Uganda Journal of Agricultural Sciences

Effect of dormancy breaking treatments on Corchorus olitorius L. accessions

2025-05-02T14:22:53+00:00

Corchorus olitorius is an indigenous leafy vegetable, which is rich in nutrients and is used for food preparations in low-income households in Africa. However, its cultivation is deterred by delayed seed germination, due to its hard seed coat. The objective of this study was to assess the effect of different dormancy breaking methods on enhancing seed germination of Corchorus olitorius accessions. The experiment was conducted at the CSIR-Plant Genetic Resources Research Institute, Bunso in the Eastern region, Ghana. Seeds of six Corchorus olitorius accessions were subjected to four dormancy breaking treatments, which include no soaking, soaking in pure water for 24 hours; and soaking in hot water for 30, or 60 seconds at 90 OC. Parameters measured include seed vigour, germination percentage, plant height (cm), number of branches per plant, pod length (cm) and number of seeds per pod. Significant differences (p<0.001) were observed in seed vigour and germination percentage among the six Corchorus olitorius accessions subjected to all dormancy breaking treatments. The highest seed vigour was observed in accession GH10126 soaked in hot water for 30 seconds. The no soaking treatment of accessions GH10070, GH10126 and GH10441 had the lowest vigour. The highest germination percentage was observed in accession GH10308 soaked in hot water for 60 seconds. Corchorus olitorious seeds treated with hot water at 90 OC for 30 or 60 seconds, performed normally with regards to growth and yield when established under field conditions.

Inheritance of multiple resistance to fungal diseases in tropical maize germplasm

2025-05-24T09:11:32+00:00

Maize (Zea mays L.) ear rots caused by Aspergillus flavus, Fusarium graminearum and Stenocarpella maydis affect grain quality and are associated with mycotoxins that pose precarious food and feed safety issues. The objective of this study was to determine the inheritance of multiple resistance to major fungal pathogens (Aspergillus flavus, Fusarium graminearum and Stenocarpella maydis) in maize in the tropical Africa. A total of 30 tropical inbred lines with varying resistance to A. flavus and both F. graminearum and S. maydis, were mated in a North Carolina II Design and the progeny consisting of single crosses, test crosses and their parents evaluated for single infection and yield performance. Resistance to the three ear rot pathogens and grain yield was found to be inherited independently. Therefore the three fungal infections had low or negligible effect on grain yield, though adversely reduced the grain quality. Multiple resistance to the three ear rot pathogens was majorly additive in nature. Some non-additive gene effects like dominance and epistasis could be contributing to multiple ear rot resistance. Maize hybrid vigour was found to enhance ear rot resistance.

Implications of farm succession plans on sustainable poultry productivity in Oyo State, Nigeria

2025-05-21T16:25:00+00:00

The significance of farm succession planning in sustaining smooth transitioning longevity of family farm operations, especially with the overly ageing farming population in sub-Saharan Africa (SSA), cannot be over-emphasised. The objective of this study was to examine the implications of farm succession plans on sustainable poultry productivity in Oyo state, Nigeria. A multi-stage sampling procedure was used to select 260 respondents (108 poultry farmers and 152 farmers’ children who were between 15 and 25 years old), for the purpose in Egbeda and Oluyole Local Government Areas of Oyo State, Nigeria. Data were obtained using a questionnaire, which was administered through interview schedules. Most (86%) of the farmers had at a point or the other considered the succession of their farm. Results of an Ordered Logistic Regression showed that poultry farmers’ succession plans were significantly influenced by farming status (part-time or full-time) (=1.455; z=1.95), stock size (=2.089; z=2.83), Generational Integration Process (=4.049; z=6.00), gender of farmer (=1.012; z=1.65) and profitability of farm over the last three years (=0.036; z=1.75). From the children (potential successors) stand point, personal interest (z = 1.71), number of siblings (z=-3.01) and farm profitability in the last three years (z=3.63), had significant influence on their disposition towards farm succession. Age (z= -0.45), gender (z= 1.01), birth order (z= -0.66), parent’s education level (z=0.38) of potential successors, did not have significant effects on their disposition towards farm succession. Profitability of the farm business was a major factor in farm succession on the part of both farmers and potential successors. Results suggest that more females should engage in poultry business and farmers should adopt GIP for farm succession.

Genetic variability in juvenile growth traits of Ugandan indigenous chicken populations raised under an intensive deep litter system

2025-05-22T19:11:18+00:00

Uganda’s indigenous chickens (IC) display significant phenotypic diversity in body weight (BW) and growth performance. However, there has been no study on the genetic diversity related to juvenile BW and growth performance in indigenous chicken populations (ICP), to support early selection of improved growth performance. The objective of this study was to assess the genetic variation in chicken juvenile BW and growth among selected ICP in Uganda. Three populations of IC were sourced from Apac, Lira and the National Semi-Arid Resources Research Institute (NaSARRI), as founder populations. Chicks were hatched from founder eggs, wing-banded and reared under identical conditions, in a deep litter system. Body weight was recorded weekly from hatch to four weeks of age. Hatch weight was higher (P<0.01) for Apac and Lira birds compared to NaSARRI. Mean Daily gain (ADG) was greatest for Lira and lowest for NaSARRI birds. The mean relative Growth Rate (RG) of chicks from Lira and Apac was comparable, but both were greater (P<0.05) than for NaSARRI. Broad-sense heritability estimates for BW0, BW1, BW2, BW3, and BW4 were 0.35, 0.50, 0.54, 0.47, and 0.56, respectively. Genotypic variances for BW measurements varied (P<0.05) among the ICP. The heritability estimates for ADG and RG were 0.41 and 0.49, respectively, with genotype variances differing significantly (P<0.01) across the ICP for both ADG and RG. These results demonstrate both phenotypic and genotypic variability in juvenile BW and growth performance. Moderate heritability and positive phenotypic correlations suggest that these traits can be effectively improved through selective breeding.

Developmental biology of Bean Leaf Beetle (Ootheca mutabilis) on common bean

2025-06-26T17:33:51+00:00

Common bean (Phaseolus vulgaris L.) is a major source of food and income for people in sub Saharan Africa. Attack by Bean Leaf Beetles (Ootheca spp. Chev.) is one of the major causes of yield loss to the crop, causing up to 48.9% grain yield loss. Despite the damage, there is limited information on the biology, including preferred oviposition sites and development, of Ootheca spp. This information provides strategic entry points to potential control interventions. The objective of this study was to investigate the oviposition and development duration of O. mutabilis, which is the most abundant and damaging species of Ootheca on common bean in Uganda. A screenhouse study was conducted during 2019, using the common bean variety, NABE 16. Parameters monitored included type of oviposition sites, egg cluster size, and morphological changes and development duration for each stage. The beetles preferred to lay clustered eggs than singly, and oviposited in crevices or cover surface, and near plant stalks or roots, which protects the eggs and ensuring the neonates easily find their food. Development of O. mutabilis took 120 days with the larval stage lasting the longest; followed by pupae and eggs at 75, 24 and 22 days, respectively. This long biological cycle of the beetle goes beyond that of most common bean varieties of the bush type, implying that juvenile stages of the beetles remain in the soil after bean harvest. As a management strategy, we recommend rotation with non-host crops such as maize in order to break the biological cycle of the beetles, and open tillage to expose the beetles in the soil to extreme weather and natural enemies. Further studies will be needed on the fertility, longevity and diapause mechanisms.

A decade of collaboration on anti-tick vaccine research between SaBio-IREC-Spain and National Agricultural Research Organization-Uganda

2025-06-30T16:57:08+00:00

These results are the outcome of ten years of collaboration between the Health and Biotechnology (SaBio) group at the Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM), Spain, and the National Agricultural Research Organization (NARO), Uganda. The collaborative project evolved from initial controlled pen trials using a personalized vaccinology approach to develop an effective Subolesin- based vaccine against multiple cattle tick species, to field trials evaluating the vaccine’s efficacy, effectiveness, and safety. Ultimately, the collaboration led to the successful transfer of vaccine production technology to Uganda. This partnership demonstrates how the challenge of limited access to biotechnological products in Sub-Saharan Africa can be addressed through sustained international cooperation.

Mitochondrial DNA diversity of Tanganyika Shorthorn Zebu cattle in Tanzania

2025-07-08T16:33:55+00:00

Indigenous cattle of sub-Saharan Africa exhibit high phenotypic variability, which in part is due to influence of environmental factors to which they have been exposed during their evolution. Analysis of genetic diversity at molecular level is essential for making informed decisions regarding choice of potential sub-populations for breeding and conservation. The objective of this study was to analyse genetic diversity of Tanganyika Shorthorn Zebu cattle in the Lake Victoria Basin area, which harbours a large indigenous cattle population in Tanzania. A total of 25 cattle of Sukuma and Tarime strains from Misungwi and Maswa Districts were genotyped by targeting 1200bp of mtDNA D-loop. Resulting sequences were used to estimate genetic diversity indices, analyse haplotype network and construct a Maximum-Likelihood Tree. Both sub- populations revealed high genetic diversity, with few individuals (8%) showing admixture between them. TheTarime strain tended toretain more genetic diversity than the Sukuma strain; and thus recommended as a target sub-population for selective breeding and genetic conservation of Tanganyika Shorthorn Zebu cattle in the Lake Victoria Basin of Tanzania. Further population genetics studies for indigenous cattle employing highly detective haplotype analysis tools are recommended in the area to clarify if the genetically divergent haplotypes observed could be a different sub-species or strain.

Occurrence of Kariba weed on selected water bodies in Uganda

2025-08-04T11:55:49+00:00

Kariba weed (Salvinia molesta D.S. Mitch.) is a floating aquatic fern that has devastated aquatic production systems worldwide. The objective of this study was to establish the status of occurrence and infestations levels of the weed on the water bodies in Uganda. The study was conducted on purposefully selected water bodies in Uganda, over a period of 2018 to 2022. Kariba weed occurred at varying infestation levels on all water bodies in the country, except on Lake Bisina. The highest number of daughter plants (732 plants per 0.25 m2 quadrant) was registered at Kajjansi, along Lake Victoria. The main impacts of the weed on the water bodies were obstruction of fishing and water transport; and reduced water quality. Given that Kariba weed is dispersed by water currents and vegetatively spread by boats and fishing gears, a catasptrophe in terms of dysfunction of the productivity of the country’s water resources is eminent. Biological control of Kariba weed using Cyrtobagous salviniae weevils is recommended to sustainably manage this devastating water weed.