Microsatellite mapping of the gene for sham ramification in spikelets derived from a hexaploid wheat ( Triticum spp.) accession 171ACS

Plants with elongated spikelet rachilla (sham ramification) have been found in the progenies of a cross between hexaploid wheat ( Triticum aestivum L., 2n = 6x = 42, BBAADD genome) line ‘171ACS’ and durum wheat ( T. durum Desf., 2n = 4x = 28, BBAA genome) ‘Bereketli-95’. 171ACS was the carrier of the genes for sham ramification and extra glume. Expression of both of these traits was suppressed in hexaploid wheat. The gene for “sham ramification” ( shr 171ACS ) was mapped by genotyping F 2 populations using microsatellite markers. In the F 2 of 171ACS/Bereketli-95, the shr 171ACS gene was located in chromosome arm 5AL. The shr 171ACS gene and the gene for extra glume ( exg ) were completely linked. The shr 171ACS /exg gene complex was bracketed by the markers Xbarc319 and Xbarc232 on the long arm of chromosome 5A. In F 2 hybrids between #145 and #629, and T. durum ‘LD222’, the shr 171ACS gene was completely linked to the exg gene, and the shr 171ACS /exg gene complex was located in the long arm of chromosome 5A. F 2 hybrids between two tetraploid ramified progenies and T. jakubzineri Udacz. et Shakhm. (2n = 4x = 28, BBAA genome) indicated that shr 171ACS was allelic to shr1 .