Uganda Journal of Agricultural Science (UJAS)
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Farmer participation in soil management research process: The case of Matugga farmers of Uganda
No full textWith the high rate of soil degradation in Uganda, research to address soil fertility problems has to involve farmers at all stages of the process as active participants. Farmers' participation is very important in identification of agricultural problems, their causes as well as potential solutions as farmers are knowledgeable of their farming systems. Experiments designed together with farmers to alleviate these problems are likely to be well based in reality and meaningful to farmers with high subsequent adoption rates. Therefore, farmer participation in research is important for the in tegration of farmers' knowledge, perceptions and skills with those of researchers, and is a learning process for both farmers and researchers which in the long run is hoped will enhance agricultural technology adoption. In case of Matugga village, farmers' perception of their soils, soil related problems and possible solutions to the problems were observed by the researchers. Indigenous technical knowledge of farmers in regard to their soils was a base for future research work on soil fertility management in the area
Firewood consumption around Budongo Forest Reserve in western Uganda
No full textWood fuel is renewable. but its consumption can be sustained when the rate of harvesting does not exceed the growtb rate. For a per capita firewood consumption of 0.7 m3 in Masindi and 0.6 m3 in Hoima District, age, sex, and family size. influenced the levels of fuelwood consumption. Willingness to participate in communal management of forest resources was influenced by gender and age. It is recommended that conservation of fuel wood resources should be encouraged by introducing efficient cooking stoves and other energy saving measures. In addition, communities should be encouraged and facilitated to plant woodlots so as to reduce their dependance on fuelwood resources from communal and government forest reserves
In vitro microtuberisation of two improved Ugandan Solanum potato varieties
No full textThe performance of explants derived from three and six week-old green house-grown potato (Victoria and Kisoro) mother plants was evaluated. The mother plants were fertilized with different combinations of nitrogen, phosphorus, and potassium fertilizers. Explants were cultured on modified Murashige and Skoog's(MS) basal salts, supplemented with appropriate vitamins and growth regulators, for shoot and microtuber induction. Microtubers were induced directly from nodal cuttings inoculated on tuberisation medium and from defoliated in vitro shoots previously grown on shoot propagation medium, before transfer onto the tuberisation medium. In vitro shoot length and node number were significantly (P<0.05) increased by sole N application and retarded by sole P, or K application. Application of N along with P or K showed intermediate effects, but improved shoot growth. Single N application was inimical to microtuber forn1ation, whereas P and K promoted early tuberisation, characterised with significantly (P<0.05) laql'e diameters and fresh weights. Victoria produced bigger and fewer microtubers than Kisoro. Increased number of micro tubers occurred due to combined application ofN,P and K. Microtubers derived from defoliated in vitro shoots showed no significant (P>O.OS) difference in size due to mother plant pre-treatment, unlike the number of microtubers per explant. The six week-old nodal cuttings barely regenerated (5-15%) on the tuber induction medium, and had 30-70% regeneration on shoot induction medium. Better regeneration (60-70%) occurred in theN fertilized mother plants than with P and K (30-50%). Microtubers derived from defoliated in vitro shoots. irrcspecth·e of genotype and pre-treatment produced very few, tiny microtubers and others did not tuberize. Attempts to chemically break dormancy using gibberellic acid gave eratlc results. No significant variation was observed between the conventional mother clones and the in vitro cultures and microtubers
Park resources use and user attitudes towards conservation in Kibaie National Park, western Uganda
No full textNo Abstrac
Logging, arboricide treatments and regeneration at Budongo Forest, Uganda
No full textA study was carried out to detect whether logging and arboricide treatments had influences on floristic composition of fourcompartments in Budongo Forest, Uganda. The compartments were (N15) which had never been logged or treated; B4)logged 50 years; N4 logged 40 years, and W2I logged 30 years ago. The species treated were Ficus species, Alstonia booneiand Cynometra alexandri. In addition to arboricide treatment logging was mainly on trees of the meliaccae family. Datawere collected from 16 points in each compartment and gradient of variation were identified using the stand tables for eachcompartment. Results were compared with Eggeling's plot data collected at Budongo 50 years ago. It was found thatlogging affected the forest structure, and the floristic composition was influenced by the succession state at the time oftreatment Furthermore, variation in the forest was not readily related to the time of logging/arboricide treatment. Despitethe treatments, the residual stands retained the general character of the pre-exploitation forest and in the ensuing time theyall assumed broadly similar comrositions. The most distinct (compartment B4) still showed features of colonising forestwhich were much fess evident in others. The control compartment (N15) was still different; it contained more forest treeindividuals of secondary species than any of the other compartments. This suggests that Eggeling's time scale for the forestsuccession, and perhaps even his successional assumption should be reconsidered
Changes in the viscosity and energy density of weaning maize porridge on supplementation with groundnut paste and dairy milk
No full textThe effect of replacing 25% of the basic maize flour with groundnut paste (w/w) and/or 10% of the liquid ingredients with fresh dairy milk (v/v) on the viscosity and energy density of weaning maize porridge was investigated in a 2• fractional factorial experiment. Other factors investigated included (i) particle size of the flour (ii) concentration of the porridge (iii) cooking time (iv) the temperature of the porridge at the time of viscosity measurement and (v) the shear speed and shear time of the viscometer during viscosity measurements. The viscosity of the porridge was measured using 1 rotational viscometer while its energy density was determined by calculation from the proximate values of the raw ingredients. The results showed a significant reduction in the viscosity of the maize porridges due to addition of groundnut paste (P<0.001) or fresh dairy milk (P<0.001). Overall, ground nut alone decreased the viscosity of the porridges by 56. 1%, milk alone by 26.0% and groundnut plus milk by 64.9%. The influence of the addition of groundnut on the viscosity of the porridges was significantly influenced by concentration of the porridge (P<0.001), shear speed (P<0.01), cooking time (P<0.025) and flour particle size (P<0.05) with groundnut reducing the viscosity more at higher concentrations, lower shear speeds, higher cooking times and with fine particle-sized flour. The influence of addition of dairy milk on the viscosity of the porridges was significantly influenced by concentration (P<0.001) and flour particle size {P<0.05) with milk reducing the viscosity more at higher concentrations and with fine particle-sized flour. The energy density of the porridges was substantially increased by addition of groundnut alone (11.5%), milk alone (25.0%) and groundnut plus milk (36.4%). These results indicate that the viscosity of weaning maize porridges can be reduced and the energy density increased by supplementation with groundnut paste and/or dairy milk. As energy deficit has been found to be the most significant factor in the aetiology of protein-energy malnutrition (PEM), it is therefore recommended that weaning cereal porridges should be supplemented with energy-rich foods
In-ground post maturity storability of five local sweetpotato varieties
No full textTwo experiments are described in which prolonged post maturity storability of sweetpotato (lpomoea batatas L.) was studied between 1990 and 1992 at Namulonge Agricultural and Animal Production Research Institute (NAARI). Five commonly grown local varieties Tanzania (TZ), Tororo I (TOR l), Tororo 3 (TOR 3), Kawogo (KA} and Kyebandula (KY) were harvested at 4, 5, 6, 7, 8, 9 and 10 months after planting (MAP). The harvest date (HD) for optimum storage root yieldsfor for varieties TZ, TOR I, KA and TOR 3 were at 8 MAP while that for KY was 9 MAP. Varieties KA and KY attained their optimum fresh root yield at 10 MAP while varieties TOR 3, TOH I and TZ attained theirs at 7, 8 and 8 MAP, respectively. Storage root quality varied among varieties and deteriorated with time for all varieties. The magnitude of weevil damage increased with increase in in-ground storage period, but remained relatively stable after 9 MAP. The different varieties correlated differently but not significantly with the level of weevil damage except TZ ( r= -0.88*). The dry matter content percent (DMC %) varied among varieties and was negatively but non significantly correlated with rainfall. In-ground post maturity period had no significant effect on root cooking quality, taste and texture. However, the optimum HD is crucial if optimum economic yield is to be achieved
Life cycle and population growth of the maize aphid on potted finger millet plants
No full textNo Abstrac
Fishing gear selectivity for Lates niloticus L., Oreochromis niloticus L. and Rastrineobola argentea P. in Lakes Victoria, Kyoga and Nabugabo
No full textCatch effort data on which fisheries management regulations are sometimes based are not available for most lakes in Uganda. However, failure to regulate fishing gears and methods has been a major cause of collapse of fisheries in the country. Fisheries hiwe been damaged by destructive and non-selective fishing gears and methods such as trawling and beach seining, by use of gill nets of mesh size which crop immature fish and by introduction of mechanised fishing. Selectivity uf gears used to crop Lates niloticus L(Nile perch), Oreochromis niloticus L. (Nile tilapia) and Rastrineobola argentea Pellegrin (Mukene) which lire currently the most important commerc ial s pecies in Uganda were exam ined in order to recommend the most suitable types, sizes and methods that should be used in exploiting these fisheries. Gill nets of less than 127 mm mainly cropped immature Nile tilapia and Nile perch. To protect these fisheries, the minimum mesh size of gill nets should be set at 127 mm. Seine nets of 5 mm caught high proportions in immature Mukene while those of 10 mm caught mainly mature Mukene. When operated inshore, both sizes caught immature Nile perch and Nile tilapia as by-catch. To protect the Mukcne fishery and avoid catching immature bye-catch, a minimum mesh size of the Mukene net should be 10 mm operated as Lam para type net offshore, but since most fishermen have been using S mm seine nets for over five years the minimum size should not be allowed to drop below 5 mm pending further thorough investigations. Beach seining and trawling are destructive to fisheries and should be prohibited until data that may justify their use is available
Efficacy of some cu.ltural management methods on Callosobruchus chinensis (L) infestation during storage of pigeonpea seed
No full textStudies were conducted at Kawanda Agricultural Research lnstiuite to determine the efficacies of three storage practices viz: traditional mud-straw-cowdung silo " tua" storage, pod storage and storage of split seeds, on the management of Callosobruchus chinensis infestations in dried pigeon pea seeds. Lowest pigeonpea seed infestation was observed in sealed "tua", followed by loosely covered "tua" (2,512 insects and 3.81% seed damage), and the highest in .sack stored pigeonpea. Higher temperatures were observed in the " tua" (scaled " tua" 36.2°C, loosely covered "tua" 31.8°C) than in sack storage (25.5°C). Seed viability was also higher in " tua" (sealed 72.7% , loosely covered 76.3%) than in sack stored seeds (35.0%). Pod stored pigeonpea was effective in controlling C. chinensis populations, with infestation and seed damage of only 3.9 insects (all dead) and 0.04% respectively, compared to 45,000 insects and 19.8% respectively, in seed stored trials. Pod stored pigeonpea also ma intained higher seed viability (85.8%) than sack stored pigeonpea (45.1 %). Pigieonpea splitting depressed infestation by C. chinensis, reducing pest numbers, from 320 insects on the first month of storage to 10 insects on the third month. Whereas in whole stored seeds, there wns a sharp rise in pest population from 900 in first month of storage to over 10,000 on third mouth