1,721,003 research outputs found
Untapped Genetic Resources for Breeding Acidic Soil-Adapted Chickpea (Cicer arietinum L.) Cultivars
Get PDFGlobally, more than half of potentially arable land is acidic, and aluminum (Al) is the primary factor limiting plant growth and crop productivity on acidic soils worldwide. The development and utilization of Al-tolerant crops is a sustainable approach to enhancing crop production on acidic soils. For this purpose, screening available genetic resources under Al-stressed conditions is a crucial initial step. Hence, the present study aimed to evaluate the Al tolerance of 264 Ethiopian chickpea landraces under hydroponic conditions without Al (control) and with 120 mu M Al (Al treatment). Significant (p < 0.001) variations were detected among the genotypes for all studied traits under control (0 mu M Al) and 120 mu M Al concentration. The relative growth values for the 120 mu M Al/0 mu M Al ratio was also significant, indicating the presence of a considerable amount of genetic variation in Ethiopian chickpea landraces in terms of Al tolerance. Based on relative root growth (RRG) as an Al-tolerance parameter, the genotypes were grouped into five distinct (p < 0.001) classes. The highest RRG value (1.59) was obtained for genotype ETC_209008, followed by ETC_41184 and ETC_212589, while ETC_208995 had the lowest RRG value of 0.27. Of the total landraces screened, 35% had higher RRG values than the tolerant genotype ETC_WL_1_2016 used as a reference, indicating the presence of adequate genotypes capable of outperforming the reference genotype on acidic soils. The genotypes identified in the present study may serve as sources of novel alleles in genes regulating Al tolerance in chickpea that can be utilized in breeding programs to improve the crop's adaptation to acidic soils, thus contributing to smallholder farmers' increased nutritional and food security
Genetic Variability of Ethiopian Chickpea (Cicer arietinum L.) Landraces for Acid Soil Tolerance
Get PDFChickpea is among the major legume crops grown globally. In Ethiopia, it plays a vital role in the food security and economic stability of smallholder farmers. However, its production is often hampered by abiotic factors, particularly soil acidity, which is a major yet often overlooked challenge. Using tolerant genotypes alone or combined with soil amendments is a sustainable approach to improving chickpea production in acidic soils. Hence, the present study assessed the genetic variation of 64 Ethiopian chickpea accessions for acidic-soil tolerance using simple lattice design-based field experiments with two replications at two sites with acidic soil, Emdebir and Holetta. The study revealed significant genetic variation among the evaluated accessions for acid soil tolerance. The study also identified tolerant and high-yielding chickpea accessions with a high yield stability index (YSI) at both test sites. The landrace ETC_B_1_2016 exhibited the highest number of primary branches per plant (NPB), number of pods per plant (NPP), and total seed yield (TSY) at the Emdebir acidic soil trial. At the Holetta acidic soil trial, the landrace ETC_41237 recorded the highest TSY, followed by ETC_K_3_2016 and ETC_B_1_2016, while Akaki had the least. In addition, 14 accessions had the highest TSY and YSI at the Emdebir site, while 16 had the highest YSI at the Holetta site. Notably, NPP displayed the strongest positive correlation with TSY at both sites, irrespective of lime application. Higher genetic variance and broad-sense heritability observed for NPP, hundred-seed weight (HSW), and TSY suggest that genetic factors mainly influence these traits and are more likely to improve through selection. The identified acid-tolerant and high-yielding accessions could be considered for direct cultivation in areas with acidic soils, potentially increasing chickpea productivity. Additionally, these accessions can be crossbred with existing improved varieties to enhance their adaptability to acidic soils, ultimately contributing to food security in regions affected by soil acidity
Multi-Location and Multi-Year Field Trials Revealed Broad-Spectrum Resistance of Sorghum (Sorghum bicolor (L.) Moench) to Anthracnose (Colletotrichum sublineola)
Get PDFEthiopia is one of the centers of origin for sorghum (Sorghum bicolor (L.) Moench), where distinct agro-ecological zones have significantly contributed to its genetic diversity. Although the magnitude varies among the country's regions, sorghum production is severely constrained by anthracnose caused by Colletotrichum sublineola, causing significant grain and biomass losses. This study was conducted to identify sorghum landraces grown in Ethiopia with broad-spectrum resistance and to assess the effect of environments on sorghum anthracnose interaction. In the 2022 cropping season, 285 sorghum accessions, the vast majority of which were landraces, were evaluated at five diverse locations, i.e., Assosa, Bako, Chiro, Haramaya, and Pawe in 2015, 2016, and 2022. Accessions were evaluated according to their initial, final, and mean anthracnose severity scores and the area under the disease progress curve. Analysis of variance (ANOVA) revealed significant differences among accessions, locations, and genotype-by-environment interactions. Based on their reaction to the disease, accessions were categorised into different resistance classes. Most of the accessions were susceptible to anthracnose in the western sites of the country (Assosa, Bako and Pawe) than in the eastern part (Chiro and Haramaya). Among the tested accessions, landraces ETSL100267, ETSL100152, ETSL100388, ETSL100090, ETSL100284, ETSL100107, IS38279, and ETSL101249, and the variety Bonsa were resistant across all locations in the 2022 field trials, suggesting that these landraces might harbour genes with broad-spectrum resistance or have accumulated multiple resistance genes. This study provided insights into the sources of anthracnose resistance and how environmental conditions affect it, which is highly useful for breeders to select germplasm to develop anthracnose-resistant sorghum varieties that are suitable for both specific environments and a broad adaptation
FATTY ACID PROFILE AND PROXIMATE COMPOSITION OF SIRLOIN AND CHUCK OF SELECTED ETHIOPIA CATTLE TYPES
Get PDFThe fatty acid composition of beef meat is important for nutrition and humanhealth. This study examined the composition of sirloin and chuck of beeffrom three cattle breeds in Ethiopia (Boran, Senga, and Sheko). Twelve bullsaged 18 to 24 months were used, and standard methods were employed tomeasurevariousparameters.Theresultsshowedthatmoisturecontentranged from 64.32 +/- 0.29% in Boran sirloin to 66.47 +/- 0.13% in Sheko sirloin,crude fat ranged from 10.79 +/- 0.36% in Sheko chuck to 13.25 +/- 0.38% inBoran chuck, and crude protein ranged from 21.65 +/- 0.50% in Senga sirlointo26.83 +/- 0.78%inBoranchuck.ThecolorevaluationrevealedL*valuesof28.20 +/- 3.09 to 32.52 +/- 1.70 for senga chuck and Boran chuck, a* values of5.18 +/- 0.88to9.35 +/- 2.96forBoransirloinandSengachuck,andb*valuesof2.24 +/- 1.47 to 4.33 +/- 1.05 for Shekosirloin and Senga sirloin. The dominantfatty acid was Palmitic acid (C16:0), comprising 24.64% to 31.60% of thetotal. The study found that the sirloin cut had significantly higher levels ofmonounsaturated fatty acids (42.38%) and lower levels of polyunsaturatedfattyacidscomparedtothechuckcut.Inconclusion,Shekobeefhadhighermoisture content, while Boran beef had higher levels of crude protein andfat compared to Senga and Sheko. Principal component analysis (PCA)identifiedfattyacidprofilesasthemainfactorsinfluencingvariationamongcattle breeds. This research provides valuable information for cattle breeding and meat quality improvement efforts in Ethiopia and beyond
Modeling of Ethiopian Beef Meat Marbling Score Using Image Processing for Rapid Meat Grading
Get PDFMeat characterized by a high marbling value is typically anticipated to display enhanced sensory attributes. This study aimed to predict the marbling scores of rib-eye, steaks sourced from the Longissimus dorsi muscle of different cattle types, namely Boran, Senga, and Sheko, by employing digital image processing and machine-learning algorithms. Marbling was analyzed using digital image processing coupled with an extreme gradient boosting (GBoost) machine learning algorithm. Meat texture was assessed using a universal texture analyzer. Sensory characteristics of beef were evaluated through quantitative descriptive analysis with a trained panel of twenty. Using selected image features from digital image processing, the marbling score was predicted with R2 (prediction) = 0.83. Boran cattle had the highest fat content in sirloin and chuck cuts (12.68% and 12.40%, respectively), followed by Senga (11.59% and 11.56%) and Sheko (11.40% and 11.17%). Tenderness scores for sirloin and chuck cuts differed among the three breeds: Boran (7.06 +/- 2.75 and 3.81 +/- 2.24, respectively), Senga (5.54 +/- 1.90 and 5.25 +/- 2.47), and Sheko (5.43 +/- 2.76 and 6.33 +/- 2.28 Nmm). Sheko and Senga had similar sensory attributes. Marbling scores were higher in Boran (4.28 +/- 1.43 and 3.68 +/- 1.21) and Senga (2.88 +/- 0.69 and 2.83 +/- 0.98) compared to Sheko (2.73 +/- 1.28 and 2.90 +/- 1.52). The study achieved a remarkable milestone in developing a digital tool for predicting marbling scores of Ethiopian beef breeds. Furthermore, the relationship between quality attributes and beef marbling score has been verified. After further validation, the output of this research can be utilized in the meat industry and quality control authorities
Pathotype determination of sorghum anthracnose (Colletotrichum sublineola) isolates from Ethiopia using sorghum differentials
Get PDFIntroduction Sorghum anthracnose, caused by Colletotrichum sublineola, is the most destructive disease of sorghum, which causes up to 80% grain yield loss in susceptible varieties. The use of resistance varieties is an effective, durable, and eco-friendly strategy for anthracnose control. Knowledge of the phenotypic and genetic variation in C. sublineola is vital for designing appropriate anthracnose management strategies.Methods The present study examined the morphology and virulence of 25 C. sublineola isolates recovered from various sorghum-producing regions of Ethiopia against 18 known sorghum anthracnose differentials, 6 Ethiopian sorghum landraces, and a variety of Bonsa.Results Analysis of variance (ANOVA) revealed significant differences among sorghum genotypes, C. sublineola isolates, and their interactions. There was a significant difference between the isolates in virulence, with each isolate exhibiting virulence in 8-72% of the sorghum genotypes tested. Among the 25 tested isolates, the top four most virulent isolates were from Pawe, suggesting that this area is suitable for pathogen diversity studies and host plant resistance screening. The sorghum genotypes IS_18760, Brandes, and Bonsa showed resistance to all tested isolates. Consequently, they may provide potential sources of resistance genes for sorghum breeding programs to develop cultivars resistant to different C. sublineola pathotypes. However, the resistant check SC748-5 was susceptible to isolates NK73_F37, while another resistant check SC112-14 was susceptible to isolates PW123_F47 and PW122_F47. Cluster analysis grouped 22 isolates into seven clusters based on their morphological characters, whereas 24 pathotypes were identified among 25 isolates that were tested on 25 sorghum genotypes.Discussion Hence, this study revealed high variation in C. sublineola in Ethiopia suggesting the need for broad-spectrum resistance to control the disease. Sorghum genotypes resistant to various C. sublineola isolates were identified in this study, which can be used in sorghum breeding programs aiming to develop resistant cultivars to anthracnose. Highly virulent C. sublineola isolates were also identified which could be used in sorghum germplasm resistance screening. The report is the first to show the existence of C. sublineola pathotypes in Ethiopia
Durum wheat heat tolerance loci defined via a north–south gradient
Get PDFThe global production of durum wheat (Triticum durum Desf.) is hindered by a constant rise in the frequency of severe heat stress events. To identify heat-tolerant germplasm, three different germplasm panels ("discovery," "investigation," and "validation") were studied under a range of heat-stressed conditions. Grain yield (GY) and its components were recorded at each site and a heat stress susceptibility index was calculated, confirming that each 1 degrees C temperature rise corresponds to a GY reduction in durum wheat of 4.6%-6.3%. A total of 2552 polymorphic single nucleotide polymorphisms (SNPs) defined the diversity of the first panel, while 5642 SNPs were polymorphic in the "investigation panel." The use of genome-wide association studies revealed that 36 quantitative trait loci were associated with the target traits in the discovery panel, of which five were confirmed in a "subset" tested imposing heat stress by plastic tunnels, and in the investigation panel. A study of allelic combinations confirmed that Q.icd.Heat.003-1A, Q.icd.Heat.007-1B, and Q.icd.Heat.016-3B are additive in nature and the positive alleles at all three loci resulted in a 16% higher GY under heat stress. The underlying SNPs were converted into kompetitive allele specific PCR markers and tested on the validation panel, confirming that each explained up to 9% of the phenotypic variation for GY under heat stress. These markers can now be used for breeding to improve resilience to climate change and increase productivity in heat-stressed areas.The use of a north-south gradient between the Senegal River and Morocco was introduced to assess heat tolerance.Critical loci, involved in the control of heat tolerance in durum wheat, was defined.Germplasm sources and loci tagged by kompetitive allele specific PCR to favor the introgression of heat tolerance alleles by breeding were presented.A new gold standard by using three germplasm panels to discover, investigate, and validate useful loci was studied
SeqSNP-Based Targeted GBS Provides Insight into the Genetic Relationships among Global Collections of Brassica rapa ssp. oleifera (Turnip Rape)
Get PDFTurnip rape is a multi-purpose crop cultivated in temperate regions. Due to its ability to fit into crop rotation systems and its role as a food and feed source, spring-type turnip rape cultivation is on the rise. To improve the crop's productivity and nutritional value, it is essential to understand its genetic diversity. In this study, 188 spring-type accessions were genotyped using SeqSNP, a targeted genotyping-by-sequencing method to determine genetic relationships between various groups and assess the potential effects of mutations within genes regulating major desirable traits. Single nucleotide polymorphism (SNP) alleles at six loci were predicted to have high effects on their corresponding genes' functions, whereas nine loci had country/region-specific alleles. A neighbor-joining cluster analysis revealed three major clusters (I to III). About 72% of cluster-I accessions were of Asian origin, whereas 88.5% of European accessions and all North American accessions were placed in cluster-II or cluster-III. A principal coordinate analysis explained 65.3% of the total genetic variation. An analysis of molecular variance revealed significant differentiation among different groups of accessions. Compared to Asian cultivars, European and North American cultivars share more genetic similarities. Hence, crossbreeding Asian and European cultivars may result in improved cultivars due to desirable allele recombination. Compared to landraces and wild populations, the cultivars had more genetic variation, indicating that breeding had not caused genetic erosion. There were no significant differences between Swedish turnip rape cultivars and the NordGen collection. Hence, crossbreeding with genetically distinct cultivars could enhance the gene pool's genetic diversity and facilitate superior cultivar development
High-Density Genetic Linkage Mapping of Lepidium Based on Genotyping-by-Sequencing SNPs and Segregating Contig Tag Haplotypes
Get PDFLepidium campestre has been targeted for domestication as future oilseed and catch crop. Three hundred eighty plants comprising genotypes of L. campestre, Lepidium heterophyllum, and their interspecific F2 mapping population were genotyped using genotyping by sequencing (GBS), and the generated polymorphic markers were used for the construction of high-density genetic linkage map. TASSEL-GBS, a reference genome-based pipeline, was used for this analysis using a draft L. campestre whole genome sequence. The analysis resulted in 120,438 biallelic single-nucleotide polymorphisms (SNPs) with minor allele frequency (MAF) above 0.01. The construction of genetic linkage map was conducted using MSTMap based on phased SNPs segregating in 1:2:1 ratio for the F2 individuals, followed by genetic mapping of segregating contig tag haplotypes as dominant markers against the linkage map. The final linkage map consisted of eight linkage groups (LGs) containing 2,330 SNP markers and spanned 881 Kosambi cM. Contigs (10,302) were genetically mapped to the eight LGs, which were assembled into pseudomolecules that covered a total of ∼120.6 Mbp. The final size of the pseudomolecules ranged from 9.4 Mbp (LG-4) to 20.4 Mpb (LG-7). The following major correspondence between the eight Lepidium LGs (LG-1 to LG-8) and the five Arabidopsis thaliana (At) chromosomes (Atx-1–Atx-5) was revealed through comparative genomics analysis: LG-1&2_Atx-1, LG-3_Atx-2&3, LG-4_Atx-2, LG-5_Atx-2&Atx-3, LG-6_Atx-4&5, LG-7_Atx-4, and LG-8_Atx-5. This analysis revealed that at least 66% of the sequences of the LGs showed high collinearity with At chromosomes. The sequence identity between the corresponding regions of the LGs and At chromosomes ranged from 80.6% (LG-6) to 86.4% (LG-8) with overall mean of 82.9%. The map positions on Lepidium LGs of the homologs of 24 genes that regulate various traits in A. thaliana were also identified. The eight LGs revealed in this study confirm the previously reported (1) haploid chromosome number of eight in L. campestre and L. heterophyllum and (2) chromosomal fusion, translocation, and inversion events during the evolution of n = 8 karyotype in ancestral species shared by Lepidium and Arabidopsis to n = 5 karyotype in A. thaliana. This study generated highly useful genomic tools and resources for Lepidium that can be used to accelerate its domestication
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