Detecting and identifying polymorphism of Viviparous-B1 gene and its seed dormancy in mini-core collection of Chinese wheat varieties.

A pair of primers based on wheat Viviparous(Vp1)-B1 sequence in GenBank was designed and used to detect allelic variations in mini-core collections of Chinese wheat(Triticum aestivum) varieties.Results indicated that four alleles were identified,named as Vp1-B1a,Vp1-B1b,Vp1-B1c and Vp1-B1e.The varieties with Vp1-B1a were detected to have higher germination index(GI,49.8%),and those varieties with Vp1-B1b,Vp1-B1c and Vp1-B1e alleles had lower GI,especially for Vp1-B1b,its GI was 18.9%.GI of those varieties with Vp1-B1c and Vp1-B1e alleles was 25.7% and 25.6%,respectively.The Vp1-B1e was proved to be a novel allele by the improved denaturing PAGE and sequence blast,and had higher identity with Vp1-B1c(99%).An insertion of 4-bp(ATAT) and two SNP were found in the third intron of Vp1-B1e compared with Vp1-B1c.