SNP-based association analysis for seedling traits in durum wheat (<i>Triticum turgidum</i> L. <i>durum</i> (Desf.))

Abstract

In the present study, 150 accessions of worldwide originated durum wheat germplasm (Triticum turgidum spp. durum) were observed for major seedling traits and their growth. The accessions were evaluated for major seedling traits under controlled conditions of hydroponics at the 13th, 20th, 27th and 34th day-after germination. Biomass traits were measured at the 34th day-after germination. Correlation analysis was conducted among the seedling traits and three field traits at maturity, plant height, grain weight and 1000-grain weight observed in four consecutive years. Associations of the measured seedling traits and SNP markers were analyzed based on the mixed linear model (MLM). The results indicated that highly significant genetic variation and robust heritability were found for the seedling and field mature traits. In total, 259 significant associations were detected for all the traits and four growth stages. The phenotypic variation explained (R2) by a single SNP marker is higher than 10% for most (84%) of the significant SNP markers. Forty-six SNP markers associated with multiple traits, indicating non-neglectable pleiotropy in seedling stage. The associated SNP markers could be helpful for genetic analysis of seedling traits, and marker-assisted breeding of new wheat varieties with strong seedling vigor.

Detection of QTLs for seedling characteristics in barley (Hordeum vulgare L.) grown under hydroponic culture condition

“…Some studies indicated that MRL and MRN were one of the most desirable traits contributing to drought avoidance, and RDW was another important parameter for the roots associated with water use efficiency and long-term drought [ 46 , 47 ]. Recent studies have also confirmed that most of the seedling traits, such as leaf area (LA), seedling height (SH), seedling fresh weight (FW), seedling dry weight (DW), shoot dry weight (SDW) and root dry weight (RDW), were closely and positively correlated with yield component traits [ 48 ]. Previous genetic research on barley were focused mainly on the later stage; thus, the genetic mechanism underlying seedling characteristics is still lacking.…”

SNP-based association study of kernel architecture in a worldwide collection of durum wheat germplasm

“…In which, a stable and multi-traits associated locus BE500291_5_A_37 was mapped on chromosome 5A (Table 3 and S5 Fig), which can be further explored for discovering candidate genes and for function analysis across traits and environments. Integrated with our published studies [36,65,66], we further picked out all of those significant SNPs which we had previously found in chromosome 5A. In total, 23 unique significant SNPs were associated with 41 evaluated traits at different developmental stages of vegetative and reproductive growth in durum (S8 Table).…”

Association mapping of drought tolerance indices in wheat: QTL-rich regions on chromosome 4A

“…Moreover, Edae et al (2014) found that the chromosomes of spring wheat showed substantial differences in the proportion of marker pairs in significant linkage disequilibrium (LD) from the maximum 62 % for chromosome 4A to the minimum 20 % for chromosome 5A; an important aspect of association studies. Despite the extreme complexity of the wheat genome, the development of molecular marker technology has enabled the discovery of SNP markers, which have increased the chances of identifying genomic regions and explain a quantitative trait on complex genomes (Poland et al, 2012;Sabiel et al, 2017). Additionally, high-density SNP arrays have been developed for economically important crops (Sim et al, 2012;Ps et al, 2017;Contreras-Soto et al, 2017a).…”