Mapping QTL for Phenological and Grain-Related Traits in a Mapping Population Derived from High-Zinc-Biofortified Wheat

Abstract

Genomic regions governing days to heading (DH), days to maturity (DM), plant height (PH), thousand-kernel weight (TKW), and test weight (TW) were investigated in a set of 190 RILs derived from a cross between a widely cultivated wheat-variety, Kachu (DPW-621-50), and a high-zinc variety, Zinc-Shakti. The RIL population was genotyped using 909 DArTseq markers and phenotyped in three environments. The constructed genetic map had a total genetic length of 4665 cM, with an average marker density of 5.13 cM. A total of thirty-seven novel quantitative trait loci (QTL), including twelve for PH, six for DH, five for DM, eight for TKW and six for TW were identified. A set of 20 stable QTLs associated with the expression of DH, DM, PH, TKW, and TW were identified in two or more environments. Three novel pleiotropic genomic-regions harboring co-localized QTLs governing two or more traits were also identified. In silico analysis revealed that the DArTseq markers were located on important putative candidate genes such as MLO-like protein, Phytochrome, Zinc finger and RING-type, Cytochrome P450 and pentatricopeptide repeat, involved in the regulation of pollen maturity, the photoperiodic modulation of flowering-time, abiotic-stress tolerance, grain-filling duration, thousand-kernel weight, seed morphology, and plant growth and development. The identified novel QTLs, particularly stable and co-localized QTLs, will be validated to estimate their effects in different genetic backgrounds for subsequent use in marker-assisted selection (MAS).

Genome-Wide Association Study for Grain Protein, Thousand Kernel Weight, and Normalized Difference Vegetation Index in Bread Wheat (Triticum aestivum L.)

“…The pattern of subgenome-wise marker distribution is also similar, as maximum markers were located on subgenome B, and an approximately similar number of markers were mapped on A and D subgenomes. In earlier studies also, a similar pattern of QTL and marker distribution among the subgenomes for grain-quality traits was reported [ 21 , 26 ]. Krishnappa et al [ 22 ] studied a RIL population wherein none of the QTL was identified on the D subgenome due to a very less distribution of markers; however, the enrichment of the D genome with additional SNP markers in the same mapping population has significantly increased the power of QTL identification.…”

“…The conventional approach of QTL mapping depends on the genetic composition of bi-parental populations. A large number of QTLs have been identified in the last decade in wheat for the expression of GPC [ 21 , 22 , 23 , 24 , 25 ], TKW [ 26 , 27 , 28 , 29 ], and NDVI [ 30 , 31 , 32 ] through bi-parental-based conventional QTL mapping approach. However, the mapping resolution is very low in bi-parental population-based QTLs due to limited crossovers.…”

GWAS in a Collection of Bulgarian Old and Modern Bread Wheat Accessions Uncovers Novel Genomic Loci for Grain Protein Content and Thousand Kernel Weight

“…The observed moderate to high values of broad-sense heritability and the consistency of trait records evidenced by the significant correlations between the crop seasons suggest that a considerable part of the variation is due to inherent genetic differences among the accessions. These results agree with similar findings in bread and durum wheat for GPC [ 19 , 25 , 27 , 40 ], and TKW [ 13 , 41 ]. Given that the panel contains historical and contemporary varieties released or collected between 1925 and 2010, it is possible that the recorded genetic variance—especially for TKW—is inflated.…”

Investigating the Genetic Contribution of Effective Traits in Grain Yield of Durum Wheat under the Normal Irrigation and Drought Stress Conditions at the Terminal Drought

“…Lines 15, 38 and 2 have had the most averages of production index. In addition to these three lines, lines 43,8,49,16,34,50,11,20,10,57,59 and 39 had more production averages as compared to the parent Shotordandan. Regarding stress tolerance index (STI), lines 15, 38, 2 and 8 were of the most amount.…”