Genetic analysis of yield and heat stress related traits in wheat (Triticum aestivum L. em. Thell) using microsatellite markers

Abstract

Microsatellite markers were used for genetic analysis of terminal heat tolerance in F 2 (PBW373 × WH1081) population of wheat (Triticum aestivum L. em. Thell). Two parents were evaluated in field under normal sown and late sown conditions. For genotyping DNA from both parents PBW373 and WH1081 was amplified using 200 SSRs. Only 22 SSRs produced polymorphic bands, of size between 100 to 300 bp and an average of 1.45 alleles. The single marker analysis identified 19 markers indicating the putative QTLs for yield, its components and heat stress related physiological traits. The number of markers on these 16 linkage groups varied from one to four. On A genome 13 QTLs on B genome 5 QTLs and on D genome 9 QTLs were identified, respectively. The A, B and D genomes had 1360.3 cM, 272.4 cM and 919.5 cM of linkage coverage with average interval distances of 104.63 cM, 54.48 cM and 102.16 cM/Marker. A total of nine QTLs were resolved following composite interval mapping, one QTL was detected at a LOD score equal to threshold value of 2.5 while eight at LOD scores above the threshold value. All the nine QTLs were shown to be on definitive location on chromosome 3A (QDh.CCSHAU-3A, QDa.CCSHAU-3A and QPm.CCSHAU-3A), chromosome (QBm.CCSHAU-5A, QCtd.CCSHAU-5A and QCl.fl.CCSHAU-5A), chromosome6A (QPh.CCSHAU-6A) and chromosome3B (QTgw.CCSHAU and QMts.CCSHAU-3B). Use of these markers save times, resources and energy that are needed not only for raising large segregating populations for sveral generations, but also for estimating the parameters used for selection.

Mapping QTLs for physiological and biochemical traits related to grain yield under control and terminal heat stress conditions in bread wheat (Triticum aestivum L.)

“…For CMS, QTLs were found on chromosomes 2B, 3B and 7A in the heat stress condition. Previous studies also showed that QTLs for CMS were located on chromosomes 1D, 2B, 3B and 7A (Talukder et al 2014;Gupta et al 2015). However, although most of the genomic regions identified in this study have been reported previously, new QTLs were also identified for different traits.…”

Genome-wide association mapping in bread wheat subjected to independent and combined high temperature and drought stress

“…Its advantage over the more conventional bi-parental mapping approach lies mainly in the greater extent of allelic variation which can be surveyed, while also avoiding the need to establish a customized mapping population [ 11 ]. Its ability to resolve marker/trait associations (MTAs) depends upon the extent of linkage disequilibrium (LD) present in the association panel [ 12 , 13 ]. An important factor influencing LD is the genetic relationship between entries, which can be readily inferred from genome-wide genotypic datasets [ 14 , 15 ].…”

“…Most of the AM analyses of bread wheat focusing on its stress response have to date treated drought stress separately from high temperature stress [ 12 , 26 – 29 ], although the two stress agents are known to interact [ 30 , 31 ]. The present objectives were to determine both the individual and combined effects of high temperature and drought stress on a range of yield traits in a panel of spring wheats, to characterize LD and to identify markers potentially associated with yield.…”

Association analysis for agronomic traits in wheat under terminal heat stress

“…Each significant MTA was identifiend on 1A , 6A and 2B for flag leaf area, spikelet per spike and biomass per plant respectively whereas, only two MTAs were identified on 1A and 7D under heat stress conditions. MTAs for different agronomic traits on 3A , 4A , 6A , 1B , 2B , 2D and 6D were previously reported normal conditions ( Sharma et al, 2021 , Seetharam et al, 2021 , Gupta et al, 2015 , Ain et al, 2015 , Zhao et al, 2015 ) that was different from markers identified and grwoing conditions in current study. In summary, few markers associated with traits were identified previously on same chromosomes under normal conditions, although heat stress conditions investigated in present study was different from previous studies.…”