Genetic diversity and association analysis among Egyptian barley (Hordeum vulgare L.) genotypes with different adaptations to saline conditions analyzed by SSR markers

Abstract

The success of salt tolerance breeding programs employing traditional screening and selection has been limited in the past decades. This study was designed to characterize the genetic diversity within a subset of barley germplasm using microsatellite markers under different adaptations to salt conditions. Twenty-five microsatellites (SSR) representative of the barley genome, were used in 30 barley accessions and cultivars. A total of 59 alleles were generated, the mean number of alleles per locus was 2.4 and the PIC was 0.22. The four genomic Locus Bmac0030, Bmag0125, EBmac0701 and EBmac0871 were sufficient to differentiate the diversity of all genotypes since they generated a high number of allele with high PIC values. Cluster analysis UPGMA based on SSRs data clearly the most differentiate genotypes according to their Salinity tolerance and the PCA recorded 58.8 % of the total variance. Five markers pairs were found to be associated with salinity and showed linkage disequilibrium with r 2 values higher than 0.05. Association analysis along with specific significant alleles of grain yield showed a significant association of the marker Bmag749 (2H, 176 bp) with salinity. Our results shown a small sample and limited markers were used in this study and the results need to be confirmed using linkage mapping with a large association population. However, the results are credible because many of the loci that were identified were associated with traits that were common with previous reports of linkage or association mapping. These will be useful for molecular marker assist selection and molecular design breeding.

Genome‐wide transcriptomic and functional analyses provide new insights into the response of spring barley to drought stress

“…Drought stress tolerance is complex; therefore, illustrating the molecular mechanism controlling drought tolerance has been the long-term relevance of barley breeders (Elakhdar et al, 2022). The main objective of the Egyptian barley breeding program is to develop new cultivars with high yield potential and tolerance to different biotic and abiotic stresses (salinity, drought, diseases, poor soil fertility and insects) (Elakhdar et al, 2016a;Elakhdar et al, 2016b;Elakhdar et al, 2018;Sallam et al, 2019a;Sallam et al, 2019b). To realize these goals, the barley program has developed several breeding strategies, including the screening of exotic and local materials in field trials and utilizing elite materials as parents.…”

Inheritance Pattern of Earliness and Yield Related-Traits in Spring Barley (Hordeum vulgare L.)

“…Yield, as well as yield components, is determined by several genes, with specific interactions that make breeding for yield increase more difficult. Different degrees of gene effects, i.e., partial to over-dominance, were clear to be involved in the inheritance of FL, KW and GY/plant (Abd El-Aty et al, 2011;Elakhdar et al, 2016a).…”

Genetic diversity and population structure assessment of Western Canadian barley cooperative trials

“…Several molecular markers have been used to measure genetic diversity, population structure, association studies, evolutionary origin, and breeding applications in barley. So far, simple sequence repeats (SSRs), Diversity arrays Technology (DArT), and single-nucleotide polymorphisms (SNPs) based on next-generation sequencing (NGS) have been utilized intensively in barley genetic diversity studies ( Rafalski, 2002 ; Kumar et al., 2012 ; Elakhdar et al., 2016a ; Elakhdar et al., 2016b ; Elakhdar et al., 2018 ; Capo-Chichi et al., 2021 ). In barley, high-throughput SNP genotyping has revolutionized genome-wide association (GWAS) and gene mapping studies in recent years due to the development of high-throughput genotyping platforms.…”