Ahu Altinkut Uncuoglu

Genetic Diversity of Winter Wheat ( Triticum aestivum L.) Revealed by SSR Markers

Wheat (Triticum aestivum L.) is the most important crop for Turkey, which is also one of the gene centers of wheat (Gökgöl 1939; Vavilov 1950; Harlan 1971; Özkan et al. 2002). Genetic variability is of prime importance for the improvement of many crop species, including wheat, and nearly all crop improvement programs depend on genetic diversity in the available germplasm (Graner et al. 1994; Sorrells and Wilson 1997). Molecular markers based on polymerase chain reaction (PCR) methods, such as simple sequence repeats (SSRs) or microsatellites, have become important genetic markers in a wide range of crop species, including wheat (Ma et al. 1996). SSR markers are abundant, dispersed throughout the genome, and show higher levels of polymorphism than other genetic markers (Russell et al. 1997). These features, coupled with their ease of detection, make them ideal for identifying and distinguishing between accessions that are genetically very similar (Saker et al. 2005). Various studies have used SSR markers to investigate genetic diversity in cultivated hexaploid wheat genotypes of T. aestivum L. (Dreisigacker et al. 2005; Liu et al. 2005; Hao et al. 2006; Landjeva et al. 2006; Salem et al. 2008; Schuster et al. 2009). SSR markers have been successfully employed to characterize genetic diversity in seed bank collections of improved wheat germplasm (Börner et al. 2000; Huang et al. 2002) and wild relatives (Li et al. 2000; Hammer 2000).

Cytological changes in Turkish durum and bread wheat genotypes in response to salt stress

Effects of salt stress on root growth, mitotic index, nuclear volume, vacuolization, nucleolar distortion and starch content were investigated in Turkish bread wheat ( Triticum aestivum L. cvs. Yildiz - salt sensitive, Dagdas - salt tolerant) and durum wheat ( Triticum durum L. cvs. C1252 - salt sensitive, Meramsalt tolerant) genotypes which were treated with 150 mM NaCI over a 6-day period. Salt treatment of wheat seedlings resulted in a decrease in root elongation and cell division in all genotypes at the 48 hours. According to controls, wheat root length decrease was 49% for Dagdas, 53.34% for Yildiz, 25.34% for Meram, 53.68% for C1252 at the 48 h. Mitotic index showed a more significant decrease in sensitive genotypes (1.24% for Yildiz, 0.66% for C1252 compairing to their controls 3.85% and 3.72%, respectively) of bread and durum wheat rather than tolerant ones (2.21% for Dagdas, 1.57% for Meram compairing to their controls 4.12% and 5.88%, respectively) at the 48 h of salt treatment. Calculated nuclear volume of wheat genotypes besides Dagdas showed a decline at the 48 h ranged from 1.57x10(5) to 2.13x10(5) μm(3) . Vacuolization and nuclear distortion appeared on DAPI-stained preparations. There was a clear reduction in starch content in salt treated genotypes of durum wheat.

Genomic Evaluation of Sunflower Broomrape (Orobanche Cumana) Germplasm by KASP Assay

Abstract Orobanche cumana Wallr. is a holoparasitic plant for only sunflower, hence it is called as sunflower broomrape. Yield loss created by O. cumana which is generally 50 % can reach to 100 %. In this study, it was planned to perform molecular characterization of O. cumana germplasm as nine locations of Thrace region obtained from Trakya Agricultural Research Institute by using Single Nucleotide Polymorphism (SNP) markers, widely used in plant breeding programs, in Competitive Allele Specific PCR (KASP) assay which is a fluorescent tagged allele specific PCR method based, economic, reliable and easily repeatable genotyping technology. Databases and literature were scanned to spot variations on O. cumana genome which is not known clearly. So far, four SSR (Simple Sequence Repeat) marker (Ocum-197, Ocum-006, Ocum-023 and Ocum-151) regions showing polymorphic pattern were used for searching possible SNPs. Primer pairs were designed for amplification of the regions possibly having SNPs and PCR amplifications with these primer pairs were performed and 1 candidate deletion was detected on the amplicon which was amplified by Ocum-197 SSR marker. Following, the deletion was converted to KASP primers and KASP assay was performed. The deletion marker, Del-197, has grouped the samples from nine locations in the resulting allelic discrimination plot and infestation was performed according to this grouping, As a conclusion, Del-197 is considered as a selective marker for the ability to rapidly assay allelic variation at DNA markers for O. cumana populations that have effects on infestation results were evaluated as races, F, G, H and I in Thrace region.

SSR Markers Suitable for Marker Assisted Selection in Sunflower for Downy Mildew Resistance

Abstract The effectiveness of Pl genes is known to be resistant to downy mildew (DM) disease affected by fungus Plasmopara halstedii in sunflower. In this study phenotypic analysis was performed using inoculation tests and genotypic analysis were carried out with three DM resistance genes Plarg, Pl13 and Pl8. A total of 69 simple sequence repeat markers and 241 F2 individuals derived from a cross of RHA-419 (R) x P6LC (S), RHA-419 (R) x CL (S), RHA-419 (R) x OL (S), RHA419 (R) x 9758R (S), HA-R5 (R) x P6LC (S) and HA89 (R) x P6LC (S) parental lines were used to identify resistant hybrids in sunflower. Results of SSR analysis using markers linked with downy mildew resistance genes (Plarg, Pl8 and Pl13) and downy mildew inoculation tests were evaluated together and ORS716 (for Plarg and Pl13), HA4011 (for Pl8) markers showed positive correlation with their phenotypic results. These results suggest that these markers are associated with DM resistance and they can be used successfully in marker-assisted selection for sunflower breeding programs specific for downy mildew resistance.

Molecular Evaluation of Genetic Diversity in Wild-Type Mastic Tree (Pistacia lentiscus L.)

In this study, the patterns of genetic variation and phylogenetic relationships of mastic tree (Pistacia lentiscus L.) genotypes including 12 males and 12 females were evaluated using SSR, RAPD, ISSR, and ITS markers yielding 40, 703, 929 alleles, and 260–292 base pairs for ITS1 region, respectively. The average number of alleles produced from SSR, RAPD, and ISSR primers were 5.7, 14, and 18, respectively. The grouping pattern obtained from Bayesian clustering method based on each marker dataset was produced. Principal component analyses (PCA) of molecular data was investigated and neighbor joining dendrograms were subsequently created. Overall, the results indicated that ISSR and RAPD markers were the most powerful to differentiate the genotypes in comparison with other types of molecular markers used in this study. The ISSR results indicated that male and female genotypes were distinctly separated from each other. In this frame, M9 (Alaçatı) and M10 (Mesta Sakız Adası-Chios) were the closest genotypes and while F11 (Seferihisar) and F12 (Bornova/Gökdere) genotypes fall into same cluster and showing closer genetic relation. The RAPD pattern indicated that M8 (Urla) and M10 (Mesta Sakız Adası-Chios), and F10 (Mesta Sakız Adası-Chios) and F11 (Seferihisar) genotypes were the closest male and female genotypes, respectively.

Genetic Diversity, Population Structure, and Linkage Disequilibrium in Bread Wheat (Triticum aestivum L.)

Bread wheat (Triticum aestivum L.) gene pool was analyzed with 117 microsatellite markers scattered throughout A, B, and D genomes. Ninety microsatellite markers were giving 1620 polymorphic alleles in 55 different bread wheat genotypes. These genotypes were found to be divided into three subgroups based on Bayesian model and Principal component analysis. The highest polymorphism information content value for the markers resides on A genome was estimated for wmc262 marker located on 4A chromosome with the polymorphism information content value of 0.960. The highest polymorphism information content value (0.954) among the markers known to be located on B genome was realized for wmc44 marker located on 1B chromosome. The highest polymorphism information content value for the markers specific to D genome was found in gwm174 marker located on 5D chromosome with the polymorphism information content value of 0.948. The presence of linkage disequilibrium between 81 pairwise SSR markers reside on the same chromosome was tested and very limited linkage disequilibrium was observed. The results confirmed that the most distant genotype pairs were as follows Ceyhan-99—Behoth 6, Gerek 79—Douma 40989, and Karahan-99—Douma 48114.