Abstract

Terminal heat stress causes irreversible damage to wheat crop productivity. It reduces the vegetative growth and flowering period that consequently declines the efficiency to capture available stem reserves (carbohydrates) in grains. Markers associated with thermotolerant traits ease in marker assisted selection (MAS) for crop improvement. It identifies the genomic regions associated with thermotolerant traits in wheat, but the scarcity of markers is the major hindrance in crop improvement. Therefore, 158 wheat genotypes were subjected to genotyping with 165 simple sequence repeat markers dispersed on three genomes (A, B and D). Allelic frequency and polymorphic information content values were highest on genome A (5.34 (14% greater than the lowest value at genome D) and 0.715 (3% greater than the lowest value at genome D)), chromosome 4 (5.40 (16% greater than the lowest value at chromosome 2) and 0.725 (5% greater than the lowest value at chromosome 6)) and marker xgwm44 (13.0 (84% greater than the lowest value at marker xbarc148) and 0.916 (46% greater than the lowest value at marker xbarc148)). Bayesian based population structure discriminated the wheat genotypes into seven groups based on genetic similarity indicating their ancestral origin and geographical ecotype. Linkage disequilibrium pat-tern had highest significant (P < 0.001) linked loci pairs 732 on genome A at r(2) > 0.1 whereas, 58 on gen-ome B at r(2) > 0.5. Linkage disequilibrium decay (P < 0.01 and r(2) > 0.1) had larger LD block (5-10 cM) on genome A. Highly significant MTAs (P < 0.000061) under heat stress conditions were identified for flag leaf area (xwmc336), spikelet per spike (xwmc553), grains per spike (cxfa2147, xwmc418 and xwmc121), biomass (xbarc7) and grain yield (xcfa2147 and xwmc671). The identified markers in this study could facil-itate in MAS and gene pyramiding against heat stress in wheat. (C) 2021 Published by Elsevier B.V. on behalf of King Saud University.

Keywords

Terminal heat stress; Wheat; Marker assisted selection; Gene pyramiding

Published in

Saudi Journal of Biological Sciences
2021, Volume: 28, number: 12, pages: 7404-7415
Publisher: ELSEVIER

SLU Authors

• Ahmed, Mukhtar

  • Arid Agriculture University
  • Department of Agricultural Research for Northern Sweden, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

End hunger, achieve food security and improved nutrition and promote sustainable agriculture


UKÄ Subject classification

Agricultural Science


Publication identifier

DOI: https://doi.org/10.1016/j.sjbs.2021.08.050

Permanent link to this page (URI)

https://res.slu.se/id/publ/114658