Massive negative interference, and putative quasi-linkage upon hybridization of wild emmer wheat, triticum dicoccoides, with cultivated wheat, T. Durum
Material type:
TextPublication details: San Diego, CA (USA) Scherago International : 2001Subject(s): Summary: A genetic map of a cross between wild emmer. wheat. Triticum dicoccoides. and cultivated wheat. T. durum was constructed spanning more than 3000 cM (see companion. abstract). The main objeciive of this study was to characterize the recombination patterns upon crossing of T. dicoccoides with its domesticated descendant. T.dururm ( cultivar Langdon). Massive negative interference (an excess of double crossovers in adjacent intervals relative to the expected rate on the assumption of no interference) was observed in most of the chromosomes in both genomes. A and B. of our T. durum x T. dicoccoides hybrid. and confirmed also for chromosome 1B in another independent cross of different pareritallines. The general pattern of distribution of the island of negative interference included near-centromeric location. spanning the centromer and median/subterminal location. A departure from random segregation of markers on non-homologous chromosomes is termed quasi-linkage. This phenomenon was observed earlier both in plants and animals. especially in interspecific hybrids. In our F2 mapping population (T. durum x T. dicoccoides) several pairs of non-homologues chromosomes manifested a highly significant deviation of recombination of their markers from the expected r=50% level. These included either excess or deficit of recombinant genotypes. Following these results. we conducted a few other tests of quasi-linkage. with hexaploid wheat. maize. and Arabidopsis. It appeared that quasi-linkage might indeed be a significant phenomenon in wheat, as well as in other plants.
| Item type | Current library | Collection | Call number | Copy number | Status | Date due | Barcode | Item holds | |
|---|---|---|---|---|---|---|---|---|---|
| Conference proceedings | CIMMYT Knowledge Center: John Woolston Library | Reprints Collection | REP-9067 (Browse shelf(Opens below)) | 1 | Available | 629550 |
Abstract only
A genetic map of a cross between wild emmer. wheat. Triticum dicoccoides. and cultivated wheat. T. durum was constructed spanning more than 3000 cM (see companion. abstract). The main objeciive of this study was to characterize the recombination patterns upon crossing of T. dicoccoides with its domesticated descendant. T.dururm ( cultivar Langdon). Massive negative interference (an excess of double crossovers in adjacent intervals relative to the expected rate on the assumption of no interference) was observed in most of the chromosomes in both genomes. A and B. of our T. durum x T. dicoccoides hybrid. and confirmed also for chromosome 1B in another independent cross of different pareritallines. The general pattern of distribution of the island of negative interference included near-centromeric location. spanning the centromer and median/subterminal location. A departure from random segregation of markers on non-homologous chromosomes is termed quasi-linkage. This phenomenon was observed earlier both in plants and animals. especially in interspecific hybrids. In our F2 mapping population (T. durum x T. dicoccoides) several pairs of non-homologues chromosomes manifested a highly significant deviation of recombination of their markers from the expected r=50% level. These included either excess or deficit of recombinant genotypes. Following these results. we conducted a few other tests of quasi-linkage. with hexaploid wheat. maize. and Arabidopsis. It appeared that quasi-linkage might indeed be a significant phenomenon in wheat, as well as in other plants.
English
0108|AL-Wheat Program
Jose Juan Caballero
Reprints Collection
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