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Tomato is one of the most popular vegetables grown throughout the world in general and in Ethiopia in particular. Production of the crop is constrained by different diseases and the disease caused by the early blight pathogen, Alternaria solani, is among the major ones. Early blight has been considered as commonly occurring and causing a significant economic impact on the yield and quality of the crops. Major tomato diseases in general and early blight, in particular, could be best managed by integrating a number of control practices and the application of fungicides. The application of fungicides is the most convenient and predominant way for disease control in the absence of resistant varieties. The present study was conducted to evaluate the efficacy of some selected fungicides with the objectives to assess in vitro efficacy of fungicides on the growth and sensitivity of pathogens, in vitro tolerance of pathogens to fungicides, and their effectiveness as potential foliar sprays against A. solani. A. solani was isolated from tomatoes showing typical early blight symptoms. Five fungicides viz. URGI 75% WP, Carbancholar 50%, Orozole 25 EC, Agro Laxyl MZ 63.5 WP, and Mancodex Super 72 WP were tested against the pathogen using poisoned food technique. The highest percentage reduction in the growth of A. solani was recorded with Orozole 25 EC followed by Agro Laxyl MZ 63.5 WP resulting in 100% and 56.5% inhibition in mycelial growth respectively. On the other hand, Carbancholar 50% was found the least effective in reducing the mycelial growth of A. Solani. Fungicides that showed better in vitro efficacy could be further tested for their efficacies under field conditions and can be verified for economic validity. The study also showed the potential effectiveness of fungicides for the management of early blight on tomatoes.

GWAS analysis revealed variations at loci harboring seed storage, late embryogenesis abundant protein, and a tannin biosynthesis gene associated with sorghum grain mold resistance. Grain mold is the most important disease of sorghum [Sorghum bicolor (L.) Moench]. It starts at the early stages of grain development due to concurrent infection by multiple fungal species. The genetic architecture of resistance to grain mold is poorly understood. Using a diverse set of 635 Ethiopian sorghum accessions, we conducted a multi-stage disease rating for resistance to grain mold under natural infestation in the field. Through genome-wide association analyses with 173,666 SNPs and multiple models, two novel loci were identified that were consistently associated with grain mold resistance across environments. Sequence variation at new loci containing sorghum KAFIRIN gene encoding a seed storage protein affecting seed texture and LATE EMBRYOGENESIS ABUNDANT 3 (LEA3) gene encoding a protein that accumulates in seeds, previously implicated in stress tolerance, were significantly associated with grain mold resistance. The KAFIRIN and LEA3 loci were also significant factors in grain mold resistance in accessions with non-pigmented grains. Moreover, we consistently detected the known SNP (S4_62316425) in TAN1 gene, a regulator of tannin accumulation in sorghum grain to be significantly associated with grain mold resistance. Identification of loci associated with new mechanisms of resistance provides fresh insight into genetic control of the trait, while the highly resistant accessions can serve as sources of resistance genes for breeding. Overall, our association data suggest the critical role of loci harboring seed protein genes and implicate grain chemical and physical properties in sorghum grain mold resistance.

Angular leaf spot caused by Phaeoisariopsis griseola is one of the most destructive diseases on common bean in Southern and Southwestern parts of Ethiopia. However, systematic and focus studies were lacking to this important disease. Therefore, greenhouse study was conducted to test aggressiveness of P. griseola isolates and evaluate resistance reactions of bean varieties to pathogenic isolates. 55 leaf samples were collected and seven isolates were recovered, but three isolates namely Dolla1, Dolla2 and Dorebafano1 were successfully multiplied and tested to evaluate their pathogenicity and aggressiveness on susceptible variety Dinknesh. Dolla1 and Dolla2 isolates were collected from Bolloso Sore district, while Dorebafano was from Hawassa Zuria. 21 days old plants were inoculated with spore concentration of 2 × 104 conidia ml-1. The study was factorial arranged in a completely randomized design in four replications. All tested isolates were found aggressive to susceptible check with PSI value ranging from 83.34 to 93.52%. 75% of tested varieties showed susceptible reaction to isolates, but overall aggressiveness was higher on varieties Dimtu, Babile, KATB1, KATB69 and Dinknesh. PSI values ranged from 87.96 to 100% in most varieties. The apparent infection rate was faster on susceptible varieties. The disease progress curve attained sigmoid shape in most varieties. Varieties SER125, SER119 and Nasir were identified as a good source of resistant gene to develop ALS resistance. However, further studies on identification of genes and genetic diversity of the pathogen should capture research priority. Varieties evaluated under greenhouse conditions should also be tested under field conditions. Key words: Aggressiveness, angular leaf spot, common bean, incidence, reaction, severity.

Understanding population genetic structure and diversity of a crop is essential in designing selection strategies in plant breeding. About 2010 Ethiopian sorghum accessions were phenotyped for different traits at multiple locations. A subset of the collection, 1628 accessions, predominantly landraces, some improved varieties, and inbred lines were genotyped by sequencing. Phenotypic data revealed association of important traits with different sorghum growing agro‐climatic regions, high genetic diversity and the presence of rare natural variation in the Ethiopian sorghum germplasm. Subsequent genotypic analysis determined optimum number of sub‐populations, distinct cluster groups and ancestries of each sorghum accessions. To improve utilization of germplasm, a core subset of 387 lines were selected following posteriori grouping of genotypes based on cluster groups obtained through GBS analysis followed by stratified random sampling using quantitative traits. In order to evaluate how well this new sorghum and millet innovation lab (SMIL) collection from Ethiopia is represented within the largest world sorghum collection at United States Department of Agriculture ‐ National Plant Germplasm System (USDA‐NPGS) and the sorghum association panel (SAP), comparisons were conducted based on SNP data. The SMIL collection displayed high genetic diversity with some redundancy with the USDA‐NPGS germplasm but SAP showed clear distinction. Furthermore, genome‐environment association analysis identified candidate genes associated with adaptation to abiotic factors, that will be important for exploitation of adaptive potential to different environments. In summary, our results described the diversity and relationship of sorghum collections, representativeness of developed core and provide novel insights into candidate genes associated to abiotic stress tolerance.

Grain mold, caused by a consortium of pathogenic fungal species, is the most important disease of sorghum [Sorghum bicolor (L.) Moench]. Genome wide association study on 1425 diverse Ethiopian sorghum landraces identified a major grain mold resistance locus containing tightly linked and sequence related MYB transcription factor genes. The locus contains YELLOW SEED1 (Y1), a likely non-functional pseudo gene (Y2), and YELLOW SEED3 (Y3). SNPs and other sequence polymorphisms that alter the Y1 and Y3 genes correlated with susceptibility to grain mold and provided a strong genetic evidence. Accordingly, the expression of both Y1 and Y3 genes in the developing grain and glumes of a widely known susceptible sorghum line, RTx430, were severely reduced but significantly increased in the resistant line, RTx2911. In addition, the expression of flavonoid biosynthesis genes such as DIHYDROFLAVONOL 4-REDUCTASE 3 (DFR3) was significantly induced in the resistant line in response to inoculation by a mixture of spores from different molding fungi while the susceptible line displayed reduced expression. The data suggest that the MYB genes and their grain and glume specific expressions may determine the differential regulation of the flavonoid biosynthesis pathway genes, the synthesis of 3-Deoxyanthocynidins and ultimately responses to molding fungi. The study also suggested that resistance to grain mold may be negatively associated with grain functionality traits such as ‘injera’ making quality of sorghum.

Survival of Ralstonia solanacearum in a environment or ecosystem depends on many factors, such as the race or strain of the pathogen, physical, chemical, biological soil factors and presence or absence of a host and non-hosts plants. The objectives of this study were to assess the effect of one and two season rotation sequences on the development of tomato bacterial wilt; and the survival ability of R. solanacearum in the rhizosphere and roots of presumable hosts and non-host crops in Ethiopia. A one season crop rotation involving tomato- maize-tomato, tomato- common beans -tomato and two season rotations consisting of tomato - maize- common bean-tomato, tomato –common beans – maize-tomato and tomato – tomato- tomato were established at Melkassa in Ethiopia. The effect of the system was evaluated on bacterial wilt of tomato under field conditions using a susceptible tomato cultivar (Marglobe). In one season rotation treatment involving common bean and maize after tomato resulted in a reduction of an average 6% and 16% final wilt incidence, respectively. Similarly, in the two seasons rotation sequence growing tomato after bean-maize and maize-bean resulted in about 29% average final wilt incidence reduction. The onset of wilt incidence was also delayed by one week in the two season rotations with common bean and maize compared to continues tomato growing and one season rotation with non-host crops. Survival of ability of R. solanacearum, strain designated as TomNa3 biovar 1 race 1 was studied under soil rhizosphere and roots of presumably non-host and hosts of different crops under glasshouse conditions. The pathogen was detected in rhizosphere soils and roots of presumable non-host and hosts for the pathogen after 120 days after inoculation. The population of bacterial pathogens was recorded in a declining trend but detectable in the rhizosphere soils and roots of presumable non-host crops at 30, 45, 60, 90 and 120 days after inoculation.

Bacterial wilt caused by Ralstonia solanacearum is one of the most devastating plant diseases of economically important crops mainly Solanaceous family such as tomato, potato, pepper and eggplant. These crops play a significant role primarily as sources of income and food security for the small scale farming community in Ethiopia. The occurrence of bacterial wilt disease in Ethiopia was reported in 1956 and is known to cause significant yield loss on different Solanaceous crops in different parts of the country. On the basis of conventional characterization and classification, the strains of R. solanacearum found in Ethiopia have been identified as biovar 1 and 2. Recent characterization of R. solanacearum strains based on phylotype grouping using multiplex PCR and partial endoglucanase gene sequencing identified the occurrences of phylotype II and III. The association of biovar and phylotyping schemes indicated that phylotype II comprises only biovar 2, and phylotype III comprises strains of biovar 1 and biovar 2. The importance of the disease on Solanaceous crop is increasing from time to time specially in potato producing areas of the country. Apart from Solanaceous crops, the disease has also been posing a catastrophic damage to ginger production. Latently infected ginger rhizomes and potato seed tuber and decreasing of land holdings that limit crop rotation have contributed to the wider spread of the disease. In this review attempt has been made to summarize relevant scientific studies on this economically important disease in Ethiopia as well as its different disease management options, challenges and future considerations. Because, there is no single effective control measure against the target pathogen so far, a well-coordinated effort is required to develop an integrated disease management program that will help to minimize the damage and yield loss caused by the disease.

Background\ud Post-partum haemorrhage is the leading cause of maternal death worldwide. Early administration of tranexamic acid reduces deaths due to bleeding in trauma patients. We aimed to assess the effects of early administration of tranexamic acid on death, hysterectomy, and other relevant outcomes in women with post-partum haemorrhage.\ud \ud Methods\ud In this randomised, double-blind, placebo-controlled trial, we recruited women aged 16 years and older with a clinical diagnosis of post-partum haemorrhage after a vaginal birth or caesarean section from 193 hospitals in 21 countries. We randomly assigned women to receive either 1 g intravenous tranexamic acid or matching placebo in addition to usual care. If bleeding continued after 30 min, or stopped and restarted within 24 h of the first dose, a second dose of 1 g of tranexamic acid or placebo could be given. Patients were assigned by selection of a numbered treatment pack from a box containing eight numbered packs that were identical apart from the pack number. Participants, care givers, and those assessing outcomes were masked to allocation. We originally planned to enrol 15 000 women with a composite primary endpoint of death from all-causes or hysterectomy within 42 days of giving birth. However, during the trial it became apparent that the decision to conduct a hysterectomy was often made at the same time as randomisation. Although tranexamic acid could influence the risk of death in these cases, it could not affect the risk of hysterectomy. We therefore increased the sample size from 15 000 to 20 000 women in order to estimate the effect of tranexamic acid on the risk of death from post-partum haemorrhage. All analyses were done on an intention-to-treat basis. This trial is registered with ISRCTN76912190 (Dec 8, 2008); ClinicalTrials.gov, number NCT00872469; and PACTR201007000192283.\ud \ud Findings\ud Between March, 2010, and April, 2016, 20 060 women were enrolled and randomly assigned to receive tranexamic acid (n=10 051) or placebo (n=10 009), of whom 10 036 and 9985, respectively, were included in the analysis. Death due to bleeding was significantly reduced in women given tranexamic acid (155 [1·5%] of 10 036 patients vs 191 [1·9%] of 9985 in the placebo group, risk ratio [RR] 0·81, 95% CI 0·65–1·00; p=0·045), especially in women given treatment within 3 h of giving birth (89 [1·2%] in the tranexamic acid group vs 127 [1·7%] in the placebo group, RR 0·69, 95% CI 0·52–0·91; p=0·008). All other causes of death did not differ significantly by group. Hysterectomy was not reduced with tranexamic acid (358 [3·6%] patients in the tranexamic acid group vs 351 [3·5%] in the placebo group, RR 1·02, 95% CI 0·88–1·07; p=0·84). The composite primary endpoint of death from all causes or hysterectomy was not reduced with tranexamic acid (534 [5·3%] deaths or hysterectomies in the tranexamic acid group vs 546 [5·5%] in the placebo group, RR 0·97, 95% CI 0·87-1·09; p=0·65). Adverse events (including thromboembolic events) did not differ significantly in the tranexamic acid versus placebo group.\ud \ud Interpretation\ud Tranexamic acid reduces death due to bleeding in women with post-partum haemorrhage with no adverse effects. When used as a treatment for postpartum haemorrhage, tranexamic acid should be given as soon as possible after bleeding onset.\ud \ud Funding\ud London School of Hygiene & Tropical Medicine, Pfizer, UK Department of Health, Wellcome Trust, and Bill & Melinda Gates Foundation.

The eastern Africa region, Ethiopia and its surroundings, is considered as the center of origin and diversity for sorghum, and has contributed to global sorghum genetic improvement. The germplasm from this region harbors enormous genetic variation for various traits but little is known regarding the genetic architecture of most traits. Here, 1425 Ethiopian landrace accessions were phenotyped under field conditions for presence or absence of awns, panicle compactness and shape, panicle exsertion, pericarp color, glume cover, plant height and smut resistance under diverse environmental conditions in Ethiopia. In addition, F1 hybrids obtained from a subset of 1341 accessions crossed to an A1 cytoplasmic male sterile line, ATx623, were scored for fertility/sterility reactions. Subsequently, genotyping-by-sequencing generated a total of 879,407 SNPs from which 72,190 robust SNP markers were selected after stringent quality control (QC). Pairwise distance-based hierarchical clustering identified 11 distinct groups. Of the genotypes assigned to either one of the 11 sub-populations, 65% had high ancestry membership coefficient with the likelihood of more than 0.60 and the remaining 35% represented highly admixed accessions. A genome-wide association study (GWAS) identified loci and SNPs associated with aforementioned traits. GWAS based on compressed mixed linear model (CMLM) identified SNPs with significant association (FDR ≤ 0.05) to the different traits studied. The percentage of total phenotypic variation explained with significant SNPs across traits ranged from 2 to 43%. Candidate genes showing significant association with different traits were identified. The sorghum bHLH transcription factor, ABORTED MICROSPORES was identified as a strong candidate gene conditioning male fertility. Notably, sorghum CLAVATA1 receptor like kinase, known for regulation of plant growth, and the ETHYLENE RESPONSIVE TRANSCRIPTION FACTOR gene RAP2-7, known to suppress transition to flowering, were significantly associated with plant height. In addition, the YELLOW SEED1 like MYB transcription factor and TANNIN1 showed strong association with pericarp color validating previous observations. Overall, the genetic architecture of natural variation representing the complex Ethiopian sorghum germplasm was established. The study contributes to the characterization of genes and alleles controlling agronomic traits, and will serve as a source of markers for molecular breeding.

Fifty-four hot pepper germplasm (49 local accessions and 5 AVRDC genotypes) were evaluated for resistance to fusarium wilt in a greenhouse at Melkassa Agricultural Research Centre in Ethiopia. A completely randomized design with three replications was used. Each local accession was also analyzed for associated quality traits of capsaicin and oleoresin content. The overall results indicated that disease incidence ranged from 8 (PBC-731) to 100% for Acc-15. Most local collections exhibited higher disease incidences percent than AVRDC genotypes with an overall mean DI 60%. Based on severity rating (1-5 scale), two accessions (Acc-39 and PBC-731) were highly resistant to wilt with severity ratings of 1 and 14 accessions were found resistant with severity rating scale of 2 whereas 38 accessions were susceptible with severity scale of >3. Capsaicin content percentage ranged from 0.16-0.55%, and heat unit ranged 26372 to 88775 SHU, for Acc-32 and Acc-24, respectively. Oleoresin content in international color unit and ASTA value ranged from 32,800 to 118,840 cu and 82-296 ASTA with an overall mean of 69,704 ICU and 172 ASTA value. The highest color quality colors of greater than 250 ASTA was exhibited by 10 accessions (Acc-4, Acc-5, Acc-6, Acc-7, Acc-24, Acc-27, Acc-33, Acc-34, Acc-39 and Acc-31). This study identified resistance accessions with desirable qualities among the 49 local accessions. These materials also had good wilt resistance potential and could be used as source parents in the future hybridization and for simultaneous selection for Fusarium wilt resistance and high processing quality traits in hot pepper improvement program.

Field experiments were conducted in Ethiopia to evaluate the effect of silicon fertilizer and sugarcane bagasse on tomato bacterial wilt (Ralstonia solanacearum). Silicon fertilizer significantly reduced the bacterial population, mean wilt incidence, percent severity index, and corresponding areas of disease incidence, and severity progress curves in the moderately resistant tomato cultivar (King Kong 2). Similarly, sugarcane bagasse resulted in a significant reduction of mean wilt and percent severity index, the corresponding areas under disease incidence and severity progress curves and the bacterial population at 5 days post inoculation, compared to the control, in cultivar King Kong 2. However, neither silicon fertilizer nor sugarcane bagasse resulted in any significant reduction of all disease parameters in the moderately susceptible cultivar Marglobe. Silicon fertilizer and sugarcane bagasse amend- ments also increased fruit yield for cultivar King Kong 2, but not for cultivar Marglobe. The total silicon content was also significantly increased in silicon fertilizer amendment, followed by sugarcane bagasse amended plants. The study recommends use of silicon fertil- izer as a soil amendment under field conditions to augment resistance in moderately resistant cultivars where bacterial wilt disease problems prevail. However, a silicon fertilizer or silicon source was not found to substantiate or improve a susceptible cultivar. Sugar- cane bagasse was demonstrated to possess a potential as an alternative soil amendment material and as an alternative silicon source.