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Angular Leaf Spot (ALS) caused by Pseudocercospora griseola is responsible for 54% yield loss in Uganda's common beans. Host plant resistance is a safe and cost-effective management strategy for this disease. Identification of resistant common bean genotypes to prevailing races is vital to utilize the crop. Therefore, the objective of this study was to identify genotypes that are resistant to the commonly occurring and virulent P. griseola races in Uganda for breeding purposes. Twenty-seven common bean genotypes and three control varieties (Mexico54, MCM5001, and CAL96) were screened at field conditions for ALS resistance at testing site (National Agricultural Research Laboratories - Kawanda) under natural disease infection. The genotypes were also evaluated in the screen house using frequently occurring P. griseola races: 61:63, 1:6 and 21:39. Variability in the severity of ALS on both leaves and pods was significant whereas the difference between seasons and the interaction between the seasons and genotypes was only significant for yield. The disease severity scores were higher (mean of 3.2) on leaves than on pods (mean of 2.9). Ninety-three percent, 33.3% and 15% of the genotypes were resistant to P. griseola races 21:39, 1:6 and 61:63, respectively. A large-seeded genotype AFR703 was resistant to all the three P. griseola races. A medium seed size genotype AFR702 and three small seed genotypes (G148, G18842 and G6727) were resistant to both 21:39 and 1:6 but moderate resistance to 61:63 whereas a large-seeded genotype AND279 was resistant to both 61:63 and 21:39 but moderate to 1:6. All of these six genotypes (AFR703, AFR702, G148, G18842, G6727 and AND279) expressed moderate resistance to P. griseola races on leaves under field conditions. Thus, these common bean genotypes could be used as sources of ALS resistance for breeding programs to address the ALS constraint; and genes responsible for resistance have to be characterized. [ABSTRACT FROM AUTHOR]

Common bean (Phaseolus vulgaris L.) is a staple and nutritious leguminous food crop for all income categories in Africa. Efforts to improve its yield performance and nutritional components, especially iron and zinc have resulted in release of several varieties in the sub-Sahara African region. The objective of this study was to assess genetic progress in varieties released in 12 African countries through the Pan African Bean Research Alliance (PABRA) from 1973 to 2017, to inform current breeding decisions. A total of 214 released varieties, land races and breeding lines, of bush and climbing beans were evaluated for yield, micronutrient (Fe and Zn) concentration, and phenology in three locations (Kawanda and Kachwekano in Uganda, and Kitengule in Tanzania) in 2017/2018. There were significant differences (P<0.01) among genotypes for all traits, except days to maturity (DPM). Genotype x environment interaction was also significant (P<0.05) for all assessed traits, except for iron in climbing beans. Across environments, repeatability (H²) was greater than 0.50 for all traits, except for DPM in climbing beans. Annual rates of genetic yield gains were 4.41 and 4.57 kg ha-1 for large and small seed bush beans, and -2.74 and 21.6 kg ha-1 for large and small seeded climbers. Similarly, gains in seed iron (FESEED) were 0.40 and 0.17 ppm for bush and climbing beans, respectively. These represented an annual relative gain over the oldest varieties of 0.6 and 0.7% kg ha-1 for yield of large and small seeded bush beans, -0.3 and 1.6% kg ha-1 for yield of large and small seeded climbers, 0.6 and 0.2% ppm for FESEED of bush and climbers. Overall, genetic progress was slow for both yield and FESEED. [ABSTRACT FROM AUTHOR]

Root rots cause severe yield losses of up to >70% in common bean (Phaseolus vulgaris L.) in most parts of the world, with devastating effects on the major commercial bean cultivars in East and Central Africa. Increased intensity of droughts and rains, and higher temperatures influence the occurrence and distribution of root rots, resulting in increased epidemics. The causal pathogens tend to occur in a complex, and since most cultivars do not have broad resistance, adverse effects continue to occur. The objective of this study was to evaluate the levels of dual resistance of new breeding lines (BL) developed for root rot resistance, as well as Andean (ADP) genotypes, for resistance to Fusarium (FRR) and Pythium root rots (PRR). Altogether, 316 new BL developed for root rot resistance and 295 ADP bean genotypes were evaluated at Kawanda in Uganda. There were significant differences (P<0.05) among genotypes for both root rots and yield. Thirty and 1.9 percent of the BL and ADP genotypes expressed resistance to both root rots. In addition, more than 80% of ADP genotypes showed susceptibility to both root rots. Yield was generally poor with means of 458 kg ha-1 for ADP, and ranging from 949 to 1075 kg ha-1 for the BL groups. Nonetheless, the 0.3 and 2.4% of the ADP and BL that yielded >2000 kg ha-1 expressed high yield potential, considering that majority of the genotypes yielded below 1000 kg ha-1. [ABSTRACT FROM AUTHOR]

Over the last 5 years, Southern blight caused by Sclerotium rolfsii Sacc. has superseded root rots caused by pathogens such as Fusarium and Pythium spp. as a major constraint of common bean ( Phaseolus vulgaris L.) production in Uganda. Although S. rolfsii is prevalent in all bean-growing regions of Uganda, there is a lack of information about its diversity and pathogenicity to guide the development of effective management strategies. In total, 348 S. rolfsii isolates were obtained from bean fields in seven agroecological zones of Uganda, with the following objectives: to characterize their morphology, based on mycelial growth rate, mycelium texture, and number of sclerotia; and to determine the pathogenicity of 75 selected isolates on five common bean varieties in artificially inoculated soils in a screenhouse. We found that mycelial growth rate and the number of sclerotia produced on artificial media varied among agroecological zones but not within a zone. The five bean varieties tested were found to be susceptible to S. rolfsii , including varieties MLB49-89A and RWR719 that are resistant to Fusarium and Pythium root rots, respectively. Preemergence damping-off ranged between 0 and 100%, and disease severity index ranged between 4.4 and 100%. The widespread and high levels of S. rolfsii virulence on varieties of common bean indicate that management intervention is urgently required to help reduce losses incurred by Ugandan smallholder farmers.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

Background: Artemisinin-based combination therapy (ACT), the treatment of choice for uncomplicated falciparum malaria, is unaffordable and generally inaccessible in the private sector, the first port of call for most malaria treatment across rural Africa. Between August 2007 and May 2010, the Uganda Ministry of Health and the Medicines for Malaria Venture conducted the Consortium for ACT Private Sector Subsidy (CAPSS) pilot study to test whether access to ACT in the private sector could be improved through the provision of a high level supply chain subsidy., Methods: Four intervention districts were purposefully selected to receive branded subsidized medicines - "ACT with a leaf", while the fifth district acted as the control. Baseline and evaluation outlet exit surveys and retail audits were conducted at licensed and unlicensed drug outlets in the intervention and control districts. A survey-adjusted, multivariate logistic regression model was used to analyse the intervention's impact on: ACT uptake and price; purchase of ACT within 24 hours of symptom onset; ACT availability and displacement of sub-optimal anti-malarial., Results: At baseline, ACT accounted for less than 1% of anti-malarials purchased from licensed drug shops for children less than five years old. However, at evaluation, "ACT with a leaf" accounted for 69% of anti-malarial purchased in the interventions districts. Purchase of ACT within 24 hours of symptom onset for children under five years rose from 0.8% at baseline to 26.2% (95% CI: 23.2-29.2%) at evaluation in the intervention districts. In the control district, it rose modestly from 1.8% to 5.6% (95% CI: 4.0-7.3%). The odds of purchasing ACT within 24 hours in the intervention districts compared to the control was 0.46 (95% CI: 0.08-2.68, p=0.4) at baseline and significant increased to 6.11 (95% CI: 4.32-8.62, p<0.0001) at evaluation. Children less than five years of age had "ACT with a leaf" purchased for them more often than those aged above five years. There was no evidence of price gouging., Conclusions: These data demonstrate that a supply-side subsidy and an intensive communications campaign significantly increased the uptake and use of ACT in the private sector in Uganda.

Background: Home-based management of fever (HBMF) could improve prompt access to antimalarial medicines for African children. However, the perception of treatment failure by caregivers has not been assessed., Methods: Caregiver's perceived treatment outcome in HBMF and in alternative sources of fever treatment was assessed in a rural Ugandan setting using nine hundred and seventy eight (978) caregivers of children between two and 59 months of age, who had reported fever within two weeks prior to the study., Results: Lower caregivers' perceived treatment failure (15% and 23%) was observed in the formal health facilities and in HBMF, compared to private clinics (38%), drug shops (55%) or among those who used herbs (56%). Under HBMF, starting treatment within 24 hours of symptoms onset and taking treatment for the recommended three days duration was associated with a lower perceived treatment failure. Conversely, vomiting, convulsions and any illness in the month prior to the fever episode was associated with a higher perceived treatment failure., Conclusion: In this medium malaria transmission setting, caregiver's perceived treatment outcome was better in HBMF compared to alternative informal sources of treatment.