AUTHOR=Zhang Xiangfen , Gao Manxia , Wang Shasha , Chen Feng , Cui Dangqun 

TITLE=Allelic variation at the vernalization and photoperiod sensitivity loci in Chinese winter wheat cultivars (Triticum aestivum L.)

JOURNAL=Frontiers in Plant Science

VOLUME=6

YEAR=2015

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2015.00470

DOI=10.3389/fpls.2015.00470

ISSN=1664-462X

ABSTRACT=<p>A total of 205 wheat cultivars from the Yellow and Huai valley of China were used to identify allelic variations of vernalization and photoperiod response genes, as well as the copy number variations (CNVs) of <italic>Ppd-B1</italic> and <italic>Vrn-A1</italic> genes. A novel <italic>Vrn-D1</italic> allele with 174-bp insertion in the promoter region of the recessive allele <italic>vrn-D1</italic> was discovered in three Chinese wheat cultivars and designated as <italic>Vrn-D1c</italic>. Quantitative real-time polymerase chain reaction showed that cultivars with the <italic>Vrn-D1c</italic> allele exhibited significantly higher expression of the <italic>Vrn-D1</italic> gene than that in cultivars with the recessive allele <italic>vrn-D1</italic>, indicating that the 174-bp insertion of <italic>Vrn-D1c</italic> contributed to the increase in <italic>Vrn-D1</italic> gene expression and caused early heading and flowering. The five new <italic>cis</italic>-elements (Box II-like, 3-AF1 binding site, TC-rich repeats, Box-W1 and CAT-box) in the 174-bp insertion possibly promoted the basal activity level of <italic>Vrn-D1</italic> gene. Two new polymorphism combinations of photoperiod genes were identified and designated as <italic>Ppd-D1_Hapl-IX</italic> and <italic>Ppd-D1_Hapl-X</italic>. Association of the CNV of <italic>Ppd-B1</italic> gene with the heading and flowering days showed that the cultivars with <italic>Ppd-B1_Hapl-VI</italic> demonstrated the earliest heading and flowering times, and those with <italic>Ppd-B1_Hapl-IV</italic> presented the latest heading and flowering times in three cropping seasons. Distribution of the vernalization and photoperiod response genes indicated that all recessive alleles at the four vernalization response loci, <italic>Ppd-B1_Hapl-I</italic> at <italic>Ppd-B1</italic> locus, and <italic>Ppd-D1_Hapl-I</italic> at the <italic>Ppd-D1</italic> locus were predominant in Chinese winter wheat cultivars. This study can provide useful information for wheat breeding programs to screen wheat cultivars with relatively superior adaptability and maturity.</p>