centiMorgan) of genetic length.
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Curtis CA, Lukaszewski AJ (1991) Genetic linkage between C-bands and storage protein genes in chromosome 1B of tetraploid wheat. Theor Appl Genet 81:245–252
Curtis CA, Lukaszewski AJ, Chrzastek M (1991) Metaphase-I pairing of deficient chromosomes and genetic mapping of deficiency breakpoints in wheat. Genome 34:553–560
Dvorak J, Appels R (1986) Investigation of homologous crossing-over and sister chromatid exchange in the wheat NorB2 locus coding for rRNA and the GliB2 locus coding for gliadins. Genetics 113:1037–1056
Dvorak J, Chen K-C (1984) Distribution of nonstructural variation between wheat cultivars along chromosome 6Bp: evidence from the linkage map and the physical map of the arm. Genetics 106:325–333
Dvorak J, Chen K-C, Giorgi B (1984) The C-band pattern of a Ph − mutant of durum wheat. Can J Gen Cytol 26:360–363
Flavell RB, Bennett MD, Seal AG, Hutchinson J (1987) Chromosome structure and organization. In: Lupton FGH (ed) Wheat breeding. Its scientific basis. Chapman and Hall, London, pp 211–268
Gale MD, Chao S, Sharp PJ (1990) RFLP mapping in wheat — progress and problems. In: Gustafson JP (ed) Gene manipulation in plant improvement II. Plenum Press, New York, pp 353–363
Gill KS, Lubbers EL, Gill BS, Raupp WJ, Cox TS (1991) A genetic linkage map of Triticum tauschii (DD) and its relationship to the D genome of bread wheat (AABBDD). Genome 34:362–374
Holm PB (1986) Chromosome pairing and chiasma formation in allohexaploid wheat, Triticum aestivum, analyzed by spreading of meiotic nuclei. Carlsberg Res Commun 51:239–294
Jampates R, Dvorak J (1986) Location of the Ph1 locus in the metaphase chromosome map and the linkage map of the 5Bq arm of wheat. Can J Genet Cytol 28:511–519
Kosambi DD (1944) The estimation of map distances from recombination values. Ann Eugen 12:172–175
Linde-Laursen I (1982) Linkage map of the long arm of barley chromosome 3 using C-bands and marker genes. Heredity 49:27–35
Lukaszewski AJ (1992) A comparison of physical distribution of recombination in chromosome 1R in diploid rye and in hexaploid triticale. Theor Appl Genet 83:1048–1053
McIntosh RA (1988) Catalogue of gene symbols for wheat. In: Miller TE, Koebner RMD (eds) Proc 7th Int Wheat Genet Symp, Institute of Plant Science Research, Cambridge UK, pp 1225–1323
Payne PI, Holt LM, Worland AJ, Law CN (1982) Structural and genetical studies on the high-molecular weight subunits of wheat glutenin III. Telocentric mapping of the subunit genes on the long arms of the homoeologous group 1 chromosomes. Theor Appl Genet 63:129–138
Sallee PJ and Kimber G (1978) An analysis of the pairing of wheat telocentric chromosomes. In: Ramanujam S (ed) Proc 5th Int Wheat Genet Symp, Indian Society of Genetics and Plant Breeding, New Delhi, India, pp 408–419
Sears ER (1972) Reduced proximal crossing-over in telocentric chromosomes of wheat. Genet Iber 24:233–239
Sears ER (1984) Mutations in wheat that raise the level of meiotic chromosome pairing. In: Gustafson JP (ed) Gene manipulation in plant improvement, 16th Stadler Genetics Symposium. Plenum Press, New York, pp 295–300
Snape JW, Flavell RB, O'Dell M, Hughes WG, Payne PI (1985) Intrachromosomal mapping of the nucleolar organizer region relative to three marker loci on chromosome 1B of wheat (Triticum aestivum) Theor Appl Genet 69:263–270
Sybenga J (1972) General cytogenetics. Elsevier, New York
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Lukaszewski, A.J., Curtis, C.A. Physical distribution of recombination in B-genome chromosomes of tetraploid wheat. Theoret. Appl. Genetics 86, 121–127 (1993). https://doi.org/10.1007/BF00223816
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