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Spring durum wheat occupies over 0.5 M ha in Kazakhstan and represents an important domestic and export commodity. This study aimed to characterize 151 durum wheat cultivars and advanced lines originating from eight breeding programs of the Kazakhstan–Siberia Spring Wheat Improvement Network (KASIB) between 2003 and 2018. The phenotypic characterization was performed in two contracting evaluation sites more than 1000 km apart (Almaty in the Southeast and Shortandy in the North) for two years and a total of 11 agronomic traits were recorded. Field trials at both locations followed regional agronomy practices, including sowing, harvesting, and genotype evaluation using a randomized complete block design (RCBD). The growing season was longer in Almaty, resulting in a higher number of grains per spike. Though grains are smaller in size with an overall higher yield, 243 g/m2 versus 170 g/m2, there was no correlation between germplasm performance at the two sites. Molecular characterization was performed with 10 iPBS-retrotransposons primers that resulted in a total of 345 bands and showed a mean polymorphism of 91.9%. Mean values of gene diversity (0.251), Shannon's information index (0.388), and expected heterozygosity (0.233) revealed a relatively high level of genetic diversity in the KASIB set. AMOVA revealed higher genetic variations due to differences within the populations. Marker-based cluster analysis, including STRUCTURE and neighbor-joining algorithms, divided the material into two populations with clear differences in geographic origin. Superiors and diverse germplasm identified in the study are recommended for marker assisted selection and breeding. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a non-essential heavy metal having toxic effects on all living organisms. Durum wheat (Triticum durum Desf.) is widely used in human diets but has the potential to accumulate Cd. It also has a high level of genetic diversity, which may be exploited to develop cultivars with low Cd content. We aimed to perform marker-assisted selection and validate previously identified Cd markers in durum wheat germplasm for use in the investigation of accessions that accumulate low grain Cd content. We assessed 130 durum wheat accessions phenotypically and using three different molecular markers. Grain Cd contents of the studied germplasm varied 4.91-fold (26.2–128.7 μg/kg) with an average of 58.2 μg/kg. Landraces showed lower average values of grain Cd content than cultivars. Three molecular markers (usw47, Cad-5B and KASP marker Cad-5B) were used to differentiate high and low Cd accumulating lines. Results showed high correlation and successfully classified the accessions to the expected high or low Cd level; 87 accessions showed the low Cd alleles, and 43 accessions the high Cd alleles, except for five accessions with the usw47 marker that showed heterozygous status. A significant correlation coefficient (r = 0.944*) was observed among the three molecular markers. Based on molecular markers, 96.2% of the accessions were classified accurately. The KASP assay was highly effective in successfully separating low from high Cd content accessions and could be used as a molecular tool in durum wheat breeding programs, with less cost and time, targeting reduced grain Cd levels. The results of this study will allow durum wheat breeders to accelerate their progress to select suitable genotypes with the desired alleles. Durum wheat (Triticum durum Desf.) has great genetic diversity and is widely used in human diets but has the potential to accumulate Cd, which has significant adverse effects on human health. We assessed 130 durum wheat accessions phenotypically and using three different molecular markers. Results showed that utilisation of appropriate molecular markers will reduce the time and cost for grain Cd evaluation, and will allow durum breeders to accelerate progress to select genotypes with desired alleles. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a non-essential heavy metal having toxic effects on all living organisms. Durum wheat (Triticum durum Desf.) is widely used in human diets but has the potential to accumulate Cd. It also has a high level of genetic diversity, which may be exploited to develop cultivars with low Cd content. We aimed to perform marker-assisted selection and validate previously identified Cd markers in durum wheat germplasm for use in the investigation of accessions that accumulate low grain Cd content. We assessed 130 durum wheat accessions phenotypically and using three different molecular markers. Grain Cd contents of the studied germplasm varied 4.91-fold (26.2–128.7 μg/kg) with an average of 58.2 μg/kg. Landraces showed lower average values of grain Cd content than cultivars. Three molecular markers (usw47, Cad-5B and KASP marker Cad-5B) were used to differentiate high and low Cd accumulating lines. Results showed high correlation and successfully classified the accessions to the expected high or low Cd level; 87 accessions showed the low Cd alleles, and 43 accessions the high Cd alleles, except for five accessions with the usw47 marker that showed heterozygous status. A significant correlation coefficient (r = 0.944*) was observed among the three molecular markers. Based on molecular markers, 96.2% of the accessions were classified accurately. The KASP assay was highly effective in successfully separating low from high Cd content accessions and could be used as a molecular tool in durum wheat breeding programs, with less cost and time, targeting reduced grain Cd levels. The results of this study will allow durum wheat breeders to accelerate their progress to select suitable genotypes with the desired alleles. [ABSTRACT FROM AUTHOR]

Durum wheat (Triticum turgidum L.) is the 10th most cultivated crop and is a vital food source for human consumption. Genetic diversity in durum wheat is still an unexplored subject, and gene banks are filled with accessions waiting to be screened. Here, four different groups of durum wheat, Turkish and foreign cultivars, and in situ and ex situ landraces were evaluated for population structure and genetic diversity. A collection of 129 durum wheat accessions were genotyped, with a total of 6,357 markers (SilicoDArT, SNP [single‐nucleotide polymorphism], and simple sequence repeats [SSRs]). The highest mean allele number per marker (1.562) was obtained with SNP markers in ex situ landraces; the lowest mean allele number per marker (0.788) was obtained with SSR markers in the foreign cultivars. The minimum percentage of polymorphic loci was 38.70% observed with SSR markers in foreign cultivars; the maximum was 76.20% in SilicoDArT markers in ex situ landraces. According to Neighbor‐Joining analyses, the studied collection was divided into groups of cultivars and landraces, with some level of admixtures. Structure and principal coordinate analysis obtained distinct clusters for ex situ landraces and foreign cultivars, supported by Neighbor‐Joining analysis. A significant level of intergroup and intragroup variation was observed, and Turkish ex situ landraces were found as the most diverse and distinct group in the collection. Turkish landraces may be a promising source of novel allelic diversity that can be used in durum wheat breeding worldwide. Core Ideas: Turkish durum wheat landraces may provide novel allelic diversity.Turkish durum wheat cultivars released in the late 20th century has close pedigree relations with foreign cultivars.Turkish modern wheat germplasm/gene pool have experienced a bottleneck for several reasons.Turkish cultivars divide into two distinct groups: foreign related and landrace related. [ABSTRACT FROM AUTHOR]

Einkorn (Triticum monococcum L. ssp. monococcum) is an ancient diploid wheat species with many useful traits and used as a wheat gene discovery model. In this research, a total of 41 diploid and tetraploid wheat accessions were tested using simple sequence repeat (SSR) markers. A total of 33 genotypes of T. monococcum along with four genotypes each of tetraploid wheat (T. dicoccon and T. durum) were used as plant material. The analysis utilized 10 polymorphic markers, including a total number of 41 alleles with an average frequency of 4.1 alleles per locus during exploration of the level of genetic variations. Various diversity analyses, which are the effective number of alleles (Ne), gene diversity (h), Polymorphic Information Content (PIC), and Shannon's information index (I), were performed for 10 'A' genome wheat SSR markers. The results showed a narrow variation in einkorn genotypes, supported by Analysis of Molecular Variance (AMOVA), with 66% maximum variation in all genotypes. The structure analysis divided the whole germplasm into two populations. A dendrogram was constructed to determine the genetic similarities using the unpaired group method with arithmetic averages (UPGMA), which separated tetraploid wheat from other genotypes/accessions. Principal Coordinate Analysis (PCoA) co-supported the clustering of UPGMA and structure by differentiating the diploid and tetraploid wheat. These findings will help understand the genetic relationships among these wheat accessions and their use in breeding programs in the future works. [ABSTRACT FROM AUTHOR]

Until now, little attention has been paid to the geographic distribution and evaluation of genetic diversity of durum wheat from the Central Fertile Crescent (modern-day Turkey and Syria). Turkey and Syria are considered as primary centers of wheat diversity, and thousands of locally adapted wheat landraces are still present in the farmers’ small fields. We planned this study to evaluate the genetic diversity of durum wheat landraces from the Central Fertile Crescent by genotyping based on DArTseq and SNP analysis. A total of 39,568 DArTseq and 20,661 SNP markers were used to characterize the genetic characteristic of 91 durum wheat land races. Clustering based on Neighbor joining analysis, principal coordinate as well as Bayesian model implemented in structure, clearly showed that the grouping pattern is not associated with the geographical distribution of the durum wheat due to the mixing of the Turkish and Syrian landraces. Significant correlation between DArTseq and SNP markers was observed in the Mantel test. However, we detected a non-significant relationship between geographical coordinates and DArTseq (r = -0.085) and SNP (r = -0.039) loci. These results showed that unconscious farmer selection and lack of the commercial varieties might have resulted in the exchange of genetic material and this was apparent in the genetic structure of durum wheat in Turkey and Syria. The genomic characterization presented here is an essential step towards a future exploitation of the available durum wheat genetic resources in genomic and breeding programs. The results of this study have also depicted a clear insight about the genetic diversity of wheat accessions from the Central Fertile Crescent. [ABSTRACT FROM AUTHOR]