نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانش‌آموخته کارشناسی ارشد، گروه بهنژادی و بیوتکنولوژی گیاهی، دانشکده کشاورزی، دانشگاه تبریز، تبریز، ایران
2 استاد، گروه بهنژادی و بیوتکنولوژی گیاهی، دانشکده کشاورزی، دانشگاه تبریز، تبریز، ایران
3 دانشیار پژوهش، موسسه تحقیقات دیم کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، مراغه، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Introduction
Knowledge of the level of genetic diversity and its estimation in plant germplasms is the basis of many breeding programs. Due to high levels of polymorphism, high reproducibility, polyallelic nature, codominant scoring, and high genomic frequency, microsatellite (SSR) markers are used widely in investigating genetic diversity and determining the relationships between genotypes. This research aimed to study the genetic diversity of 40 barley genotypes in terms of SSR markers and to determine the markers with the highest discriminating ability.
Materials and methods
In this research, the genetic diversity of 39 barley cultivars and one wild barley genotype was investigated in terms of 57 SSR markers, of which 51 polymorphic markers with clear and acceptable amplification were selected for molecular evaluation of the genotypes. The banding pattern of markers was scored as one (presence of the band) and zero (absence of the band) and also, as the codominance state. Then, the efficiency of the markers was evaluated by the polymorphism information content, frequency of common alleles, number of alleles, observed heterozygosity, and gene diversity. In addition, barley genotypes were grouped by cluster analysis with the Minimum Evolution algorithm and the P-Distance coefficient.
Research findings
Totally, 200 alleles (with an average of 3.92 alleles per locus) were amplified. The average polymorphism information content and gene diversity for these markers were 0.48 and 0.54, respectively. The frequency of common alleles ranged from 0.25 to 0.92 with an average of 0.56, which belonged to the GBMS021 and GBM1275 markers, respectively. Also, the GBMS027 marker had the highest polymorphism information content, expected heterozygosity, and allele number. Cluster analysis assigned the genotypes into three groups. The first group had the highest number of genotypes from the temperate regions (either warm or cold) with spring growth habit. The second group consisted mainly of genotypes from the temperate and cold regions with spring and intermediate growth habits. The third group was mostly a mixture of genotypes from temperate and tropical regions with the intermediate and spring growth habit, and most foreign genotypes were also assigned to this group. However, cluster analysis based on SSR markers couldn’t fully separate the genotypes of different geographical regions, and with different growth habits.
Conclusion
In general, there was significant genetic diversity among the barley genotypes studied in terms of SSR markers, and the markers GBMS027, GBMS021, GBMS006, GBMS180, GBMS0160, GBM1272, and GBMS002 were identified as markers with the highest discriminating ability due to having the higher amount of polymorphic information content, expected heterozygosity, and allele number. This diversity can be utilized in the barley breeding programs.
کلیدواژه‌ها [English]
)