Genetic analysis of two genes for vernalization response, the former Vrn2 and Vm4, by using PGR based molecular markers.

摘要

For genetical analysis of genes for vernalization response in wheat, formerly designated as Vrn2, molecular markers closely linked to the Vrn-1 gene family were analyzed by using NILs of "Triple Dirk". At Xwg644-5B, SNP (C/T) was detected between TD(B) carrying Vrn2 and TD(C) carrying vrn2, and dCAPS was successfully detected between two NILs. The analysis of a BF_2 population (TD(B)//TD(C) revealed close linkage (1.7 cM) between WG644-5B and Vrn2. Close linkage between Vrn2 and a SSR locus Xgwm408 was also confirmed (2.5cM). It was therefore concluded that the former Vrn2 is located on chromosome 5B and equivalent to Vrn-Bl. For Vrn4, it was located on 5D by monosomic analysis, and thus SSR markers mapped on chromosome 5D was analyzed, and close linkage (4.5cM) was detected between Vrn4 and a SSR locus Xgdm3. It was therefore concluded that Vrn4 is located on the proximal part of SDL and independent of Vrn-Dl located on the distal part of 5DL. Since no genes or QTLs controlling vernalization response have so far been reported in this region of homoeologous chromosome 5, it can be considered as a new class of vernalization gene which should be designated as Vrn-D5.