Plots of linkage disequilibrium as measured with the commonly used statistic (r 2 ) (y axis), which is based on the allele frequencies at two loci as a function of distance in kilobases (kb) (x axis) for the (A) cultivated, (B) landrace, and (C) wild samples (Caldwell et al., 2006).

Plots of linkage disequilibrium as measured with the commonly used statistic (r 2 ) (y axis), which is based on the allele frequencies at two loci as a function of distance in kilobases (kb) (x axis) for the (A) cultivated, (B) landrace, and (C) wild samples (Caldwell et al., 2006).

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Modern agriculture and conventional breeding and the liberal use of high inputs has resulted in the loss of genetic diversity and the stagnation of yields in cereals in less favourable areas. Increasingly landraces are being replaced by modern cultivars which are less resilient to pests, diseases and abiotic stresses and thereby losing a valuable s...

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... (Caldwell et al., 2006). High levels of association were found to stretch across the whole region in the cultivated sample, with linkage disequilibrium values extended across the en- tire 212-kb region. In contrast, linkage disequilibrium and its significance decreased as a function of increasing distance in both landraces and wild barley (Fig. 1). These contrasting pat- terns exist despite similar levels of inbreeding and most likely reflect different population histories associated with the oc- currence of bottlenecks and selection within the domesticated germplasm. Therefore, large linkage disequilibrium regions in cultivated, low-resolution whole-genome scans could be de- ...
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... can grow in desert condition (Nevo, 1992;Zohary and Hopf, 1998). Such ecotypes were identified in desert locations in Jor- dan (Jaradat et al., 1996). The study of drought stress on yield in Mediterranean environments noted above ( Comadran et al., 2007) identified genomic regions in landraces that may be very valuable for combating such stress. ...

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