Physical Mapping of Ssr Markers in Bread Wheat: Physical Mapping in Wheat

Wheat one of the most important cereal crop, feeds about 40% of the global population. Due to the very large size of the genome, presence of three homoeologus groups with 80% repetitive DNA in the genome; makes any attempt of achieving success in wheat molecular mapping extremely challenging. Also, since recombination rates vary in different parts of the genome, there is a clear need to construct the physical maps, which can then be compared with genetic maps to make them useful for both marker assisted selection and map-based cloning. This study on bread wheat (Triticum aestivum L. em Thell.) was undertaken mainly to develop whole genome physical map of simple sequence repeats (SSRs; also described as microsatellites) including both, genomic-SSRs (gSSRs) and expressed sequence tag-SSRs (EST-SSRs). In this context, a total of 1508 SSRs were attempted for physical mapping; of these only 641 SSRs could be mapped to 1028 loci. The present study will certainly attract the attention of researchers, scientist and plant breeders working on wheat and other cereal crops particularly in areas of molecular mapping in wheat.