Urban Homegarden for Woody Species Conservation and Carbon Sequestration: The Case of Jimma City, Southwest Ethiopia

Homegardens in urban are found to be an important refuge for native biodiversity and provide huge contribution for climate change mitigation. The study was undertaken to investigate potential of homegarden in conservation of woody species and carbon sequestration in Jimma City. A complete listing of woody species within 138 homegardens and 39 sample plot size 10m×10m (100m2) were surveyed. Diameter at breast) height and the height of the tree were measured. Shannon diversity and Jaccard coefficient of similarity index were used to determine the species composition. Allometric equation was used to estimate aboveground carbon stocks of woody species. A total of 40 woody species (36 in homegarden and 22 in government institution) belonging to 24 families were recorded. Very significantly higher (P<0.001) species richness and diversity were observed in homegardens. But no significant difference was observed (p>0.5) among homegardens in three kebeles. Jaccard coefficient of similarity index (47.5%) showed low similarity in woody composition between two systems. About 2,877.13Mgha-1(884.2 Mgha-1 in homegarden &1,992.95Mgha -1 in government institution) carbon of about 319.57Mg of CO2 equivalents were measured. Very highly significant (p<0.001) and non-significant difference (p>0.05) in carbon storage were observed between systems and among homegardens respectively. The result reveled homegardens in Jimma city have good potential for biodiversity conservation and climate change mitigation. Hence, responsible bodies need to consider the role of homegarden in maintaining native biodiversity and climate change mitigation in urban development planning. Keywords: Biodiversity conservation, government institution compound, carbon stock, climate change mitigation. DOI: 10.7176/JNSR/9-13-02 Publication date:July 31st 201

International Policies and Conventions on International Rivers and the Rights of Ethiopia to Construct Dam on Nile River: The Case of the Great Renaissance Dam of Ethiopia

Sustainable transboundary water resources managements are challenged by water governance problem. Equitable and reasonable use of water resources shared by co-basin countries requires reliable common agreements. International water laws such as UN Watercourses (1997), Helsinki Rules (1966) have provided vital legal instruments for effective management and negotiation over international water courses. However, Nile River use and development has challenged for last several decades due to discriminatory bilateral agreements made during colonial periods. The Cooperative Framework Agreement (CFA) provided to achieve equitable use of Nile River and promote regional socioeconomic development is important step advancing to stop unfair water allocation and claim in the region. The enduring claim over water share and use by Egypt and Sudan referring colonial era agreements are unacceptable because they denied legal and natural rights of the upstream countries as well as opposed international water law. With this respect, Ethiopia has natural and legal right to construct Great Ethiopian Renaissance Dam. The downstream countries (Egypt and Sudan) should ratify CFA and respect international water laws. Therefore, mutually acceptable cooperative commitment amongst the riparian states of the Nile basin is the only necessary condition for promoting sustainable use and development Nile River as well as achieving peace and security in the Nile river basin. Keywords: UN Watercourses, Helsinki Rules, Nile River basin, downstream countries, international water law principles DOI: 10.7176/IAGS/83-02 Publication date:June 30th 202

Agroforestry: A Supplementary Tool for Biodiversity Conservation and Climate Change Mitigation and Adaptation

Biodiversity loss and climate change are the major global problems threating livelihoods in developing countries. Agroforestry as an integrated land use system has been proved to reduce these problems. However, contributions of agroforestry for conservation of flora and fauna biodiversity and reduction climate change impacts faced empirical evidence. This paper aimed to provide empirical information on role of agroforestry for conservation of flora and fauna biodiversity and climate change mitigation and adaptation. The result reveled that agroforestry has played a greater role for conservation of fauna and native flora diversity and mitigation of CO2 than monocroping and open cereal based agriculture but less than natural forest. The tree components of agroforestry are important for biodiversity conservation, CO2 sequestration and climate change adaptation. CO2 sequestration through above and ground biomass, offsetting CO2 emission from deforestation and microclimate modification are major climate change mitigation effect. Provision of numerous ecosystem services such as food, fodder and fuel wood, income source, enhancing soil productivity, protecting pest and increased resistance to diseases help community to sustain changing climate effects.. Hence, considerable attentions need to be given to agroforestry to contribute considerable benefit in conservation of biodiversity, and climate change mitigation and adaptation next to forest. Keywords:  Agroforestry, flora and fauna diversity, mitigation of CO2, ecosystem services. DOI: 10.7176/JNSR/9-19-07 Publication date:October 31st 201

Phenotypic Variability, Heritability and Associations of Agronomic and Quality Traits in Cultivated Ethiopian Durum Wheat (Triticum turgidum L. ssp. Durum, Desf.)

Quality is an important aspect of durum wheat in the processing sector. Thus, recognizing the variability of quality and agronomic traits and their association is fundamental in designing plant breeding programs. This study aimed to assess the variability, heritability, genetic advance, and correlation of some agronomic and quality traits among 420 Ethiopian durum wheat genotypes and to identify the promising genotypes with distinct processing quality attributes to produce superior quality pasta. The field experiment was conducted at two locations (Sinana and Chefe Donsa) using an alpha lattice design with two replications. Analysis of variance, chi-square test, and Shannon-Weaver diversity index revealed the existence of highly significant (p < 0.001) variation among genotypes for all studied traits. The broad-sense heritability values were ranging from 46.2% (days to maturity) to 81% (thousand kernel weight) with the genetic advance as a percent of the mean ranging from 1.1% (days to maturity) to 21.2% (grain yield). The phenotypic correlation coefficients for all possible pairs of quantitative traits showed a significant (p < 0.05) association among most paired traits. The gluten content (GC) and grain protein content (GPC) were negatively correlated with grain yield and yield-related traits and positively associated with phenological traits, while yield and phenological traits correlated negatively. The frequency distributions of amber-colored and vitreous kernels, which are preferable characters of durum wheat in processing, were highly dominant in Ethiopian durum wheat genotypes. The identified top 5% genotypes, which have amber color and vitreous kernel with high GC and GPC content as well as sufficient grain yield, could be directly used by the processing sector and/or as donors of alleles in durum wheat breeding programs

Novel Expressed Sequence Tag-Derived and Other Genomic Simple Sequence Repeat Markers Revealed Genetic Diversity in Ethiopian Finger Millet Landrace Populations and Cultivars

Finger millet (Eleusine coracana (L.) Geartn.) is a self-pollinating amphidiploid crop cultivated with minimal input for food and feed, as well as a source of income for small-scale farmers. To efficiently assess its genetic diversity for conservation and use in breeding programs, polymorphic DNA markers that represent its complex tetraploid genome have to be developed and used. In this study, 13 new expressed sequence tag-derived simple sequence repeat (EST-SSR) markers were developed based on publicly available finger millet ESTs. Using 10 polymorphic SSR markers (3 genomic and 7 novel EST-derived), the genetic diversity of 55 landrace accessions and 5 cultivars of finger millet representing its major growing areas in Ethiopia was assessed. In total, 26 alleles were detected across the 10 loci, and the average observed number of alleles per locus was 5.6. The polymorphic information content (PIC) of the loci ranged from 0.045 (Elco-48) to 0.71 (UGEP-66). The level of genetic diversity did not differ much between the accessions with the mean gene diversity estimates ranging only from 0.44 (accession 216054) to 0.68 (accession 237443). Similarly, a narrow range of variation was recorded at the level of regional states ranging from 0.54 (Oromia) to 0.59 (Amhara and Tigray). Interestingly, the average gene diversity of the landrace accessions (0.57) was similar to that of the cultivars (0.58). The analysis of molecular variance (AMOVA) revealed significant genetic variation both within and among accessions. The variation among the accessions accounted for 18.8% of the total variation (FST = 0.19; P < 0.001). Similarly, significant genetic variation was obtained among the geographic regions, accounting for 6.9% of the total variation (P < 0.001). The results of the cluster, principal coordinate, and population structure analyses suggest a poor correlation between the genetic makeups of finger millet landrace populations and their geographic regions of origin, which in turn suggests strong gene flow between populations within and across geographic regions. This study contributed novel EST-SSR markers for their various applications, and those that were monomorphic should be tested in more diverse finger millet genetic resources

Hydroponic optimization and screening of aluminum tolerance on finger millet (Eleusine coracana (L.) Gaertn.) accessions and cultivars

Finger millet (Eleusine coracana (L.) Gaertn.) is an annual allotetraploid that belongs to the grass family Poaceae subfamily Chloridoideae. Using less productive cultivars, biotic and abiotic stresses affect the yield and productivity of finger millet in Ethiopia. This research was aimed at investigating the acidity/Al tolerance of 328 finger millet accessions and 15 cultivars from Ethiopia and Zimbabwe. Prior to screening the accessions, optimization was performed on 15 cultivars and 15 accessions under three Al concentrations (0, 75, and 100 µM), and, afterward, 100 µM of Al concentration was selected as the threshold level. Root length (RL) and shoot length (SL) were recorded after 10 days of treatment. Accessions 215836, 215845, and 229722 and cultivars Urji, Bareda, and Axum were found Al-tolerant, while cultivars Tadesse, Padet, and Kumsa and accessions 212462, 215804, and 238323 were found Al-susceptible. ANOVA on RL indicated that the variance due to environment (42.3) was higher than genotypic variance (0.37). Whereas, the ANOVA on SL indicated the variance due to environment was not significant, and genotypic variance (0.18) was higher than environmental (0.02). RL was highly affected due to Al stress, while no distinct and visible symptoms were observed on SL. Furthermore, the screening of 328 accessions under 100 µM and the control resulted in Al-tolerant (n = 20), intermediate (225), and Al-susceptible (83). The results of the present study reveal that the presence of acid-tolerant accessions can be used as inputs for breeders to improve the productivity of finger millet in acidic areas

Analyses of genetic diversity and population structure of anchote (Coccinia abyssinica (Lam.) Cogn.) using newly developed EST-SSR markers

Anchote (Coccinia abyssinica (Lam.) Cogn.) is a perennial root crop belonging to Cucurbitaceae family. It is endemic to Ethiopia and distributed over wide range of agro-ecologies. For further improvement and efficient conservation of this crop, characterization of its genetic diversity and its pattern of distribution is a vitally important step. Expressed sequence tags-simple sequence repeats (EST-SSRs) markers were developed from publicly available watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] ESTs in the GenBank database. Among those novel markers, eight were polymorphic and subsequently used for genetic diversity and population structure analyses of 30 anchote accessions collected from western Ethiopia. A total of 24 alleles were obtained across the eight polymorphic loci and 30 accessions that revealed moderate level of genetic diversity in this minor crop. Among the eight loci, locus CA_06 was the most informative with six alleles and polymorphic information content (PIC) of 0.76. The accessions showed about threefold variation in terms of genetic diversity, with expected heterozygosity (He) ranging from 0.15 (accession An) to 0.44 (accession Dg). Other accessions with higher genetic diversity include Ar and Gu (He = 0.43 and 0.41, respectively). Analysis of molecular variance (AMOVA) revealed that the variation within accessions and among accessions accounted for 84.7% and 15.3% of the total variation, respectively. The study revealed low but significant population differentiation in this crop with no clear pattern of population structure. The EST-SSR markers developed in this study are the first of their kind for anchote and can be used for characterization of its wider genetic resources for conservation and breeding purposes

Genetic Diversity of Durum Wheat (Triticum turgidum L. ssp. durum, Desf) Germplasm as Revealed by Morphological and SSR Markers

Ethiopia is considered a center of origin and diversity for durum wheat and is endowed with many diverse landraces. This research aimed to estimate the extent and pattern of genetic diversity in Ethiopian durum wheat germplasm. Thus, 104 durum wheat genotypes representing thirteen populations, three regions, and four altitudinal classes were investigated for their genetic diversity, using 10 grain quality- and grain yield-related phenotypic traits and 14 simple sequence repeat (SSR) makers. The analysis of the phenotypic traits revealed a high mean Shannon diversity index (H′ = 0.78) among the genotypes and indicated a high level of phenotypic variation. The principal component analysis (PCA) classified the genotypes into three groups. The SSR markers showed a high mean value of polymorphic information content (PIC = 0.50) and gene diversity (h = 0.56), and a moderate number of alleles per locus (Na = 4). Analysis of molecular variance (AMOVA) revealed a high level of variation within populations, regions, and altitudinal classes, accounting for 88%, 97%, and 97% of the total variation, respectively. Pairwise genetic differentiation and Nei’s genetic distance analyses identified that the cultivars are distinct from the landrace populations. The distance-based (Discriminant Analysis of Principal Component (DAPC) and Minimum Spanning Network (MSN)) and model-based population stratification (STRUCTURE) methods of clustering grouped the genotypes into two clusters. Both the phenotypic data-based PCA and the molecular data-based DAPC and MSN analyses defined distinct groupings of cultivars and landraces. The phenotypic and molecular diversity analyses highlighted the high genetic variation in the Ethiopian durum wheat gene pool. The investigated SSRs showed significant associations with one or more target phenotypic traits. The markers identify landraces with high grain yield and quality traits. This study highlights the usefulness of Ethiopian landraces for cultivar development, contributing to food security in the region and beyond

New transcriptome-based SNP markers for noug (Guizotia abyssinica) and their conversion to KASP markers for population genetics analyses

The development and use of genomic resources are essential for understanding the population genetics of crops for their efficient conservation and enhancement. Noug (Guizotia abyssinica) is an economically important oilseed crop in Ethiopia and India. The present study sought to develop new DNA markers for this crop. Transcriptome sequencing was conducted on two genotypes and 628 transcript sequences containing 959 single nucleotide polymorphisms (SNPs) were developed. A competitive allele-specific PCR (KASP) assay was developed for the SNPs and used for genotyping of 24 accessions. A total of 554 loci were successfully genotyped across the accessions, and 202 polymorphic loci were used for population genetics analyses. Polymorphism information content (PIC) of the loci varied from 0.01 to 0.37 with a mean of 0.24, and about 49% of the loci showed significant deviation from the Hardy-Weinberg equilibrium. The mean expected heterozygosity was 0.27 suggesting moderately high genetic variation within accessions. Low but significant differentiation existed among accessions (FST = 0.045, p &lt; 0.0001). Landrace populations from isolated areas may have useful mutations and should be conserved and used in breeding this crop. The genomic resources developed in this study were shown to be useful for population genetics research and can also be used in, e.g., association genetics

Genotype by environment interaction, correlation, AMMI, GGE biplot and cluster analysis for grain yield and other agronomic traits in sorghum (Sorghum bicolor L. Moench)

Genotype by environment (GxE) interaction is a major factor limiting the success of germplasm selection and identification of superior genotypes for use in plant breeding programs. Similar to the case in other crops, GxE complicates the improvement of sorghum, and hence it should be determined and used in decision-making programs. The present study aimed at assessing the GxE interaction, and the correlation between traits for superior sorghum genotypes. Three hundred twenty sorghum landraces and four improved varieties were used in alpha lattice experimental design-based field trial across three environments (Melkassa, Mieso and Mehoni) in Ethiopia. Phenotypic data were collected for days to flowering (DTF), plant height (PH), panicle length (PALH), panicle width (PAWD), panicle weight (PAWT) and grain yield (GY). The results revealed that the variance due to genotype, environment and GxE interaction were highly significant (P < 0.001) for all traits. GY and PAWT were highly affected by environments and GxE whereas DTF, PALH, PAWD and PH were mainly affected by genotypic variation. Therefore, multi-environment testing is needed for taking care of G x E interaction to identify high yielding and stable sorghum landraces. GY and PAWT revealed highly significant positive correlations indicating the possibility of effective selection of the two traits simultaneously. Among the studied populations, South Wello, West Hararghe and Shewa zones had highly diverse genotypes that were distributed across all clusters. Hence, these areas can be considered as hotspots for identifying divergent sorghum landraces that could be used in breeding programs. Melkassa was the most representative environment whereas Mieso was the most discriminating. Five genotypes (G148, G123, G110, G203 and G73) were identified as superior across the test environments for grain yield with farmer-preferred trait, such as plant height. The identified stable and high yielding genotypes are valuable genetic resources that should be used in sorghum breeding programs