Agricultural and Veterinary Sciences

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Genotype by Environment Effects on Promiscuous Nodulation in Soybean (Glycine max L. Merrill)
(Agric Food Secur, 2017-03-17) Agoyi, Eric E.; Odong, Thomas L.; Tumuhairwe, John B.; Chigeza, Godfree; Tukamuhabwa, Phinehas
Understanding factors influencing the expression of a trait is key in designing a breeding program. Genotype by environment interaction has great influence on most quantitative traits. Promiscuous nodulation is a trait of importance for soybean production in Africa, because of the soil bacteria Bradyrhizobium japonicum not being indigenous in most African soils. Most soybean cultivars require B. japonicum for nodulation leading to the need for seed inoculation before sowing soybean in Africa. Few cultivars have capability to nodulate with Bradyrhizobia spp. that are different from B. japonicum and native in African soils. Such cultivars are termed “promiscuous cultivars.” Field experiments were conducted in six locations in Uganda for two seasons, to investigate the extent of environmental influences on the nodulation ability of promiscuous soybean genotypes. Additive main effect and multiplicative interaction effects showed highly significant environment and genotype by environment (G × E) interaction effects on all nodulation traits. G × E interaction contributed more to the total variation than genotypes. The genotypes Kabanyolo I and WonderSoya were the most stable for nodules’ dry weight (NDW), which is the nodulation trait the most correlated with grain yield. Genotype UG5 was the most stable for nodules’ number (NN), and Nam II for nodules’ effectiveness (NE). The genotype NamSoy 4M had the highest performance for NN, NFW, and NDW, but was less stable. WonderSoya had the highest NE. Genotype and genotype by environment analysis grouped environments into mega-environments (MEs), and four MEs were observed for NDW, with NamSoy 4M the winning genotype in the largest ME, and Kasese B the ideal environment for that nodulation trait. This study provides information that can guide breeding strategies. The low genetic effect that led to high environmental and G × E interaction effects raised the need for multi-environments testing before cultivar selection and recommendation. The study revealed genotypes that are stable and others that are high performing for nodulation traits, and which can be used as parental lines in breeding programs.
Morphological and molecular identification of ixodid tick species (Acari: Ixodidae) infesting cattle in Uganda
(Parasitology Research, 2020) Balinandi, Stephen; Chitimia-Dobler, Lidia; Grandi, Giulio; Nakayiki, Teddy; Kabasa, William; Bbira, Johnson; Lutwama, Julius J.; Bakkes, Deon K.; Malmberg, Maja; Mugisha, Lawrence
In Uganda, the role of ticks in zoonotic disease transmission is not well described, partly, due to limited available information on tick diversity. This study aimed to identify the tick species that infest cattle. Between September and November 2017, ticks (n = 4362) were collected from 5 districts across Uganda (Kasese, Hoima, Gulu, Soroti, and Moroto) and identified morphologically at Uganda Virus Research Institute. Morphological and genetic validation was performed in Germany on representative identified specimens and on all unidentified ticks. Ticks were belonging to 15 species: 8 Rhipicephalus species (Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus microplus, Rhipicephalus decoloratus, Rhipicephalus afranicus, Rhipicephalus pulchellus, Rhipicephalus simus, and Rhipicephalus sanguineus tropical lineage); 5 Amblyomma species (Amblyomma lepidum, Amblyomma variegatum, Amblyomma cohaerens, Amblyomma gemma, and Amblyomma paulopunctatum); and 2 Hyalomma species (Hyalomma rufipes and Hyalomma truncatum). The most common species were R. appendiculatus (51.8%), A. lepidum (21.0%), A. variegatum (14.3%), R. evertsi evertsi (8.2%), and R. decoloratus (2.4%). R. afranicus is a new species recently described in South Africa and we report its presence in Uganda for the first time. The sequences of R. afranicus were 2.4% divergent from those obtained in Southern Africa. We confirm the presence of the invasive R. microplus in two districts (Soroti and Gulu). Species diversity was highest in Moroto district (p = 0.004) and geographical predominance by specific ticks was observed (p = 0.001). The study expands the knowledge on tick fauna in Uganda and demonstrates that multiple tick species with potential to transmit several tick-borne diseases including zoonotic pathogens are infesting cattle.
Livelihood dynamics and challenges to wellbeing in the drylands of rural East Africa – the Drylands Transform study population in the Karamoja border region
(Taylor & Francis Ltd, 2025-04-24) Schumann, Barbara;; Turinawe, Alice;; Lindvall, Kristina ;; Kyanjo, Joseph Lule;; Kuule, Derick Ansyijar;; Kawira, Caroline;; Mwangi, Annrose;; Mwangi, Peter;; Hörnell, Agneta
BackgroundThe Karamoja region in the East African drylands is a rural, impoverished setting where pastoralism is increasingly replaced by other livelihood strategies. Understanding the socioeconomic contexts as well as their local variations is key for sustainable development of communities.ObjectiveThe aim of the present paper is to describe the baseline survey of the Drylands Transform project, its setting, methods and key findings.MethodsIn June 2022, a survey was conducted with 944 randomly selected households at four study sites in the Karamoja border region of Kenya and Uganda. Data were analyzed using descriptive statistics.ResultsMain livelihood forms were pastoralism and agropastoralism, while many households also relied on other sources of income. At some study sites, livestock keeping was abandoned by many residents due to cattle raiding and droughts. Only 4% of households were rated as food secure. The proportion of malnutrition among children aged 6-59 months varied across sites between 3% and 17% and was considerably higher among women.ConclusionsClimate change, water shortage, social conflicts and marginalization pose barriers to food security and wellbeing for rural populations in the East African drylands. There are, however, opportunities for development through income diversification, the improvement of land health, the promotion of kitchen gardens and other measures of sustainable agriculture.
Addition of beans four and Mukene (Rastrineobola argentea) powder improves the nutritional, sensory and functional properties of maize four for porridge
(Springer International Publishing, 2025-02-11) Tumuhimbise, Gaston Ampek;; Tumwine, Gerald;; Nabubuya, Agnes ;; Mutatina, Boniface;; Rwebiita, Atucungwiire;; Basaza, Robert
Malnutrition is a burden among young children in Uganda due to inadequate intake of the required nutrients. Inadequate nutrient intake is partly caused by the use of plant based foods to wean infants. The plant based foods are high in calories but limited in other essential nutrients such as proteins, vitamins and minerals. This study aimed to develop maize-based composite flour enriched with locally available legumes namely; beans and soybeans and Rastrineobola argentea powder. Two formulations of maize-based composite flours with beans, soybeans and Rastrineobola argentea were made with one containing roasted beans and the other with unroasted beans. Flour blends were produced by mixing 55:20:20:5 (Maize: beans: soybeans: Mukene ( Rastrineobola argentea ) powder, w/w) while 100% maize flour was used as the control. The proximate composition results were: moisture content (5.03 to 5.32%), crude protein (10.11 to 19.00%), carbohydrate (63.17 to 79.60%), crude fat (3.96 to 4.52%) and crude fiber (2.10 to 4.40%). Energy content was between 332 and 377 kcal/100 g. Mineral content were: Calcium (14.80 to 1869.12 mg/100 g), Iron (1.45 to 58.97 mg/100 g). Functional properties results obtained were: water absorption capacity (150.71 to 305.00%), oil absorption capacity (86.01 to 200.00%), bulk density (0.63 to 0.83 g/ml), swelling power (2.6 to 7.8%), and solubility (0.5 to 19.0%). The substitution of maize flour with beans, soybean and Rastrineobola argentea had significant reduction in the overall sensory acceptability of porridge. Addition of beans, soy and Rastrineobola argentea powder flour resulted into maize based composite flour with high peak (490.33 to 839.33 cP), trough viscosity (467.00 to 803.33cP), set back (1124.00 to 1721.33cP) and final viscosities (1591.00 to 2524.67cP). Peak time (5.93 min) and pasting temperature (86.40 to 89.867 °C) of the composite flour were lower than those of maize flour (peak time; 6.93 min, pasting temperature; 93.67 °C). It was concluded that the addition of beans, soybeans flour and Rastrineobola argentea powder to maize flour enhanced the nutritional and functional properties of the composite flours. Therefore, the developed composite flour can be used in the management of undernutrition in developing countries.
Survey on human-designated antiretroviral (ARV) drug residues in broiler chicken, domestic pigs, and animal feeds in, Tanzania
(Springer Berlin Heidelberg, 2025-03-28) Kimera, Zuhura I.;; Shimo, Peter;; Balandya, Emmanuel C. ;; Matee, Mecky I. N.;; Adams, Lisa V.
BackgroundRecent reports have indicated the use of antiretroviral (ARV) drugs in animal production in neighboring Uganda, with further reports of use in several African countries. This cross-sectional survey was conducted in nine districts in Tanzania and involved screening for the presence of three first-line ARVs (lamivudine, nevirapine, and efavirenz) residues in the muscle and blood of domestic pigs and broiler chickenss and in sampled animal feed and water. Residues were determined using liquid chromatography and mass spectrometry (LC–MS/MS). The method involved calibration of the lower limit of quantitation (LLOQ) and limit of detection (LOD). ARVs were detected and quantified using the multiple reaction monitoring (MRM) system.Results131 (66.8%) of the 196 samples of muscle, blood, and animal feed were found to contain lamivudine residues, with the highest concentration detected in domestic pig blood and muscle (7.58 mg/kg) and the lowest concentration (0.01 mg/kg) in broiler chicken feed. There was a significant relationship between the presence of lamivudine by sample type and sample origin (p = 0.000). Nevirapine and efavirenz drugs were not detected in any of the collected samples. No ARV residues were detected in water samples (n = 37).ConclusionsThis survey confirms the use of ARVs in animal production in Tanzania as evidenced by the presence of residues in animal feeds. We found lamivudine residues in domestic pigs and broiler chickens at concentrations higher than those recently reported in other East African studies. Farmers living with HIV may be using ARVs from their prescribed medication, which may lead to poor adherence and the emergence of drug resistance. Besides direct human and animal health issues, these residues in animal feeds and animal excreta can lead to environmental contamination leading to several negative impacts. We recommend a total ban on human-designated ARVs in animal production and advocate for comprehensive studies and monitoring systems across African countries to reveal potential societal and other reasons for their use and provide comprehensive solutions using One Health approaches. Publicly Available Content Database
An evaluation of the environmental impact assessment practice in Uganda: challenges and opportunities for achieving sustainable development
(Heliyon, 2020-05-08) Taako, Edema George; Kiemo, Karatu; Andama, Edward
Environmental Impact Assessment (EIA) is a broad process that emerged from the National Environment Policy Act, 1970 in the U.S. Its primary objective is to generate information on the likely impacts of a project on all aspects of the environment and used in agency decision making and in the long run protect the environment and achieve sustainable development. EIA practice in Uganda was formally established through the National Environment Act, 1995 and now in practice for over 25 years. However, there is increasing level of water pollution especially Lake Victoria, rivers, streams, aquifers and soils. This research reviewed the institutional, legal and regulatory framework for EIA, related literature and EIA documents especially EIA reports and conducted key EIA stakeholders survey using questionnaires to identify capacity and practice issues. The results revealed that, there was gap between law and practice arising from inadequate and ineffective public participation, weak follow-up, low key stakeholder's capacity, political interference, lack of SEA practice and not embracing EIA in a transboundary context. However, there is fairly good and comprehensive institutional, legislative and regulatory framework for EIA, good local governance structures, adequate staffing, robust national planning framework, active non-state actors and regional groupings. In order to maximize the potential of EIA as a means for achieving the SDGs, we recommended measures to address the challenges facing the EIA practice as well as utilize the existing opportunities within the context in which EIA is applied.
Incidence of Viruses and Viruslike Diseases of Sweetpotato in Uganda
(Plant disease, 2003-02-23) Mukasa, Settumba B.; Rubaihayo,Patrick R.; Valkonen, Jari P. T.
Sweetpotato plants were surveyed for viruslike diseases and viruses in the four major agroecological zones of Uganda. Testing of 1,260 sweetpotato plants, of which 634 had virus-like symptoms, showed that virus disease incidence ranged from 2.7% (Soroti district, short grassland—savannah zone) to 20% (Mukono district, tall grass—forest mosaic zone). Sweet potato chlorotic stunt virus (SPCSV), Sweet potato feathery mottle virus (SPFMV), Sweet potato mild mottle virus (SPMMV), and sweet potato chlorotic fleck virus (SPCFV) were serologically detected and positive results confirmed by immunocapture reverse transcriptase polymerase chain reaction (IC-RT-PCR) and subsequent sequence analyses of the amplified fragments, except SPCFV, which lacked sequence information. SPCSV and SPFMV were detected in all the 14 districts surveyed, whereas SPMMV and SPCFV were detected in 13 and 8 districts, respectively. Logistic regression analysis revealed that SPCSV and SPFMV, SPFMV and SPMMV, and SPFMV and SPCFV more frequently occurred together than any other virus combinations or as single virus infections. Co-infections of SPCSV with SPFMV and/or SPMMV were associated with more severe and persistent symptoms than infections with each of the viruses alone. Several plants (11%) displaying viruslike symptoms did not react with the virus antisera used, suggesting that more viruses or viruslike agents are infecting sweetpotatoes in Uganda.
Insecticide application to reduce pest infestation and damage on cowpea in Uganda
(African Plant Protection, 1998-08-05) Omongo, C.A.; Adipala, E.; Ogenga-Latigo, M.W.; Kyamanywa, S.
Field assessments were carried out in seven districts of eastern and northern Uganda to establish pest infestation of cowpea (Vigna unguiculata) and the extent of insecticide usage to control these pests. More than 60 % of the farmers in eastern Uganda applied insecticides to control cowpea pests whereas no farmers in the northern region used chemieels for this purpose. The extent of pest infestation at different crop growth stages appeared to influence pesticide application, with mostlarmers spraying during the vegetative (30 %) and flowering (50 %) stages. and only a few at podding (10 %). There was evidence 01 ineffective/uneconomical use of insecticides. On-farm trials indicated that insecticide protection at all crop growth stages gave the best control. leading to yield gains 01 more than 50 %. Spraying during vegetative and flowering stages was also effective. giving yield gains of about 40 %. A three-spray programme (at vegetative growth. flowering and podding) was most profitable in the short rainy season at Serere (marginal return = 6.08) and second best in the long rainy season at Kabanyolo (marginal return = 4.35).
Interactive effects of host, pathogen and mineral nutrition on grey leaf spot epidemics in Uganda
(European Journal of Plant Pathology, 2004-02-08) Okori, Patrick; Rubaihayo, Patrick R.; Ekwamu, Adipala; Christina, Dixelius
Grey leaf spot incited by Cercospora zeae-maydis is a new devastating foliar disease of maize in East Africa. For effective control, elucidation of the most critical elements of the grey leaf spot disease pyramid is important. This study investigated the role of mineral nutrition, pathogen variability and host resistance in the epidemic. Trials were conducted under field and controlled environments. The 28 isolates used in the controlled environment varied significantly (P ≤ 0.05) in parasitic fitness measured indirectly as disease efficiency, but no infection pattern could be attributed to known C. zeae-maydis pathotypes. Data from field trials showed that host resistance and mineral nutrition significantly (P ≤ 0.05) affected disease efficiency, with highest disease development occurring in nitrogen-augmented plots. Exclusive phosphorus application had no clear effect on grey leaf spot epidemics but combined application with nitrogen significantly (P ≤ 0.05) reduced the predisposition effects of nitrogen to the disease. Overall, treated plots had less disease than unfertilised plots. Fertiliser application had no effect on sporulation capacity, while cultivars significantly affected it. Geographic differences in amount of disease were observed, suggesting environment influences on grey leaf spot incidence. The results suggest that the current grey leaf spot epidemics in East Africa are due to favourable cultivars, poor mineral nutrition and environmental interactions.
Genome-wide association mapping in rice MAGIC indica panel detects QTLs and genes for broad-spectrum resistance breeding against African bacterial blight
(Oryza, 2024-03-30) Okello, Moses; Ssemakula, Mildred Ochwo; Tusiime, Geoffrey; Settumba, B Mukasa; Ricardo, Oliva
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.
Effects of Concentrating Resistance to Northern Leaf Blight of Maize on Agronomic Traits
(East African Agricultural and Forestry Journal, 1995-12-09) Ojulong, H.F.; Adipala, E.; Rubaihayo, P.R.
Lack of appropriate maize varieties in Uganda has • been cited as one of the major factors limiting the production of this crop in the country. Thirty-five per cent of the maize grown in the country comprises improved open-pollinated varieties; 60% comprises unimproved open-pollinated varieties which have resulted from planting many generations of the formally improved open-pollinated varieties (Baguma, 1992). This, coupled with the introduction of susceptible cultivars from Centro International de Majeramiento de Maizy Trigo, Mexico (CIMMYT) led to an outbreak of northern leaf blight (NLB) -in 1988
Genetic Diversity of Phytophthora infestans (Mont.) de Bary in the Eastern and Western Highlands of Uganda
(Journal of Phytopathology, 2002-10-16) Ochwo, M. K. N.; Adipala, E.; Rubaihayo, P. R.; Olanya, M.
Eight isolates of Phytophthora infestans were recovered from late blight infected samples collected from the districts of Mbale and Mbarara in the Eastern and Western highlands of Uganda in 2001 and analysed using mitochondrial deoxyribonucleic acid (DNA) haplotype and Amplified Fragment Length Polymorphism (AFLP) markers. Polymerase chain reaction amplification with the P2 primer followed by digestion with MspI yielded a three-fragment pattern characteristic of isolates belonging to the US-1 clonal lineage; the polymorphism was confirmed by DNA sequencing. AFLP analysis yielded 60 markers, analysis of which clustered the Ugandan isolates with reference to US-1 isolates (US930258 and US940501). These results suggest that the examined Ugandan isolates belong to the US-1 clonage lineage
Knowledge and Perceptions on Banana Xanthomonas Wilt Control 10 Years after the Epidemics in the South Western Agro-Ecological Zone, Uganda
(Open Access Library Journal, 2024-06-07) Kankwatsa, Peace; Kyomugisha, Maggiore; Ntakyo, Proscovia Renzaho; Muhumuza, John Bosco
The East African highland cooking banana (Musa spp.) is a major food security and non-traditional income generation crop in rural and urban areas of the South Western Agro-Ecological Zone (SWAEZ) of Uganda. Being a perennial crop, the vulnerability of banana to the evolving abiotic and biotic stresses is increasing in this major production region. During the late 2000s, the SWAEZ experienced wide-spread and severe banana Xanthomonas wilt (BXW) disease epidemics, which caused 70% - 100% crop and/or yield losses. Through various partnerships, the government of Uganda applied the integrated approaches to provide the needed technical, policy, legal and financial support to rapidly eradicate the disease, strengthen the farmers’ capacities to prevent further plant infections and spread of the “Xanthomonas vasicola pv., musacearum (XVM)” pathogen. Research has shown that the comprehensive and collective action, which focused on rapidly eliminating BXW, reduced the disease prevalence to <5%, but ten years after the eradication campaign, BXW is persistent in SWAEZ. A study carried out in five districts to assess farmers’ knowledge and perception about the BXW control 10 years after the epidemics, found that the disease incidences continue to gradually rise, as efforts to control it continue to decline, which makes the zone prone to another serious epidemic if strong measures are not enforced. Given the knowledge and skills previously imparted to farmers, banana productivity and production for food and income generation have been gradually increasing; livelihoods that are highly dependent on banana have improved and crop production has been diversified in some areas. However, because of the decline in the government’s effort to continue sensitizing, monitoring and enforcing by-laws, the disease inoculum continues to build up and spread. While the majority of the household respondents agreed that the recommended disease control technology packages were very effective, they were also expensive (in terms of labour and non-labour inputs), and too difficult to be applied by the weak and vulnerable community members (females, children, elderly people, sick and other disabled community members). The farmers attributed the disease persistence in the zone to poor monitoring, ineffective use of the recommended disease management technology packages, increased disease pathogen inoculum in abandoned plantations, use of infected planting materials and unsterilized field tools. Therefore, in order to completely mitigate BXW from the SWAEZ, this study recommends that the government reinstate regular awareness creation campaigns, training, and functional BXW eradication task-forces in the banana-producing communities to ensure timely and effective disease control.
Stakeholders’ Perceptions of Agronomic Iodine Biofortification: A SWOT-AHP Analysis in Northern Uganda
(Nutrients, 2018-03-24) Olum, Solomon; Okello, Collins; Odongo, Walter; Ongeng, Duncan; Steur, Hans De
Agronomic biofortification (i.e., the application of fertilizer to elevate micronutrient concentrations in staple crops) is a recent strategy recommended for controlling Iodine Deficiency Disorders (IDDs). However, its success inevitably depends on stakeholders’ appreciation and acceptance of it. By taking Northern Uganda as a case, this study aimed to capture and compare the perceptions of seven key stakeholder groups with respect to agronomic iodine biofortification. Therefore, we employed a SWOT (Strength, Weaknesses, Opportunities & Threats) analysis in combination with an Analytical Hierarchy Process (AHP). Findings show that stakeholders (n = 56) are generally positive about agronomic iodine biofortification in Uganda, as its strengths and opportunities outweighed weaknesses and threats. Cultural acceptance and effectiveness are considered the most important strengths while the high IDD prevalence rate and the availability of iodine deficient soils are key opportunities for further developing agronomic iodine biofortification. Environmental concerns about synthetic fertilizers as well as the time needed to supply iodine were considered crucial weaknesses. The limited use of fertilizer in Uganda was the main threat. While this study provides insight into important issues and priorities for iodine biofortification technology in Uganda, including differences in stakeholder views, the application of the SWOT-AHP method will guide future researchers and health planners conducting stakeholder analysis in similar domains.
Gene action conditioning resistance traits to spotted stem borer, Chilo partellus, in grain sorghum.
(International Journal of Tropical Insect Science, 2019-03-06) Muturi, P. W.; Mgonja, M.; Rubaihayo, P.
Understanding the mode of gene action conditioning traits of interest in sorghum is important for effective and efficient plant breeding programs. The objective of this study was to establish the nature of gene action for components that contribute to resistance to spotted stem borer, Chilo partellus, in grain sorghum. The experimental material consisted of seventeen sorghum lines with varying levels of resistance to C. partellus. Genetic analyses were performed using a line x tester method using Genstat statistical software. There was significant variation among the F1 for C. partellus resistance and grain yield. The general combining ability (GCA) for deadheart damage was significant (P ≤ 0.01) implying that this trait was governed by an additive type of gene action. Specific combining ability (SCA) for exit holes and stem tunneling were significant (P ≤ 0.01) suggesting that these characters were conditioned by both additive and non-additive types of gene action. Lines ICSA 472, ICSA 464, ICSB 474 contributed high levels of resistance to hybrids while IESV 93042 SH, IS 21879 and IESV 91131 DL were good sources of genes for high grain yield. This observation implied that grain yield and stem borer resistance traits should be considered in development of C. partellus resistant sorghum since a resistant line doesn’t necessarily yield high and vice versa. Generally, results of this study indicated that it would be possible to breed for high C. partellus resistance from this set of germplasm for cultivation by farmers in areas where the insect pest causes epidemics.
Near-infrared spectroscopy applications for high-throughput phenotyping for cassava and yam: A review
(International Journal of Food Science and Technology, 2021-08-01) Alamu, Emmanuel Oladeji; Karima, Meghar; Nuwamanya, Ephraim; Fabrice, Davrieux
The review aimed to identify the different high-throughput phenotyping (HTP) techniques that used for quality evaluation in cassava and yam breeding programmes, and this has provided insights towards the development of metrics and their application in cassava and yam improvements. A systematic review of the published research articles involved the use of NIRS in analysing the quality traits of cassava and yam was carried out, and Scopus, Science Direct, Web of Sciences and Google Scholar were searched. The results of the review established that NIRS could be used in understanding the chemical constituents (carbohydrate, protein, vitamins, minerals, carotenoids, moisture, starch, etc.) for high-throughput phenotyping. This study provides preliminary evidence of the application of NIRS as an efficient and affordable procedure for HTP. However, the feasibility of using mid-infrared spectroscopy (MIRS) and hyperspectral imaging (HSI) in combination with the NIRS could be further studied for quality traits phenotyping.
QTL Mapping of Traits Associated with Dual Resistance to the African Stem Borer (Busseola fusca) and Spotted Stem Borer (Chilo partellus) in Sorghum (Sorghum bicolor)
(International Journal of Genomics, 2021-01-18) Muturi , Phyllis W.; Mgonja, Mary; Rubaihayo, Patrick; Mwololo, James K.
Sorghum (Sorghum bicolor (L.) Moench) is an important food crop in semi-arid tropics. The crop grain yield ranges from 0.5 t/ha to 0.8 t/ha compared to potential yields of 10 t/ha. The African stem borer Busseola fusca Fuller (Noctuidae) and the spotted stem borer Chilo partellus Swinhoe (Crambidae), are among the most economically important insect pests of sorghum. The two borers can cause 15% - 80% grain yield loss in sorghum. Mapping of QTLs associated with resistance traits to the two stem borers is important towards marker-assisted breeding. The objective of this study was to map QTLs associated with resistance traits to B. fusca and C. partellus in sorghum. 243 F9:10 sorghum RILs derived from ICSV 745 (S) and PB 15520-1 (R) were selected for the study with 4,955 SNP markers. The RILs were evaluated in three sites. Data was collected on leaf feeding, deadheart, exit holes, stem tunnels, leaf toughness, seedling vigour, bloom waxiness, and leaf glossiness. ANOVA for all the traits was done using Genstat statistical software. Insect damage traits and morphological traits were correlated using Pearson’s correlation coefficients. Genetic mapping was done using JoinMap 4 software, while QTL analysis was done using PLABQTL software. A likelihood odds ratio (LOD) score of 3.0 was used to declare linkage. Joint analyses across borer species and sites revealed 4 QTLs controlling deadheart formation; 6 controlling leaf feeding damage; 5 controlling exit holes and stem tunneling damages; 2 controlling bloom waxiness, leaf glossiness, and seedling vigour; 4 conditioning trichome density; and 6 conditioning leaf toughness. Joint analyses for B. fusca and C. partellus further revealed that marker CS132-2 colocalised for leaf toughness and stem tunneling traits on QTLs 1 and 2, respectively; thus, the two traits can be improved using the same linked marker. This study recommended further studies to identify gene(s) underlying the mapped QTLs.
Population Dynamics of Fall Armyworm (Lepidoptera: Noctuidae) in Maize Fields in Uganda
(Insects, 2024-04-23) Ajam, Angella Lowra; Karungi, Jeninah; Ogwal,Geofrey; Otim, Michael Hilary
Spodoptera frugiperda (Lepidoptera: Noctuidae), commonly known as fall armyworm, was first detected in Uganda in 2016 and has spread to all the maize-growing districts. Different methods have been deployed to control this pest. However, there is a limited understanding of the role of the environment and farmers’ practices on the abundance of and damage by S. frugiperda in Uganda. This study, therefore, assessed the abundance of S. frugiperda and leaf damage levels in three different districts and explored the association between agronomic practices, crop phenology, and weather parameters on S. frugiperda damage and abundance in smallholder farmers’ maize fields using a longitudinal monitoring survey in 69 farmers’ fields of Kole, Kiryandongo, and Nakaseke for three seasons. The numbers of egg masses and adults were generally low. The highest numbers of adults were trapped in Kiryandongo, followed by Nakaseke, and the lowest numbers were trapped in Kole. Leaf damage and incidence of damaged plants differed significantly between districts and seasons. Leaf damage and abundance of larvae varied significantly in the districts and at different growth stages. Conservation tillage, reduced weeding frequency, increased rainfall and high maximum temperatures were associated with reduced S. frugiperda damage. No significant relationship was observed between pesticide or cropping systems with S. frugiperda leaf damage. However, the influence of fertilizer use on leaf damage was contradictory across seasons and districts. Timely and vigilant scouting, proper timing of control measures, and minimum tillage practices should be included in an IPM strategy for S. frugiperda.
Parasitoid Distribution and Parasitism of the Fall Armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) in Different Maize Producing Regions of Uganda
(Insects, 2021-01-29) Otim, Michael Hilary; Aropet, Stella Adumo; Kanyesigye, Dalton; Wee, Tek Tay
The fall armyworm (FAW) Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) has successfully invaded Africa, where it has significantly impacted maize and sorghum production. Management of FAW in Africa predominantly relies on synthetic insecticides, which are expensive, and negatively impact the environment and beneficial insects. We, therefore, conducted field surveys in Uganda in 2017 and 2019 to identify egg and larval parasitoids of FAW for possible use in integrated pest management (IPM) programs. Parasitoids were identified by their mitochondrial DNA cytochrome c oxidase subunit 1 (mtCOI) gene sequences. We identified 13 parasitoid species belonging to three families of Hymenoptera: Platygastridae, Braconidae and Ichneumonidae, as well as one Dipteran family (Tachinidae). Coccygidium spp. and Chelonus bifoveolatus were the most abundant and widely distributed parasitoids. Overall, parasitism averaged 9.2% and ranged from 3.1% to 50% in 2017, and 0.8% to 33% in 2019. Parasitism by Sturmiopsis parasitica, Diolcogaster sp., and Cotesia flavipes on FAW in maize crops are reported for the first time. Our results suggest high biological diversity of FAW parasitoids, which should be exploited in the IPM of the FAW in Uganda.
Assessment of end user traits and physicochemical qualities of cassava flour: a case of Zombo district, Uganda
(International Journal of Food Science and Technology, 2021-01-13) Nanyonjo, Ann Ritah; Kawuki, Robert Sezi; Wembabazi, Enoch; Hale, Tufan
Cassava breeding programmes in Uganda do not currently select materials based on flour making quality, explaining in part the low adoption rates of many released varieties. In this study, we describe end user trait preferences, processing qualities and physicochemical properties of cassava flour. We found that higher proportion of women than men showed preference for most attributes of cassava flour quality evaluated in this study. Preference for colour was 66% and 52% among women and men, respectively, while that for stickiness of Kwon was 26% (women) and 15% (men). Ease of peeling and stickiness of Kwon were key processing traits. Heap fermented flour had higher pasting temperatures, but lower viscosities than sun-dried flour, and had lower amylose content compared to fresh root starch. The results demonstrate the importance of gender sensitive participatory evaluation of breeding materials, in tandem with physicochemical evaluation during selection of best possible candidate breeding lines.

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