Faculty of Agriculture and Environmental Sciences

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Agricultural Cooperative marketing and credit policy reform in Uganda: An opportunity for poverty reduction
(African Journal of Food, Agriculture, Nutrition and Development, 2019) Onyilo, Francis; Adong, Annet
Academics and development practitioners increasingly view cooperatives as the cornerstone for agricultural transformation and poverty reduction in sub-Saharan Africa. Cooperatives play a crucial role in promoting bulk storage and sale by smallholder farmers, which can play a major role in poverty reduction for farmers otherwise unable to commercialize. Despite the significant role of cooperatives, the reforms associated with economic liberalisation have caused many cooperatives in the region to fail. While efforts were made in Uganda to ameliorate this situation through the passing of the National Co-operative Policy (NCP), this has done little to enhance the survival of these cooperatives. In this opinion paper, we identify challenges faced by cooperatives that negatively impact performance and survival, such political interference, lack of administrative support, human resource constraints, inadequate knowledge of the operations by members and poor governance. This paper recommends stronger linkages between the Ministry of Trade, Industry and Cooperatives and the Ministry of Agriculture Animal Industry and Fisheries (MAAIF). Integrating cooperatives into the decentralisation framework and formalising existing village savings and loan association groups into formal cooperatives. Most importantly, the government needs to take on a more proactive approach toward cooperative development, as seen in some countries such as South Africa and Rwanda.
Agrobacterium tumefaciens-mediated transformation of pseudocercospora fijiensis to determine the role of PfHog1 in osmotic stress regulation and virulence modulation
(Frontiers in Microbiology, 2017) Onyilo, Francis; Tusiime, Geoffrey; Chen, Li-Hung; Falk, Bryce; Stergiopoulos, Ioannis; Tripathi, N. Jaindra; Tushemereirwe, Wilberforce; Kubiriba, Jerome; Changa, Charles; Tripathi, Leena
Black Sigatoka disease, caused by Pseudocercospora fijiensis is a serious constraint to banana production worldwide. The disease continues to spread in new ecological niches and there is an urgent need to develop strategies for its control. The high osmolarity glycerol (HOG) pathway in Saccharomyces cerevisiae is well known to respond to changes in external osmolarity. HOG pathway activation leads to phosphorylation, activation and nuclear transduction of the HOG1 mitogen-activated protein kinases (MAPKs). The activated HOG1 triggers several responses to osmotic stress, including up or down regulation of different genes, regulation of protein translation, adjustments to cell cycle progression and synthesis of osmolyte glycerol. This study investigated the role of the MAPK-encoding PfHog1 gene on osmotic stress adaptation and virulence of P. fijiensis. RNA interference-mediated gene silencing of PfHog1 significantly suppressed growth of P. fijiensis on potato dextrose agar media supplemented with 1 M NaCl, indicating that PfHog1 regulates osmotic stress. In addition, virulence of the PfHog1-silenced mutants of P. fijiensis on banana was significantly reduced, as observed from the low rates of necrosis and disease development on the infected leaves. Staining with lacto phenol cotton blue further confirmed the impaired mycelial growth of the PfHog1 in the infected leaf tissues, which was further confirmed with quantification of the fungal biomass using absolute- quantitative PCR. Collectively, these findings demonstrate that PfHog1 plays a critical role in osmotic stress regulation and virulence of P. fijiensis on its host banana. Thus, PfHog1 could be an interesting target for the control of black Sigatoka disease in banana.
Analysis of sesame seed production and export trends; challenges and strategies towards increasing production in Uganda
(Oilseeds and fats, Crops and Lipids Journal, 2021-01) Wacal, Cosmas; Basalirwa, Daniel; Okello-Anyanga, Walter; Murongo, Marius Flarian; Namirembe, Caroline; Malingumu, Richard
Sesame (Sesamum indicum L.) is one of the most ancient oilseed crops cultivated for its edible oil and uses in food. Sesame seeds are very nutritious and confer health benefits. However, its potential production in Uganda has not been fully realized. The objective of this review was to summarize the trends in sesame production, export quantity, export value, challenges, and strategies for sustainable sesame seed production in Uganda. The review revealed the sesame seed production and area harvested generally increased from 1996 to 2007 but significantly decreased between 2008 and 2018. The review also revealed that while the export quantities and values were low, they gradually increased from 2009 to 2016. The decreased production between 2008 and 2016 could have been due to challenges such as pests and diseases, loss of soil fertility, prolonged drought, poor agronomic practices, poor yielding varieties, and lack of access to credit. Therefore, it is recommended to improve breeding programs and soil management practices; strengthen agricultural credits and extension services to support marketing of sesame seeds; and improve agronomic practices and farmer knowledge on improved techniques such as sowing methods, plant spacing, intercropping practices, pests and disease control measures. These could boost sesame production in Uganda given the high domestic and global demand for sesame seeds and provide an opportunity to expand sesame production throughout Uganda. Research should focus on how to increase seed yield on farmers’ fields and bridge the yield gap between researchers and farmers while adopting good agronomic practices.
Anodic oxidation of effluents from stages of MBR-UF Municipal landfill leachate treatment plant
(Mary Ann Liebert, 2020-05-18) Ukundimana, Zubeda; Kobya, Mehmet; Omwene, Philip Isaac; Gengec, Erhan; Can, Orhan Taner
This study used boron-doped diamond electrode on niobium substrate (Nb/boron-doped diamond [BDD]) for the anodic oxidation of landfill leachate in a batch reactor. Raw leachate and biologically pretreated effluent samples were collected from each step of the existing unit operation of a municipal landfill leachate treatment plant (Kocaeli-Turkey). The influence of parameters, such as treatment time, initial pH (3.50–10.0), and applied current density (j = 76–1,060 A/m2), on the removal of total organic carbon (TOC), chemical oxygen demand (COD), and ammonium nitrogen (NH4+-N) was assessed. The highest pollutant removal efficiencies were obtained at leachate inherent pH (6.50–8.75), moreover, pollutant removal rates increased with the increase in current density. The NH4+-N removal mainly occurred by indirect oxidation and well fitted second-order kinetics, whereas COD removal followed pseudo first-order kinetics. The optimum current density ensuring simultaneous removal of COD and NH4+-N was 756 and 455 A/m2 for raw leachate and for pretreated effluents, respectively. Under these optimums, nearly complete NH4+-N removal was attained, while ≥97% removal of TOC and COD was recorded. Herein, we present anodic oxidation as a suitable alternative for treatment of both stabilized raw leachate and effluents from stages of the membrane bioreactor/ultrafiltration treatment plant for the abatement of COD, TOC, and NH4+-N.
Batch fermentation of succinic acid from cheese whey by Actinobacillus succinogenes under variant medium composition
(Springer, 2021-07-29) Omwene, Philip Isaac; Yağcıoğlu, Meltem; Öcal-Sarihan, Zehra Betül; Ertan, Fatma; Keris-Sen, Ülker Diler; Karagunduz, Ahmet; Keskinler, Bülent
Bio-based succinic acid production has attracted global attention since its consideration as a potential replacement to petroleum-based platform chemicals. This study used three different CO2 sources, namely NaHCO3, K2CO3 and MgCO3 for fermentation of succinic acid (SA) by Actinobacillus succinogenes under three distinct substrate conditions i.e. lactose, whey and whey devoid of any supplements. Batch experiments were performed in both anaerobic flasks and 5L benchtop fermenter. SA fermentation in anaerobic flasks was unfettered by supplementary nutrients. However, fermentation in the benchtop fermenter devoid of supplementary nutrients resulted into 42% reduction in SA yield as well as lower SA productivities. Furthermore, a significant reduction of cell growth occurred in anerobic flasks at pH < 6.0, and complete termination of bacterial activity was noted at pH < 5.3. The highest SA titer, yield and productivity of 15.67 g/L, 0.54 g/g and 0.33 g/L/h, respectively, was recorded from whey fermentation with MgCO3. The present study further highlights significant inhibitory effect of K2CO3 buffered medium on Actinobacillus succinogenes. Thus, we can claim that environmental pollution as well as costs of SA production from whey can be reduced by leveraging on whey residual nutrients to support the activity of Actinobacillus succinogenes.
Bio-based succinic acid recovery by ion exchange resins integrated with nanofiltration/reverse osmosis preceded crystallization
(Elsevier, 2021-07-03) Omwenea, Philip Isaac; Sarihan, Zehra Betul Ocal; Karagunduz, Ahmet; Keskinlera, Bulen
Succinic acid is a key platform chemical for production of various products such as biodegradable polymers, pharmaceuticals, fine chemicals and foods. In the present study, bio-based succinic acid was recovered through two processes. Process I consisted of chromatographic separation with anionic exchange resin followed by direct crystallization, whereas process II sequentially consisted of cationic exchanger, activated carbon, NF/RO membrane, vacuum distillation, and crystallization. The highest chromatographic separation efficiency for succinic acid by Amberlite IRA900 Cl column was calculated as 69.3% at flow rate of 0.42 BV/h. Rejection of succinic aid (SA), lactic acid (LA), formic acid (FA) and acetic acid (AC) by NF90 membrane was 53.1, 51.8, 46.6 and 39.8%, respectively at pH less than 2. However, at pH 6.8 the respective rejections increased to 96.8, 90.6, 71.3 and 70.5%. Double pass with BW30 or HP reverse osmosis membranes achieved retention of SA, LA, FA and AC of 95.9%, 95.8%, 65.4% and 46.9%, respectively. Analysis of generated SA crystals by X-ray diffraction technique (XRD) and Fourier transform infrared (FTIR) showed the crystallinity of recovered SA as conformable to standard grade crytsals. The purity of generated succinic acid crystals was recorded as 98.5% and 96.7% for process I and process II, respectively. The calculated succinic acid yield was 78% for process I and 65% for process II. Herein, we demonstrated two alternative systems for bio-based succinic acid recovery, which will set a stage for research in efficient downstream purification of SA.
Boric acid recovery from wastewater by chromatographic separation and mathematical modeling
(Elsevier, 2024-03-04) Kole, Zehra; Ocal, Zehra Betul; Omwene, Philip Isaac; Soydemir, Gulfem; Keskinler, Bulent; Karagunduz, Ahmet
The new approaches in industrial wastewater management underscores the importance of reclaiming valuable materials. Within the boron industry, the generation of substantial wastewater containing preliminary boron species is a significant concern. This study focuses on recovering boric acid from boron production wastewater, addressing the challenge of separating impurities like sulfate, calcium, and magnesium. The methodology adopts chromatographic separation using a cation exchange resin in two forms: (1) Finex CS10GC cation exchanger in Na+ form and (2) Finex CS10GC cation exchanger in Ca2+/Mg2+ form. Notably, the Finex CS10GC ion exchanger in Na+ form achieves a separation efficiency of 95.5 % at a flow rate of 5 mL/min with a 0.20 bed volume (BV) loading. In contrast, the Ca2+/Mg2+ loaded resin achieves a separation efficiency of 23.3 % at the same flow rate. As the boron loading rate decreases to 10 %, the separation efficiency increases to 42.6 %. The flow rate also plays a crucial role, as an increase corresponds to a decrease in separation efficiency. Notably, the Finex CS10GC ion exchanger in Na+ form consistently exhibits superior separation efficiency and band resolution. A mathematical model is introduced to simulate the effective separation of boric acid from other impurities. The quality of the recovered boric acid conforms to the standard grade (Merck KGaA), exhibiting a purity level within the range of 99.5–100 %, suggesting substantial economic value. The proposed recovery process contributes significantly to environmental preservation by mitigating waste discharge, exemplifying a noteworthy commitment to resource conservation.
Compositional shifts in Microbial diversity under traditional banana cropping systems of Sub-Saharan Africa
(MDPI, 2022-05-16) Kaushal, Manoj; Tumuhairwe, John Baptist; Kaingo, Jacob; Malingumu, Richard; Nakamanya, Florence; Taulya, Godfrey; Coyne, Danny
Improvements in the crop productivity, soil health, and sustainable intensification should be premised on the better understanding of interactions between the cropping systems and soil microbial diversity. In this study, we assessed variations in the microbial communities across the traditional banana-based cropping systems of contrasting monocrop vigor (vigorous or V vs. nonvigorous or NV) and the cropping system (monocrop or MC vs. intercropped or IC) using 16S rDNA (V3–V4) and ITS2 amplicon deep sequencing via Illumina platform. Sequencing results of the bacterial and fungal communities showed high variability among MC and V cropping systems. The abundances of Proteobacteria, Firmicutes, and Actinobacteria were significantly higher in NV (non-vigorous) and V (vigorous) cropping systems; and the abundances of Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes in the MC (monocropping) than IC (intercropping). There were high relative abundances of Pseudomonas (6.1–37.43%), Bacillus (4.5–20.4%), Rhizobium (1.4–6.5%), and Devosia (1.5–6.7%) in the cropping systems. The dominant family of fungal class Incertae_sedis was Mortierellales, which accounted for 8.79–41.12% of total taxa. This result indicated that the cropping systems are vital for supporting the dynamic microbial diversity specifically beneficial for bacterial communities that helps in promoting synergistic plant-soil interactions and total productivity under resource poor conditions of smallholder farmers in sub-Saharan Africa (SSA).
Conforming to agricultural water reuse criteria: wastewater recovery by electrooxidation integrated with nanofiltration/reverse osmosis
(Springer Nature, 2023-02-21) Çiftçioğlu‑Gözüaçık, Bengisu; Omwene, Philip Isaac; Ergenekon, Sinem Merve; Karagunduz, Ahmet; Keskinler, Bülent
In this study, two membrane configurations were investigated for water recovery in order to determine the potential for quality irrigation water production from alkaloid industry wastewater. In the first configuration, electrooxidation (EO) was used as a pretreatment before the NF90/BW30 units. In the second configuration, a single-pass, two-stage system consisting of NF4 and NF90/BW30 membranes was applied by replacing the EO unit with NF4. The initial and final fluxes in the single-pass two-stage system with NF4 and NF90 were calculated as 10.2 Lm− 2h− 1 and 5.4 Lm− 2h− 1, respectively. Initial fluxes for the NF4 + BW30 and EO + BW30 combinations were 9.4 Lm− 2h− 1 and 3.2 Lm− 2h− 1, respectively. Increasing the current density from 256 to 768 A/m2 caused the specific energy consumption (SEC) to increase from 10.26 to 15.84 kWh/kg COD. Scanning Electron Microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used for membrane autopsies. Compliance with the criteria for agricultural reuse of recovered water was evaluated based on four key parameters: salinity, pathogens, nutrients, and heavy metals. The combination of electrooxidation and membrane treatments enabled simultaneous disinfection, reduction of salinity and heavy metals to comparable agricultural water reuse criteria.
Descriptive analysis of heavy metals content of beef from Eastern Uganda and their safety for public consumption
(Frontiers in Nutrition, 2021-02-11) Bogere, Paul; Kasozi, Keneth Iceland; Hamira, Yunusu; Zirintunda, Gerald
In this study, we initiated an effort to generate information about beef safety in Uganda. Our entry point was to assess by atomic absorption spectrophotometry the levels of essential elements copper (Cu), cobalt (Co), iron (Fe) and zinc (Zn), and non-essential elements lead (Pb), chromium (Cr), nickel (Ni), and cadmium (Cd) in 40 beef samples collected from within and around Soroti (Uganda). The information was used to evaluate the safety of consuming such beef against the World Health Organization (WHO) limits. The latter was accomplished by (i) estimating the daily intake (EDI) of each metal in the study area, (ii) modeling the non-cancer health risk using the target hazard quotient (THQ) and (iii) modeling the cancer risk using the incremental lifetime cancer risk (ILCR). The study finds that the mean concentrations (±95% CI) and EDI were in the order of Fe > Zn > Cr > Ni > Pb > Co > Cu > Cd. Cancer risk was found to be due to Ni > Cr > Cd > Pb and significantly higher in children than adults. The latter particularly demonstrates the importance of Ni poisoning in the study area. Overall, while essential elements in our beef samples were below WHO limits (hence no health risks), non-essential elements had high health and cancer risks due to higher levels of Cr and Ni.
Effect of phosphorus-based fertilizer on groundnut yield and incidence of groundnut rosette disease in West Nile Region of Uganda
(African Journals Online, 2023) Abaca, Alex; Odama, Emmanuel; Komakech, Alfred; Kassim, Sadik; Walakira, John K.
The objective of this study was to establish the effects of Di-ammonium phosphate (DAP) fertilizer micro-dosing on yields and the incidence of groundnut rosette disease (GRD) on five groundnut varieties in West Nile region of Uganda. The field experimental design used in this study was 5x2 factorial laid in a randomized complete block design (RCBD) with three replicates per location across 6 locations. The results indicated that there were significant (p = 0.05) differences in groundnuts yields across locations and varieties (0.554 – 1.742 tons per hectare) with or without micro-dosing with DAP fertilizer. The effects of DAP fertilizer micro-dosing in groundnut production were twofold: increase in yields across locations from 427.27kg/acre with no micro-dosing to 525.73kg/acre with micro-dosing (23.04% increment) and varieties from 420.46kg/acre with no micro-dosing to 529.71kg/acre with micro-dosing (13.77% increment); and a reduction of groundnut rosette virus disease incidence across locations from 15.13% with no micro-dosing to 11.20 with micro-dosing (27.76% reduction) and on varieties from 15.08% with no micro-dosing to 11.82% with micro-dosing (34.62% reduction). This is the first report of a prospective DAP fertilizer micro-dosing alongside other improved agronomic practices which can be integrated fully into groundnut production in West Nile region of Uganda. To manage yields and GRD incidences, micro-dosing of crops should be taken as a climate smart technology as identified by Food and Agricultural Organization.
Evaluation of newly released cassava varieties for yield performance, reactions to cassava diseases and farmers’ preference in Adjumani district of Uganda
(Journal of Agricultural Science, 2021-03-15) Abaca, Alex; Odama, Emmanuel; Komakech, Alfred; Asiku, Baron; Andema, A. Andrews; Sadik, Kassim
Cassava viral diseases particularly cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) have put pressure on cassava breeders to develop varieties that are resistant/tolerant to them. Several cassava varieties have been rolled out to farmers with the latest being NAROCASS series that are tolerant to these diseases. The yield performance of these new varieties have not been documented in some sub zones like Adjumani district that falls within a major West Nile agro-ecology of Uganda. Therefore this study sought to established yield performances of, reactions to major diseases, and farmers’ preference to these newly released cassava varieties in Adjumani. Results showed significant (P ≤ 0.05) differences among cassava varieties and experimental sites for all the parameters evaluated. Average yield performance by varieties were in the order of a local cassava—Alifasia (8.7 t/Ha) lowest, NAROCASS 2 (18.55 t/Ha), NASE 14 (33.97 t/Ha), NASE 19 (41.26 t/Ha), and NAROCASS 1 (41.71 t/Ha) highest. CMD foliar symptom was present at all sites on a local cassava—Alifasia, and on NAROCASS 1 in Ayiri parish, Ukusijoni sub-county. CBSD foliar symptoms were observed on off-types (TME 14) in the plot of NASE 14 in Miniki Parish only whereas CBSD root necrosis was observed at all sites on the local cassava—Alifasia, and on NASE 19 in Maaji parish, Ukusijoni sub-county. Cassava root rot disease was localised in Ukusijoni sub-county only. Farmers’ preferences to these newly released cassava varieties were in the order of NASE 19 (40.96%), NAROCASS 1 (24.86%), NAROCASS 2 (15.82.28%), NASE 14 (15.54%), and a Local cassava—Alifasia (2.83%). Result from this study strengthens the information gap in the breeding process towards developing a cassava variety with farmer-preferred attributes, and can also inform the utilisation of these improved cassava varieties in Adjumani district.
First report of banana bunchy top disease caused by Banana bunchy top virus in Uganda
(Wiley, 2021-11-16) Ocimati, Walter; Tazuba, A.F.; Tushemereirwe, Wilberforce Kateera; Tugume, Joab; Omondi, Bonaventure Aman; Acema, Dan; Were, E.; Onyilo, Francis; Ssekamate, A.M.; Namanya, P.; Kubiriba, J.; Erima, R.; Okurut, A.W.; Kutunga, D.; Blomme, G.
In August 2020, banana plants with characteristic symptoms of banana bunchy top disease (BBTD) caused by the Banana bunchy top virus (BBTV) were observed on two different banana (Musa sp.) mats in backyard gardens in Arua City (GPS coordinates: 2o59’36’’N 30o54’40’’E), West Nile region of Uganda. The plants were severely stunted with short, narrow leaves, chlorotic leaf margins and dark green streaks on petioles and midribs. The affected plants had a rosette-like or bunchy and choked appearance (Figures 1–2). A PCR using specific primers that amplify a 240 bp conserved domain of the BBTV DNA-mRep segment (Mansoor et al., 2005) confirmed the presence of BBTV in leaf, pseudostem and corm samples of the two symptomatic plants. The PCR product from one of the samples was purified and reverse sequenced (GenBank Accession No. OK066320). This sequence showed 98–99% nucleotide sequence identity with multiple BBTV isolates from India (e.g., KX219591, GU085264), Democratic Republic of Congo (DR Congo; e.g. KU687085, KU687070, KU687068), Benin (e.g. JQ437548), Burundi (e.g. JN204198), Australia (e.g. KM607586), USA (Hawaii; e.g., KM607599) and other African and South Pacific countries. To our knowledge, this constitutes the first report of BBTD in Uganda.
From principles to practice:
(Center for International Forestry Research (CIFOR); World Agroforestry (ICRAF), 2022-09) Gassner, Anja; Bande, Marlito; Harrison, Rhett D.; Mercado, Agustin; Miccolis, Andrew; Mukuralinda, Athanase; Neidel, J. David; Okia, Clement Akias; Somarriba, Eduardo; Thorne, Peter
When applying the three principles of agroforestry design (farmer-centredness; aptness to place, people and purpose; and synergy), it is important to recognize that each landscape is unique and should therefore have its own unique agroforestry systems. Trees in these systems can have very different functions, ranging from being flotilla species in systems that focus on food production, to being the flagship species in systems that are designed to restore degraded forested landscapes. This chapter describes a small selection of featured systems to illustrate the different functions of trees and the resulting design and management implications. The featured systems should not be read as blueprints for direct application, but as examples of common and robust systems that might be used in specific locations after appropriate modifications.
Gastrointestinal helminths of semi - domesticated helmeted guinea fowl ( Numida meleagris ) under different management systems in Arua district , Uganda.
(African Journal of Poultry Farming, 2016) Sente, Celsus; Kabasa, David John; Dranzoa, Christine; Gwabali, Damba Andrew; Tushabe, Josephine
Multi-stage and purposive sampling designs were undertaken to identify the smallest unit for extraction of samples to determine the prevalence of gastrointestinal helminths of the guinea fowls in the free-range management system (FRMS) and semi-scavenging management system (SSMS) in Arua district. Gastrointestinal tracts (GIT) were extracted from 120 guinea fowls, 60 from each management system. All the 60(100%) guinea fowls from FRMS harboured helminths, whereas only 49(81.7%) from SSMS were infected. The number of helminths Hymenolepis carioca (X2=17, p<0.001), Heterakis gallinarum (X2= 7.60, p<0.01) and Subulura brumpti (X2=4.82, p<0.05) were significantly higher in FRMS than in the SSMS. The prevalence of all species was higher in the FRMS compared to SSMS except for Hartertia gallinarum (3.3%) which was the same in both systems. Ten helminth species, namely; Hymenolepis carioca, Ascaridia galli, Heterakis gallinarum, Dispharynx spiralis, Raillietina tetragona, Subulura brumpti, Prosthogonimus spp., Hartertia gallinarum, trongyloides avium and Raillietina echinobothrida were identified. The mean worm burden of Hymenolepis carioca (FRMS, 140±21.7; SSMS, 63.4±14.7), Ascaridia galli (FRMS, 7.3±3.5; SSMS, 0.03±0.0) and Subulura brumpti (FRMS, 12.7±2.8; SSMS, 4.3±2.1) were significantly higher in FRMS than SSMS. It is important to separate guinea fowls from other poultry as well as improve hygiene measures in both management systems in order to realise a healthy flock.
Genome-wide association analysis identifies resistance loci for bacterial blight in diverse East African rice germplasm
(Academic Journals, 2023-07-31) Okello, Moses; Mildred, Ochwo S.; Lamo, Jimmy; Onaga, Geoffrey; Odong, Thomas L.; Tusiime, Geoffrey; Tukamuhabwa, Phinehas; Mukasa, Settumba B.; Wasswa, Peter; Ogwal, Jonathan; Oliva, Ricardo
Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of rice bacterial blight disease has been extensively characterized, and loci against different races identified. Many rice cultivars have been developed and utilized to combat the disease, however, due to the rapid evolution of Xoo, several resistances have broken down. The continuous challenge of ever-evolving Xoo and the breakdown of resistance in cultivated rice varieties make it even more important to discover new loci to enable sustainable durable deployment of broad-spectrum resistance genes in elite breeding lines. African germplasm can be exploited as reservoirs of useful genetic variation for bacterial blight (BB) resistance. This study was conducted to identify loci associated with BB resistance and new genetic donors for the breeding program. To identify candidate sources of resistance for advancing breeding, four virulent strains of Xoo (PXO99, MAI1, BAI3, and Xoo3-1) were used to screen 78 East African accessions by genome-wide association studies. The diverse accessions' core genetic base exhibited high resistance to the Xoo strains. 50.63% of the accessions were highly resistant to the Philippines strain PX099, while 20.25% were highly susceptible to the virulent West African strain MAI1. Two novel resistant loci significantly associated hotspots were identified using 1901 SNPs. The two hits were located on chromosome 12 (Xa25) and Chr. 6 (Xa7, Xa27, Xa33). Novel loci were identified that gives a useful basis for more investigation and a wide core genetic pool of high resistance for broad-spectrum resistance for genetic improvement.
Genome-wide association mapping in rice MAGIC indica panel detects QTLs and genes for broad-spectrum resistance breeding against African bacterial blight
(ORYZA-An International Journal of Rice, 2024-03-30) Okello, Moses; Ssemakula, Mildred Ochwo; Lamo, Jimmy; Onaga, Geoffrey; Odong, Thomas L; Geoffrey, Tusiime; Tukamuhabwa, Phinehas; Mukasa, Settumba B; Wasswa, Peter; Ogwal, Jonathan; Oliva, Ricardo
Rice (Oryza sativa) bacterial blight (BB) is a direct threat to production in Africa. The extent of damage on the continent is not known. We conducted a genome-wide association study (GWAS) to seek out Quantitative trait loci (QTL) that confer the broad-spectrum resistance (BSR) to rice Xanthomonas oryzae pv. oryzae in the rice Multiparent advanced generation intercross (MAGIC) population. The diverse genetic composition and high levels of recombination, are potential resources for the identification of QTL for BSR. Dealing with the everevolving Xoo requires identification of novel R gene and resistance quantitative trait loci (QTL). We conducted a genome-wide association study (GWAS) using 250 rice MAGIC indica panel to evaluate for resistance to three Xoo strains from Cote D'Ivoire, namely XooCIkor, XooCIgag and XooCIcii2 which are prevalent highly virulent pathotypes. Using the 3 K RG 4.8mio filtered SNP Dataset, a total of 3 QTL associated with BB resistance on chromosome 9, 6 and 5 were identified. The results of the GWAS identified novel loci that gives useful insight for more investigation and also validated known genes underlying resistance to virulent African strains of BB. Genetic donors identified in this will help plant breeders in improving and broadening resistance to BB.
Grain hermetic storage adoption in Northern Uganda: awareness, use, and the constraints to technology adoption
(Scientific Research Publishing, 2022-09-15) Okori, Francis; Cherotich, Sam; Abaca, Alex; Baidhe, Emmanuel; Adibaku, Francis; Onyinge, James Denis
Post-harvest storage losses (PHLs) remain significant in Sub-Saharan Africa (SSA) due to several factors mainly insect pests and molds. Hermetic storage technologies (HSTs) are being promoted to address these storage losses. In Uganda, HSTs were first introduced in 2012. However, its use among farming households remains low today. Data were collected from 306 smallholder farmers from four districts of Northern Uganda using a pre-tested semi-structured questionnaire to understand their knowledge, use, and constraints to the adoption of hermetic storage. A multivariate Logit regression model was used to find the significance of the factors affecting adoption. Results showed low awareness and use of hermetic storage among smallholder farmers. Only 53.3% of the interviewed farmers were aware of the use of hermetic storage for grain storage. The SuperGrain bag was the most known form of hermetic storage (35.3%), followed by the Purdue Improved Crop Storage (PICS) bag (34.9%), metallic silo (15.5%), and plastic silo (14.4%). Hermetic storage use was even lower as only 17.6% of the surveyed farmers were using one or more forms of hermetic storage to store their grains. Insect pest management without chemical insecticides was the main reason (83.1%) for hermetic storage use. About 75.5% of those aware of hermetic storage had received training in the technology. Hermetic storage use in farming households led to improved food availability, household income, and nutrition. Lack of local availability (50.2%), high costs (37.8%), and inadequate knowledge (6.9%) were the main constraints hindering the adoption of hermetic storage in Northern Uganda. The logit regression models showed that only training in hermetic storage significantly (p = 0.002) affected farmers’ decision to adopt hermetic storage. Understanding the factors that constrain the adoption of HSTs could provide policymakers with important information to initiate and design policies and programs aimed at reducing crop storage losses.
Histological features of the gastrointestinal tract of elongate tigerfish, Hydrocynus forskahlii (Cuvier, 1819), from Lake Albert
(Springer Nature, 2024-05-10) Kasozi, Nasser; Iwe, Gerald D.; Langi, Sandra; Namulawa, Victoria T.; Walakira, John
The tigerfsh (Hydrocynus forskahlii) is an important food fsh in diferent regions of Africa. As such, interest in its performance and nutritional requirements as a potential candidate for aquaculture is increasing. Characterization of the morpho-histological features and functions of the gut provides valuable insights into the feeding physiology and digestive system of fsh species. An investigation of the morpho-histological features of the gastrointestinal tract of H. forskahlii captured from Lake Albert was conducted over an eight-month period. The digestive tract of H. forskahlii is characterised by a short oesophagus, well-developed and distensible stomach and moderately long intestine. The oesophagus had a higher abundance of mucous-secreting goblet cells compared to other digestive tract tissues. The stomach had a bag-like shape for swallowing large prey and was distinguishable into the cardiac, fundic and pyloric regions. Both the cardiac and fundic regions of the stomach had numerous gastric glands, whereas the pyloric region had large compound folds consisting of pseudo-stratifed columnar epithelium. Many goblet cells were also observed in the mid and posterior regions of the intestine. The relative length of the gut of the H. forskahlii was 1.27±0.03 cm, and it had a total of 20–22 pyloric caeca. The liver was observed to be divided in lobules by a central vein contained within connective sheets. Irregular cords of hepatocytes were also visible throughout the parenchyma.The histological features of the H.forskahlii gut observed in the present study are consistent with those of carnivorous and omnivorous fsh.
Indigenous Knowledge Influences Cowpea ( Vigna Unguiculata ) Production among Smallholder Farmers in Northern Uganda
(Scholars World-International Refereed Journal of Arts, Science & Commerce,, 2018) Ayaa, Franciska; Alumai, Alfred; Dranzoa, Christine
This study documented the available indigenous knowledge (IK) on cowpea production in northern Uganda. The study focused on smallholder farmers along the River Nile belt in Nebbi, Arua, and Moyo districts in Uganda where cowpea is still grown widely. Data was collected from 300 randomly selected smallholder farmers in the study area, using a semi-structured survey questionnaire. Our findings show that only 17% of farmers cultivated cowpea on more than 1 acre. The majority cultivated cowpea on 1 acre (31%) and half an acre (30%). We found that 5 cowpea varieties (small brown helium, medium black, pungent smell, small white red helium, and large white red helium) are grown. The varieties that are commonly grown are small white red helium (34.7%) and large white red helium (48.3%). However, the findings reveal that the small brown, medium black and pungent smell varieties are becoming extinct. The major source of seeds for farmers was found to be local markets (36.3%), farmers’ own preserved seeds from previous seasons (28.3%), purchasing and using own preserved seeds (23.0%), urban markets (2%), purchased from both local and urban markets (6%), and borrowed from other farmers (1%). The major field pests that affect cowpea production were found to be aphids, glow worms, and beetles. Farmers control them using IK methods, including homemade remedies (69.3%) and handpicking (36.1%). Farmers control storage pests using storage, farmer use neem leaves or wood ash spread in granaries (25.8%), “osikusi” (3.9%), “dula” (1.9%), underground tunnels (4.7%), pots (0.3%), and empty drums (0.3%). These results suggest that IK plays a significant role in cowpea production, and is critical to enhancing socio-economic growth, increasing income, and ensuring food security among smallholder farmers.

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