Uganda Journal of Agricultural Science (UJAS)
Not a member yet
415 research outputs found
Sort by
Strategies for management of animal genetic resources in Uganda
Get PDFUganda has 6.3, 6.8, 1.1, 1.7 and 32.6 million cattle, goats, sheep, pigs and poultry, respectively (MAAIF, 2002). Livestock are a major component of the agricultural GDP, contributing 17% (MAAIF, 2002). Livestock are a major source of income and security for large number of resource-poor households
Evaluation of potential sources of inoculum for the coffee wilt epidemics in Uganda
Get PDFStudies were conducted at Coffee Research Institute (CORI) to determine various sources of inoculum for Fusarium xylarioides (F.X), the causal agent of coffee wilt disease (CWD). Coffee seedlings of between 5-6 months were inoculated with F. xylarioides spores obtained in situ from perithecial stroma around the bases of infected coffee trees. F. xylarioides inoculum raised in culture initially obtained from infected coffee tissue was also used. Furthermore, an attempt was made to isolate F. xylarioides from the stalks of the coffee berries/seeds. Results suggest that disease was higher on seedlings inoculated with spores from perithecial stroma than inoculum raised under laboratory conditions from infected coffee tissue. Inoculation by root dip in spore suspensions gave highest disease incidence of up to 100% and was the most effective. In all cases where inoculation was done on leaves, no coffee wilt disease symptoms developed. However, when stems were inoculated by pricking above the level of the fourth leaf, wilt symptoms were observed only on the upper section and none on the lower. The section below the point of inoculation continued to produce healthy tillers even 100 days after inoculation. The studies concluded that F xylarioides spores collected from infected
coffee stems and inoculated in situ cause CWD and these together with infected coffee stalks could be the avenues through which the pathogen spreads
Evaluation of cocoa introductions (Theobroma cacao L.) on Ddamba island, Mukono district
Get PDFElite seed of Trinidad Selected Hybrids and Costa Rica introductions of cocoa were planted in 1987 and quarantined on Ddamba island in Lake Victoria, Mukono district. There was no consistent evaluation of these materials for the initial 10 years because of lack of funds. With availability of funds from USAID/ IDEA, cocoa research was revived at Coffee Research Institute (CORI) and the Ddamba materials evaluated from 1999 to 2001. At the beginning of the evaluation only 1 tree of Trinidad Selected Hybrids, 90 trees of Costa Rica introductions, and 164 trees of local materials were surviving. No new disease or insect pests were observed on the introductions but just like the locals, they were affected by the major diseases and insect pests found on cocoa in Uganda. The major diseases found were pod rot (Phytopthora sp), and the insect pests were scales, mealybugs, aphids, lepidoptera, mites and vertebrate pests such as monkeys and squirrels. There were 11/2 times more trees among Costa Rica introductions bearing over 40 pods/tree as compared to the locals. However neither the parents nor the progeny of the introductions could be identified. Since it was apparent that the Costa Rica introductions might have good qualities, the seeds of these materials are being propagated in the nursery at the Coffee Research Institute
The P2 adenosine transporter as an indicator of drug resistant Trypanosoma brucei
No full textWe have analysed the Trypanosoma brucei gene TbAT1, which codes for the P2 adenosine transporter, to investigate a possible link between the presence of mutations in this gene and trypanocidal drug resistence. About 70% of T .b. gambiense isolates from a focus in North Western Uganda with high treatment failure rates following mclarsoprol therapy had a mutations within TbAT1. Unexpectedly, all individual isolates contained the same set of nine mutations in their TbAT1 genes. Identical sets of mutations were also found in a multi-drug resistant T.b.rhodesiense isolate from South Eastern Uganda and in a T.b.gambiense isolate from a relapsing patient from Northern Angola. Quantitative analysis of isolates from North western Uganda revealed that mclarsoprol relapse patients have significantly more infections with mutant TbATl (c2 = 6.70; d.f = 1; p = 0.0097, two tailed). Genetic knock out of TbAT1 of bloodstream trypanosomes did no affect in vitro cell proliferation, as well as mouse infectivity. However, the cells were rendered up to four times less susceptible to mclarsoprol. mclarsene oxide, and diminazene aceturate. In vivo experiments revealed that mouse infections of TbAT1 knock out clones could not be treated with four injections of 2mg/kg melarsoprol, while the same dose cured all the animals infected with the wild type clone. We conclude that loss of P2 transport activity significantly contributes to the increased drug resistence in African trypanosomes
Competitive ELISA: its validation and use in monitoring Contagious Bovine Pleuropneumonia (CBPP) antibody in Mbarara District.
Get PDFDiagnosis is of CBPP presents one of the major difficulties in the control of the disease. As a way of improving diagnosis, a competitive ELISA has been developed and a study was carried out to test, validate, and assess its field performance. A cross-sectional epidemiological sero-survey was carried out in Bukanga and Isingiro counties of Mbarara district, to determine the pre-study prevalence of CBPP in the two counties. Cluster sampling based on villages as well as multistage, purposive and simple random sampling were used in site selection. For analysis, blood samples were collected from 10% of all the presented herds. Epidemiological data were collected for herd and individual animals. All animals sampled were examined clinically for signs of CBPP. Our findings indicate that sero-prevalence by ELISA was always higher than that by CFT, which confirmed the epidemiological status of the study locations that were first obtained through focus group discussions. The graphical illustrations of the distribution of the negative and positive populations depict normal distribution hence a good laboratory performance of the test. Results from this study indicate that the relative specificity of c-ELISA is satisfactory when results are interpreted at the individual animal level
Factors affecting diversity of Dioscorea species in Uganda
Get PDFThe effects of drought, famine, distribution of land races, pests and diseases, deforestation, over-cultivation, introduction of new high yielding Dioscorea varieties, change in economic base, change in consumer preference, change in land use, status of transmission of indigenous knowledge and agricultural modernization on the diversity of Dioscorea were investigated in nine districts of Uganda. Three approaches were used: extensive eco-geographical survey, exploration and physical assessment. A structured questionnaire was used to capture information from the farming communities, government offices and local opinion leaders on the status of the yam in relation to farmlands, open countryside, protected areas and government departments in the nine target districts. Out of the 14 species recorded in Uganda the study showed that only seven species were available in the target areas. These included D. alata, D.dumetorum, D. odorotissima, D. bulbifera, D. rotundata, D. quartiniana, and D. schitnperianana. Reduction in the diversity of the yam was due mainly to serious genetic erosion at both inter- and intra-specific levels. Genetic erosion was mainly caused by lack of efficient propagation techniques, famine, pests, diseases, deforestation and lack of adequate promotion of the crop by the formal sector. The role played by the factors identified is discussed and recommendations for minimizing genetic erosion are given
Development and evaluation of motorized maize shelter
Get PDFProduction of maize in Uganda has constantly been increasing since 1991. The bulk of the crop is shelled using traditional methods, which cause high drudgery, and results into products of low market value. According to the Participatory Rural Appraisal survey conducted in 1995 by Agricultural Engineering and Appropriated Technology Research Institute. AEATRI. lack of appropriate maize sheller was identified among factors that impair this positive production trend. Following the survey, AEATRI embarked on developing a motorised maize sheller with a view to solving this problem. A proto-type w as designed, fabricated and tested on-station. This did not give expected results. It was bulky with low throughput (670kg/hr) and rather expensive. Major changes were made in its shelling mechanism to produce the second proto-type. This was tested both on-station and on-farm mainly with Longe-I maize variety. There was significant improvement in performance. Its output was 1 ton/hr of clean grain and fuel consumption was 1 It/ton of clean grain. This proto-type was further improved. The on-station and on-farm tests on the third proto-type using Longe-I maize variety yielded satisfactory results with an output of 1.25 tons/hr ofclean grain with a fuel consumption of 0.77 lt/ton ofclean grain. Shelling efficiency was 99.7% and unbroken grain was 2%. After these tests, the institute has recommended that the third proto-type may now be released for mass production
Potential of improved banana cultivars as a food security and income generating crop: preliminary results on adoption of the cultivars
Get PDFThe East African Highland banana, an important stable food in Uganda, is susceptible to weevils, black Sigatoka and nematodes. Host plant resistance has been identified as the most appropriate solution to these problems and selection of resistant clones from introduced germplasm adopted as one of the means of developing the intervention. Eleven promising clones selected from foreign introductions were evaluated in 13 districts of Central Eastern and North Eastern Uganda. The farming communities evaluated the clones for cooking, roasting, juice extraction and dessert qualities. Five of the clones were selected on the basis of bunch size and use. They noted that although the new bananas were not as good in taste as the East African Highland banana they were as good as other starchy foods in their areas. The introduced bananas were acclaimed for the advantages of being higher yielding than all the food crops known to the farming communities. The selected clones are currently diffusing fast in the areas. This paper describes the progress to date on promotion and diffusion of the selected clones
Water hyacinth, Eichhornia crassipes: A case of successful Biological Control in Lakes Kyoga and Victoria - Uganda
Get PDFWater hyacinth, Eichhornia crassipes, a world known water -weed was until lately serious a problem in Uganda and indeed the entire East African region. The weed caused serious socio-economic impact on the livelihood of Ugandans. Attempts were made to control the weed through an integrated approach including two biological control weevils, Neochetina bruchi and N. eichhorniae that were integrated in the control effort. Five years after their introduction, the weevils successfully reduced the biomass of the weed to an insignificant problem and life is back to normal in and along the formerly heavily affected lakes, Victoria,
Albert and Kyoga. The significance of this operation is discusse
Management of nematodes in banana systems in Uganda
Get PDFObservations from a screen house experiment to study the host status of cassava and sweet potato to the banana nematodes indicate that both cassava and sweet potato are nonhosts of the major banana nematodes, namely, Radopholus similis, Helicotylenchus multicinctus and Pratylenchus goodeyi. An experiment aimed at devising cropping sequences that would minimise nematode damage and enable acceptable levels of banana production to be maintained was designed. Banana nematode population densities declined to negligible levels after 13 months of a break-crop of cassava or sweet potato planted immediately after a nematode infested banana crop in on-station field experiment. Most farmers opted for the cassava break-crop when thetrialwasrepeatedon-farm at a site in Kayunga district. Populations of R. similis reduced to zero while those of H. multicinctus reduced to negligible levels within 10 months after planting the cassava break-crop. Fi om these studies, a banana-cassava-sweet potato-banana rotation, use of clean banana planting material and proper crop, soil and water management practices are recommended for improvement and maintenance of banana production in plots previously infested by nematodes at high population levels