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ItemShocks, coping strategies, and livelihood security in the drylands of Uganda and Kenya(Makerere University, 2025)Recurrent shocks and crises threaten dryland household livelihood security by jeopardizing their income and other means of sustenance. In the absence of social protection and weak institutional support, households resort to problematic coping strategies that have the potential to trap them in a vicious cycle of livelihood insecurity. This study employed a panel data set from 698 households in the drylands of Uganda and Kenya to assess seasonal and country-level variations for 21 shock events experienced by households, coping strategies adopted and their determinants, and the determinants of livelihood security. Shocks and coping strategies were analyzed using student t-tests, while the determinants of coping strategy choices and livelihood security were analyzed using the multivariate probit and Tobit models respectively. Descriptive statistics show that shock incidences are significantly higher in Uganda’s drylands, particularly in the wet season. Results further show that in the event of livestock deaths, livestock illness, and reduced crop harvest, the important factors that determine coping strategies employed by households are gender of the household head, membership to groups, the farmland size that is available to households for crop and livestock farming, the number of income sources, access to extension services and credit, and the proportion of shocks experienced by households. The livelihood security index shows that all households in the drylands of Uganda and Kenya are at precarious livelihood security levels, with economic security being the lowest for both countries. Results further show that households whose heads have higher levels of education, which have more livestock (TLUs), which belong to a group and have access to credit, and those living in the agropastoral region are more likely to have higher livelihood security levels. On the other hand, households with older heads, a higher dependency ratio, access to extension, those that experienced a higher proportion of shocks, and those in the drylands of Uganda are more likely to have lower livelihood security levels. The study recommends strengthening social protection programs, promoting improved livestock management, building resilient agropastoral systems, promoting financial inclusion, strengthening social networks, and complementary investment in human capital and land productivity to build resilient livelihoods.
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ItemSpatial and Temporal Soil Water Availability in a Cultivated Inland Valley Wetland in Central Uganda( 2023)Cultivation of inland valley wetlands contributes significantly to the livelihoods of rural communities in Uganda and East Africa at large. This adversely affects the stability of these ecosystems through alteration of the water retention. A study was conducted along a cultivated inland valley in Namulonge Lake Kyoga basin in Central Uganda. The main objective was to understand the spatial-temporal dynamics of soil water availability under the different wetland uses along three landscape positions. Specifically, the study was conducted to: (i) Determine the spatial variation of soil moisture across the major agricultural land uses and slope positions in the inland valley wetland; (ii) Investigate the temporal trend of soil moisture across major agricultural land uses and slope positions in the inland valley wetland; (iii) Quantify the amount of runoff generated from the major agricultural land uses across different landscape positions in the inland valley wetland. A Completely Randomized Block Design was established where the treatments included three land uses, that is upland annual crop (i.e., maize, beans, sweet potatoes land uses); Arrowroots and Fallow, established along three landscape positions as blocks (Fringe/Upper, Middle, Riparian/Lower) of the inland wetland valley. Daily soil moisture was measured using Frequency Domain Reflectometry sensors under the three land uses and along the hydrological positions at four soil depths 10, 20, 30 and 40 cm from March to September 2020. The model was calibrated using the daily soil moisture and groundwater level for each land use along the hydrological positions. Results indicated that soil moisture content under different land uses varied significantly along the landscape positions with soil depths (p<0.05). Along the riparian position, the land use (arrowroots-yam) at depths to 0-20 cm and the land use (upland crops) at depths 20-40 cm had highest value of moisture content. Along the middle position, the land under fallow at depths 0-20 cm and the land use arrowroots at depths 20-40 cm had highest value of moisture content. Along the fringe position, the land use upland crops at depths 0-40 cm had highest value of moisture content. Soil moisture content trend for both the rain and dry seasons were well reproduced by the model for the two top soil layers (0.5=R2≤0.90). Monthly (temporal) soil moisture content increased quadratically in the different land uses with seasonal trends higher under arrowroots than upland crops and fallow lands. Runoff varied significantly with land uses and landscape positions. The study demonstrated that there is significant influence of land use on soil moisture availability, run off and this effect varies with landscape position. The land use under arrowroots had the highest capacity to retain soil moisture for long compared to other land uses, hence the land use could be instrumental in building resilience to water stress compared to other land uses in the in-land valley.
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ItemThe resistance of tropical maize germplasm to ear rot caused by Fusarium verticillioides in Uganda(Makerere University, 2025)Maize (Zea mays L.) is the third most important cereal in the world but unfortunately its yield is below what is expected and this could be attributed to various abiotic and biotic factors, one of them being Fusarium ear rot. Global maize production is impacted by the destructive fungal disease known as Fusarium ear rot, which is caused by Fusarium verticillioides. In addition to causing significant yield losses, it also produces toxic mycotoxins such as Fumonisins which are harmful to both humans and livestock if consumed. The occurrence of ear rots can vary greatly from year to year as well as field to field. This disease causes great concern in maize production worldwide, as it is considered to have a severe impact on the maize grain yield and income in the market. The best approach to manage Fusarium ear rot (FER) is to breed for resistance since there are no documented FER resistant varieties in Uganda. This study set out to: i) identify possible sources of Fusarium ear rot resistance, ii) evaluate the type of gene action governing FER resistance, and iii) pinpoint genomic regions and putative genes associated with FER resistance in maize. In the first part of the study, a genetically diverse collection of 150 maize inbred lines was screened as probable sources of resistance to FER using artificial inoculation with the toothpick method in the field for two seasons. At harvest, ears were scored for FER severity and scored. Significant differences were noted between the two seasons, with inbred lines exhibiting varied levels of performance. Ten inbred lines consistently exhibited low disease severity across both seasons, suggesting they could serve as valuable sources of resistance for breeding programs. The second study investigated the gene action behind resistance to infection by F. verticillioides in 13 inbred lines. The North Carolina II mating design was used to generate 42 hybrids which were then evaluated in five environments. The Genotype X environment interaction was highly significant (P < 0.001), as well the GCA effects and the GCA X environment interactions. Inbred lines JPS31-89, JPS31-167, JPS30-5, JPS30-9 and JPS30-11 emerged as the best combiners for FER making them good candidates to use in breeding resistant varieties. Additive gene effects played a more significant role than non-additive gene effects in conferring resistance to FER. The hybrids JPS30-11/JPS30-13, JPS30-12/JPS30-21, and JPS30-11/JPS31-4 were identified as the most effective combinations for FER resistance. Using DarTseq markers, the final study sought to identify genomic regions and potential genes associated with FER resistance. A total of 20,900 single nucleotide polymorphisms (SNPs) were used to genotype 150 inbred lines. Two significant SNP markers on chromosomes 1, and 4 were found by the Genome-Wide Association Study (GWAS) and these accounted for 9.8 and 11.9% of the phenotypic variation. The significant SNP marker 2396181|F|0-39:G>T-39:G>T identified on chromosome 1 was annotated to the candidate gene GRMZM2G104516, which encodes zinc finger proteins. These proteins play critical roles in various biological processes, including transcription, DNA recognition, translation, RNA packaging, photosynthesis, and regulating resistance mechanisms to both biotic (pathogen response) and abiotic stresses. On chromosome 4, SNP marker 2463074|F|0-20:G>A-20:G>A was annotated to candidate gene was GRMZM2G047319 which belongs to the serine/threonine protein class which play a role in signalling during pathogen recognition and the subsequent activation of plant defence responses. These results showed that resistance to FER is a complex trait regulated by several genes with small effects, and it involves multiple pathways. More in-depth biochemical and molecular studies are recommended to understand this trait as well as validate these markers to be used for breeding for resistance to Fusarium ear rot.
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Itemasfas( 2024)
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ItemCompliance with Maize grain standards in a regional market among farmers in Mubende District(Makerere University, 2025)This study examines compliance with grain post-harvest standards and their economic implications among smallholder maize farmers in Uganda. Smallholder maize farmers in Uganda are trapped in a low-quality equilibrium (where farmers lack quality incentives and buyers avoid local markets due to inconsistent produce quality). Using a cross-sectional survey of 381 maize farmers, the study characterized, analyzed the determinants of compliance, and assessed the associated gross profit. Data analysis involved descriptive statistics, the Probit regression model, and two-stage least squares. Findings revealed that education levels, land size, farming experience, literacy, labor type, and access to premium price varied between compliant and non-compliant maize farmers. The findings revealed that compliance with grain standards is driven by the literacy rate, land size under maize production, farmer experience in maize production, the type of labor used by the farmer, and market information. Further findings reveal that compliance with the grain standards negatively affects maize farmers' gross profit; however, the result is not statistically significant. Other factors that significantly affected maize farmers' gross profit included education, household size, access to credit, and maize acreage. The study recommends that the government, through the Ministry of Trade, Industries, and Cooperatives, strengthen market systems by supporting farmer cooperatives and warehouse receipt systems to aggregate compliant maize for premium buyers (processors, exporters). Subsidizing quality-enhancing technologies and providing value chain-focused agricultural loans would improve compliance incentives, market access, and smallholder profitability.