1. The 6th SPPS PhD conference, 2-5 September, 2010, Espoo, Finland
Genetic diversity of cultivated barley landraces in Iran measured using microsatellites
Hamed KHODAYARI1, Azadeh Akhavan1, Hojjatollah Saeidi1, Mohammad Reza Rahiminejad1 and Takao Komatsuda2
1. Department of Biology, University of Isfahan, Isfahan, Iran
2. Genome Research Department, National Institute of Agrobiological Science (NIAS), Tsukuba, Ibaraki, Japan Dept. of Biology, University of Idfahan, Isfahan, Iran
Abstract:
The cultivated barley (Hordeum vulgare subsp. vulgare) is one of the major crops in the world, cultivated in all temperate areas. Because there is not enough information about genetic diversity of barley landraces in Iran, in this study the genetic diversity of its landraces was evaluated using 26 microsatellite markers. The genetic diversity between 42 accessions (13 accessions of two-rowed and 29 accessions of six-rowed barley) collected from various regions of Iran was assessed. A total number of 161 alleles were found from 26 SSR loci. A high level of polymorphism information content (PIC; average = 0.663), genetic diversity (0.705) and allele number per locus (6.19) were observed. In dendrograms constructed based on the SSR data, the cultivars distichon (two-rowed) and hexastichon (six-rowed) were separated. Based on the results of this study, it can be concluded that there is a high level of genetic diversity between the barely landraces in Iran and that the barely Iranian gene pool is valuable source to search for new useful alleles for crop improvement.
Results:
The 26 primer pairs assayed 26 loci with 161 alleles (Table 2). About 31 of these alleles were rare (frequency < 0.05) among the landraces and only one allele (175 bp at loci HvMLOH1A on 4H) was observed frequently (frequency >0.95). The overall average number of alleles per loci was The gene diversity between loci varied between and Total average genetic diversity of material was Three of the 26 loci showed more than 10 alleles per locus. The alleles for the 26 loci were distributed among the four region of origin (W, SW, N and NE) as follows: 101 alleles for W, 90 for SW, 44 for N and 59 for NE. Only one allele each was detected for the Bmac067 loci in the W accessions, the HVMLOH1A locus in the SW accessions, the EBmac602, HVMLOH1A, Bmac067 and EBmac906 loci in the N accessions and the WMC1A, HVMLOH1A and Bmac067 in NE accessions. In genetic distance based dendrogram, the accessions of two and six rowed barley were clearly separated.
Fig 1. Distribution of barley in different regions of Iran
Introduction:
Cultivated barley (Hordeum vulgare subsp. vulgare) is one of the most important crop cereal in the tribe Triticeae (poacea) that cultivated over the temperate regions. Based on several reports it has been originated from Fertile crescent in Near East or from Tibetan in the west China. Iran is placed in the southeastern edge of Fertile Crescent from where a, based on several evidences, the cultivation process of barley have took placed. Regarding the high variable geographical and ecological conditions in Iran, the Iranian old landraces can be considered as valuable gene sources for modern cultivar improvement. The study of genetic diversity in a germplasm such as barley landraces is fundamental to perform a strategy for landrace conservation and to find germplasem with higher priority.
Discussin:
The traditional landraces and wild relatives of cultivated cereals are important gene sources to broaden the genetic bases of modern cultivars, which have narrowed gene pool due to intensive breedings. The gemplasms presented in the center of diversity and those grow in the regions with high degree of geographical and ecological diversity would be of highest importance. Based on the results of this study, high level of genetic diversity was observed in Iranian barley germplasm. The genetic diversity was distributed all over the different regions and there were no groupings related to the origin of accessions. The two and six rowed varieties were separted indicated that these two varieties are geneticaly distant and have probably different origins. We would expect that the Iranian barley germplasm is of high value to serve as gene source for barley improvement and to find new usefull alleles for breeding proposes.
Matherials and methods:
42 accessions of Iranian barley landraces were collected from different regions of Iran. In order to assessing genetic diversity, 26 SSR markers derived from wild barley were used. PCR amplification were carried out in 10 μL, containing approximately ng template genomic DNA, 250 nM of each primer, 0.2 mM of each dNTP, 1.5 mM Mgcl2, 1.2 U EX-Taq polymerase. PCR amplification procedure of SSRs marker was performed by an initial denaturation step of 5 min at 94 °C followed by 30 cycles of three steps: denaturation for 30 s at 94 °C, annealing for 30 s at 55–60 °C, extension for 30 s at 72 °C with a final extension for 7 min at 72 °C (Liu et al. 1996). The microsatellite data were analyesd by PowerMarker software, and diversity parameter such as gene diversity, PIC and major allele frequency were calculated. A genetic distance based UPGMA tree showing relationships among accessions was generated. Analyses of molecular variance (AMOVA) implemented in ARLEQUIN software was performed to partition the diversity to among accessions and among different geographic regions
Fig. 2. Genetic distance based dendrogram showing relationships among barley accessions.
The 6th SPPS PhD conference, 2-5 September, 2010, Espoo, Finland