copy number variation affecting the photoperiod-b1 and vernalization-a1 genes is associated with altered flowering time in wheat (triticum aestivum)影响photoperiod-b1和vernalization-a1基因拷贝数变异与改变花期小麦(小麦).pdfVIP

Copy Number Variation Affecting the Photoperiod-B1 and Vernalization-A1 Genes Is Associated with Altered Flowering Time in Wheat (Triticum aestivum) ´ 1.¤ 1. 1. 2 1 Aurora Dıaz , Meluleki Zikhali , Adrian S. Turner , Peter Isaac , David A. Laurie * 1John Innes Centre, Norwich Research Park, Norwich, Norfolk, United Kingdom, 2 iDNA Genetics Ltd., The Norwich BioIncubator, Norwich Research Park, Norwich, United Kingdom Abstract The timing of flowering during the year is an important adaptive character affecting reproductive success in plants and is critical to crop yield. Flowering time has been extensively manipulated in crops such as wheat (Triticum aestivum L.) during domestication, and this enables them to grow productively in a wide range of environments. Several major genes controlling flowering time have been identified in wheat with mutant alleles having sequence changes such as insertions, deletions or point mutations. We investigated genetic variants in commercial varieties of wheat that regulate flowering by altering photoperiod response (Ppd-B1 alleles) or vernalization requirement (Vrn-A1 alleles) and for which no candidate mutation was found within the gene sequence. Genetic and genomic approaches showed that in both cases alleles conferring altered flowering time had an increased copy number of the gene and altered gene expression. Alleles with an increased copy number of Ppd-B1 confer an early flowering day neutral phenotype and have arisen independently at least twice. Plants with an increased copy number of Vrn-A1 have an increa