Frontiers in Plant Science (Oct 2023)

QTL mapping for kernel-related traits in a durum wheat x T. dicoccum segregating population

  • Ana Paola Valladares García,
  • Ana Paola Valladares García,
  • Francesca Desiderio,
  • Rosanna Simeone,
  • Stefano Ravaglia,
  • Roberto Ciorba,
  • Agostino Fricano,
  • Davide Guerra,
  • Antonio Blanco,
  • Luigi Cattivelli,
  • Elisabetta Mazzucotelli

DOI
https://doi.org/10.3389/fpls.2023.1253385
Journal volume & issue
Vol. 14

Abstract

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Durum wheat breeding relies on grain yield improvement to meet its upcoming demand while coping with climate change. Kernel size and shape are the determinants of thousand kernel weight (TKW), which is a key component of grain yield, and the understanding of the genetic control behind these traits supports the progress in yield potential. The present study aimed to dissect the genetic network responsible for kernel size components (length, width, perimeter, and area) and kernel shape traits (width-to-length ratio and formcoefficient) as well as their relationships with kernel weight, plant height, and heading date in durum wheat. Quantitative Trait Locus (QTL) mapping was performed on a segregating population of 110 recombinant inbred lines, derived from a cross between the domesticated emmer wheat accession MG5323 and the durum wheat cv. Latino, evaluated in four different environments. A total of 24 QTLs stable across environments were found and further grouped in nine clusters on chromosomes 2A, 2B, 3A, 3B, 4B, 6B, and 7A. Among them, a QTL cluster on chromosome 4B was associated with kernel size traits and TKW, where the parental MG5323 contributed the favorable alleles, highlighting its potential to improve durum wheat germplasm. The physical positions of the clusters, defined by the projection on the T. durum reference genome, overlapped with already known genes (i.e., BIG GRAIN PROTEIN 1 on chromosome 4B). These results might provide genome-based guidance for the efficient exploitation of emmer wheat diversity in wheat breeding, possibly through yield-related molecular markers.

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