Identification of genetic factors controlling kernel hardness and related traits in a recombinant inbred population derived from a soft × ‘extra-soft’ wheat (Triticum aestivum L.) cross uri icon

abstract

  • Kernel hardness or texture, used to classifywheat (Triticum aestivum L.) into soft and hard classes, is amajor determinant of milling and baking quality. Wheatgenotypes in the soft class that are termed ?extra-soft? (withkernel hardness in the lower end of the spectrum) havebeen associated with superior end-use quality. In order tobetter understand the relationship between kernel hardness,milling yield, and various agronomic traits, we performed quantitative trait mapping using a recombinant inbred linepopulation derived from a cross between a common softwheat line and a genotype classified as an ?extra-soft? line.A total of 47 significant quantitative trait loci (QTL)(LOD C 3.0) were identified for nine traits with the numberof QTL affecting each trait ranging from three to nine.The percentage of phenotypic variance explained by theseQTL ranged from 3.7 to 50.3%. Six QTL associated withkernel hardness and break flour yield were detected onchromosomes 1BS, 4BS, 5BS, 2DS, 4DS, and 5DL. Thetwo most important QTL were mapped onto orthologousregions on chromosomes 4DS (Xbarc1118?Rht-D1) and4BS (Xwmc617?Rht-B1). These results indicated that the?extra-soft? characteristic was not controlled by the Hardness(Ha) locus on chromosome 5DS. QTL for eightagronomic traits occupied two genomic regions near semidwarfgenes Rht-D1 on chromosome 4DS and Rht-B1 onchromosome 4BS. The clustering of these QTL is eitherdue to the pleiotropic effects of single genes or tightlinkage of genes controlling these various traits

publication date

  • 2012
  • 2012