Genetic diversity of Sesame (Sesamum indicum L) using high throughput diversity array technology

Tesfaye Tewodros,Tesfaye Kassahun,Keneni Gemechu,Ziyomo Cathrine,Alemu Tesfahun 한국작물학회 2022 Journal of crop science and biotechnology Vol.25 No.4

Sesame is an important oil crop widely cultivated in Africa and Asia. Characterization of genetic diversity and population structure of sesame genotypes in these continents can be used to designing breeding methods. In the present study, 300 genotypes comprising 209 Ethiopian landraces, and 75 exotic collections from diferent African and Asia countries, and 16 varieties were used. The panel was genotyped using two high-throughput diversity array technology markers. A total of 6115 silicoDArT and 6474 SNP markers were reported, of which 5065 silicoDArT and 5821 SNP markers were aligned with the reference sesame genome. For further analysis, it was fltered with an allele frequency for each SNP site and left 2997 highquality SNPs. All genotypes used in this study were descended from eight geographical origins. The average diversity of the panel was 0.14. Considering the genotypes based on their geographical origin, Africa collections (0.21) without Ethiopian collection was more diverse, when further portioned Africa, North Africa (0.23) collection was more diverse than others, but at the continent level, Asia (0.17) was more diverse than Africa (0.14). The genetic distance among the populations was ranged from 0.015 to 0.394. The populations were clustered into four groups. The structure analysis was divided into four hypothetical ancestral populations and 21 genotypes were an admixture. This indicate genotypes from the same origin didn’t classify on the country of origin. The genetic diversity and population structure guide future research work to design association studies and the systematic utilization of genetic resource.

Genetic Diversity of Ethiopian Tef [(Eragrostis tef (Zucc.) Trotter] Released and Selected Farmers’ Varieties along with Two Wild Relatives as Revealed by Microsatellite Markers

Tsion Fikre,Kassahun Tesfaye,Kebebew Assefa 한국작물학회 2018 Journal of crop science and biotechnology Vol.21 No.4

Knowledge on the extent and pattern of diversity in crop species is a precondition for any crop improvement as it helps breeders in determining apt breeding approaches. The genetic diversity of 49 tef genotypes (36 improved varieties, 10 farmers’ varieties, 3 elite lines) and 2 wild relatives was investigated using nine SSR markers. A total of 52 alleles were amplified with a mean of six alleles per locus, and mean polymorphic information content and gene diversity values of 0.69 and 0.73, respectively. The analysis of molecular variance showed higher percentage of variation within individuals (60%) and the variation among groups was the least (10%).The lowest pair-wise genetic differentiation and highest gene flow were observed among the varieties obtained through hybridization and direct selection. Genetic distance analysis showed the smallest (GD=0.101) between varieties from direct selection and hybridization and the largest (GD= 0.454) between wild Eragrostis accessions and cultivated tef accessions. The dendrogram based on the cluster analysis grouped the tested genotypes into three major clusters. PCoA showed that the first three most informative principal coordinates accounted 29% of the genetic variation. In summary, the farmer’s varieties are distant from the improved varieties and represent more genetic diversity. This finding is of interest to national breeding program to use the farmer’s material as a source of genetic variation for traits of interest. Similarly, wild relatives showed highest genetic distance however, further investigation is required in order to identify useful genes controlling agro-morphological characters.

Genetic diversity analysis of advanced chickpea (Cicer arietinum L.) genotypes in Ethiopia for identification of high-yielding and novel Fusarium wilt resistance sources

Dagnachew Bekele,Kassahun Tesfaye,Asnake Fikre 한국작물학회 2021 Journal of crop science and biotechnology Vol.24 No.2

Chickpea (Cicer arietinum L.) is one of the most important food legumes in the world. However, Fusarium wilt is one of the major yield limiting factors in chickpea. Breeding for host plant resistance is the most cost-efficient and eco-friendly strategy to control the disease. The deployment of resistant varieties has not been extensively used due to lack of stable resistance source with desirable yield and yield-related morphological traits in cultivated chickpea with a narrow genetic base for traits’ improvement. Therefore, creating significant genetic diversity is a fundamental step to develop Fusarium wilt-resistant varieties. In this study, 47 advanced recombinant inbred lines derived from multi-parent intraspecifi c crosses and three checks were assessed for Fusarium wilt resistance and major yield-related morphological traits for two consecutive years. Analysis of variance showed the presence of significant difference ( P < 0.05) among test genotypes for major yield�related morphological traits. Consistently, multivariate analyses showed high genetic diversity between test genotypes. Cluster analysis grouped test genotypes into four distinct clusters. The fi rst two principal coordinates with eigenvalues greater than one accounted for 93.94% of the total variation suggesting high genetic diversity between test genotypes. Based on these, we identified 20 high-yielding and novel Fusarium wilt-resistant genotypes with mean wilt incidence of 3.83%. Therefore, these genotypes can be utilized in any chickpea breeding program as a novel Fusarium wilt resistance sources to develop wilt-resistant varieties with high yield and yield-related morphological traits.

Molecular characterization of Arabica Coffee (Coffea arabica L.) germplasms and their contribution to biodiversity in Ethiopia

Dida Gudeta,Bantte Kassahun,Disasa Tesfaye 한국식물생명공학회 2021 Plant biotechnology reports Vol.15 No.6

Ethiopia is the center of origin and diversity for Arabica coffee with high morphological diversity between accessions as compared to commercial cultivars. Coffee germplasm collection and molecular characterization are crucial steps towards its conservation, breeding, and development of superior genotypes for various end uses. Hence, this study was initiated with the objective of studying the genetic diversity of Coffea arabica accessions collected from different regions of Ethiopia, using SSR markers. A total of 20 SSR markers were used to genotype 86 accessions and produced a total of 112 alleles, with an average of 5.6 alleles per locus. All the loci across the entire populations were found to be highly polymorphic with a mean of 0.6 PIC value. Average observed heterozygosity and allelic richness across all populations ranged from 0.22 to 0.27 and 3.52–4.26, with a mean of 2.43 and 3.97, respectively. AMOVA showed high variation within population based on geographical origin. The smaller Fst (0.037) observed indicates the presence of lower population genetic differentiation as a result of higher gene flow (Nm = 2.45) across populations and the lowest mean genetic distance (0.21) observed between populations. The UPGMA, PCoA, and structure analysis poorly grouped the individuals into distinct clusters indicating the presence of population admixture. The observed higher genetic variability in all populations indicates that the country has huge coffee genetic diversity which can be used for future coffee improvement. Our results revealed an unexploited highly diverse genetic resource particularly from Omo, Ilubabor, and Benchi Maji that should be considered in future coffee breed- ing program and germplasm conservation.

Variations in mitochondrial cytochrome b region among Ethiopian indigenous cattle populations assert Bos taurus maternal origin and historical dynamics

Tarekegn, Getinet Mekuriaw,Ji, Xiao-yang,Bai, Xue,Liu, Bin,Zhang, Wenguang,Birungi, Josephine,Djikeng, Appolinaire,Tesfaye, Kassahun Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.9

Objective: This study was carried out to assess the haplotype diversity and population dynamics in cattle populations of Ethiopia. Methods: We sequenced the complete mitochondrial cytochrome b gene of 76 animals from five indigenous and one Holstein Friesian${\times}$Barka cross bred cattle populations. Results: In the sequence analysis, 18 haplotypes were generated from 18 segregating sites and the average haplotype and nucleotide diversities were $0.7540{\pm}0.043$ and $0.0010{\pm}0.000$, respectively. The population differentiation analysis shows a weak population structure (4.55%) among the populations studied. Majority of the variation (95.45%) is observed by within populations. The overall average pair-wise distance ($F_{ST}$) was 0.049539 with the highest ($F_{ST}=0.1245$) and the lowest ($F_{ST}=0.011$) $F_{ST}$ distances observed between Boran and Abigar, and Sheko and Abigar from the indigenous cattle, respectively. The phylogenetic network analysis revealed that all the haplotypes detected clustered together with the Bos taurus cattle and converged to a haplogroup. No haplotype in Ethiopian cattle was observed clustered with the reference Bos indicus group. The mismatch distribution analysis indicates a single population expansion event among the cattle populations. Conclusion: Overall, high haplotype variability was observed among Ethiopian cattle populations and they share a common ancestor with Bos taurus.