Faculty of Agricultural Sciences

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Abundance, distribution and effects of temperature and humidity on arthropod fauna in different rice ecosystems in Uganda
(Journal of Entomology and Zoology Studies, 2017) Kizito, Elizabeth B.; Masika, Fred Bwayo; Masanza, Michael; Aluana, Goncalves; Barrigossi, Jose Alexandre Freitas
The study on abundance, distribution and effects of temperature and humidity on arthropod fauna was conducted in smallholder rice farming areas in three agro ecological zones of Lake Victoria basin, Northern moist farmlands and Western Savannah grasslands in Uganda. Arthropods were collected using a standard sweep net and a total of 17 orders representing 13,272 arthropods were recorded from the three agro – ecological zones during the study. Most arthropod fauna were collected in Bugiri, Lira and Kasese respectively. The most abundant orders throughout the survey included Homoptera, Coleoptera, Hemiptera, Diptera, Hymenoptera and Orthoptera. While the least abundant included Dermaptera, Zoraptera, Phasmatoda, Mantodae, Embioptera and Neuroptera. All orders except Embioptera, Mantodae, Neuroptera and Phasmatoda were collected in all the three agro ecological zones. The orders Diptera (p = 0.0282), Hymenoptera (p = 0.0051), Lepidoptera (p = 0.0149), Odonata (p = 0.0356) showed a significant difference in abundance in the three agro – ecological zones. Temperature and humidity had a significant effect on the arthropod population for example Aranea showed a positive correlation in their abundance with increase in temperature in all the agro – ecologies
Amplicon Sequencing Identified a Putative Pathogen, Macrophomina phaseolina, Causing Wilt in African Eggplant (Solanum aethiopicum) Grown in Tanzania and Uganda
(Frontiers in Agronomy, 2024-01-03) Xiangming Xu; Ruth Minja; Elizabeth Balyejusa Kizito; Fekadu Dinssa; Greg Deakin; Pamela Nahamya Kabod; Asheri Kalala; Eliciana Kweka; Omary Mbwambo; Deusdedith Mbanzibwa; Hamza Msangi; Mildred Julian Nakanwagi; Tom Passey; Stuart Sentance; Godfrey Sseremba; Eleftheria Stavridou; Gerard J. Bishop
African eggplant (Solanum aethiopicum L.) is one of the most common traditional vegetables in Tanzania and Uganda, but its productivity is severely affected by wilt diseases caused by a number of pathogens. Plant stem and root samples were collected in several fields from many neighboring diseased and healthy plants of the Gilo group in Tanzania and from the Shum group in Uganda to identify putative pathogens causing wilt on African eggplants. Through amplicon sequencing of sampled diseased and healthy tissues, we identified putative causal pathogens for the wilt symptoms. Wilting of S. aethiopicum in Uganda is most likely caused by the bacterial pathogen Ralstonia solanacearum whereas, in Tanzania, wilt is most likely caused by the fungal pathogen Macrophomina phaseolina, infecting roots. Infection of stems by Fusarium solani may also contribute to the wilt symptoms in Tanzania. Further artificial inoculation under controlled conditions confirmed that M. phaseolina can cause typical wilting symptoms on S. aethiopcium genotypes. The discovery of different putative causal agents of wilt in the crop demonstrates the need for site specific etiological analysis of wilt before developing and implementing effective control methods. Further research is needed to confirm the results and develop appropriate management measures against specific wilt pathogens.
Antioxidant potential of the farmer preferred selections of Solanum aethiopicum vegetable consumed in central Uganda
(European Journal of Biological Research, 2018-03) Sekulya, S.; Nandutu, A.; Namutebi, A.; Ssozi, J.; Masanza, Michael; Kabod, B.; Jagwe, J. N.; Kasharu, A.; Rees, Deborah; Kizito, Elizabeth B.
In addition to the rich micronutrient value, indigenous vegetables are regarded as possessing medicinal attributes. The Solanaceae family has over 1000 species worldwide, with a number of indigenous species originating in Africa. The most popular leafy vegetable in Uganda is the Solanum aethiopicum (Nakati). The objective of this study was to determine the selected phytochemical attributes, chlorophyll content, moisture content andtotal antioxidant activity of the farmer preferred selections within the landraces of Solanum aethiopicum leafy vegetable in Uganda. Theantioxidant activity was achieved by screening the leaf extracts for their free radical scavenging properties using diphenyl picryl hydrazyl (DPPH) and ascorbic acid as standard. The ability of the extracts to scavenge DPPH radical was determined Spectrophometrically at 517 nm. The study showed that all the landraces had a high polyphenol and flavonoid content with SAS185/P/2015 containing the highest flavonoid content (3.16±0.06 mg QE/g fw). SAS1641/2015 showed the highest total polyphenol content of 7.79±0.27 mg GAE/g fw and also showed the highest vitamin C content. This contributed to the high total antioxidant activity of 2.79±0.01 and 5.43±0.02 mg AAE/g fw when using FRAP and DPPH methods respectively. SAS145/2015 presented the highest chlorophyll content of 19.69±0.01 mg/g dwb. All the landraces showed a high percentage moisture content that ranged from 82.66±0.35 to 84.21±0.48%. These results are of nutraceutical significance and hence confirm their usage as medicinal vegetables.
Approaches to the effective utilization of Haplochromis spp. from Lake Victoria. I. Chemical composition in relation to utilization
(Journal of Food Technology, 1984) Ssali, William Mamiima; Hanson, S. W.; Knowles, M. J.
There are over 150 species of the cichlid genus Huplochrornis in Lake Victoria constituting a major underexploited food resource. As an aid to the processing of the deepwater stock, chemical composition data were obtained for the whole fish (separated into weight groups) and for the head, viscera, flesh and residual portions separately. Data are reported for lipid content, fatty acid composition, crude protein, true protein, amino acid composition, ash and moisture content.
Assessment of cassava diversity in Uganda using SSR markers
(2004) Kizito, Elizabeth B.; Castelblanco, W.; Omara, J.; Bua, A.; Egwang, T.G.; Fregene, M.; Gullberg, U.
The genetic diversity and differentiation of 272 cassava landrace accessions collected in Uganda is assessed in this study. In addition to this, 20 Tanzanian material was included from a previous study of diversity in Tanzania, 20 material from the Ghanaian germplasm bank, 20 material from Guatemala and 18 from holdings at CIAT and IITA to represent the core collection from Latin America. All together 9 groups or samples, based on country of origin, were created to study genetic diversity and differentiation within each country and among countries. Using simple sequence repeat (SSR) markers, variation in allele frequency at many unlinked loci was used to estimate the parameters of genetic diversity and differentiation, and to estimate the strengths of various forces shaping them. SSR data was analyzed by GENSURVEY (Vekemans & Lefebvre,1997), FSTAT 2.9 (Goudet, 1995) and NTSYS-PC(Rohlf, 1993). Results affirm a genetic divergence between African and Latin American accessions. They also show a high genetic diversity and a low differentiation in the Ugandan accession. There is a substantial role played by the cassava mosaic disease (CMD) on cassava genetic constitution in respective districts.
Bean-Based Nutrient-Enriched Puffed Snacks: Formulation Design, Functional Evaluation, and Optimisation
(Food Science and Nutrition Journal, 2020-06-01) Tumwesigye, Kashub Steven; Natabirwa, Hedwig; Nakimbugwe, Dorothy; Lunga'ho, Mercy; Muyomba, John H.
School-age children frequently consume snacks. However, most of the snacks they consume are of low nutritional quality. The objective of this study was to develop a nutrient-rich and acceptable extruded bean-based snack, which could contribute to improve nutrient intake, especially for school-age children. Snack formulations developed from Roba1 beans, maize, orange-fleshed sweet potato, and amaranth mixtures and processed in a twin-screw extruder, were evaluated and optimised for nutritional, textural and sensory properties.
Cassava Biomaterial Innovations for Industry Applications
(Cassava Biomaterial Innovations for Industry Applications, 2021) Tumwesigye, Kashub Steven; Oliveira, Jorge C.; Namuwaya, Sheila; Sousa-Gallagher, Maria Jose
Breakthrough innovations can spur growth in the modern era industry to realise sustainability and high returns on investments. Nowadays, biobased innovations for application in diverse industry sectors are considered as future pillars to counter resource depletion and ensure positive environmental impacts. Cassava is a strong flagship biomaterial promoting solution for resource-efficient use and a green environment. Innovative industrial application of cassava biomaterials enriches literature, presenting cassava as a versatile and unrivalled crop that is cardinal for more sustainable environment and biodegradable industrial products. Work on novel cassava biomaterials, which are low-cost, unexploited and with zero competition for food supply, are included. Using an integrated sustainable process, it shows how to indirectly reduce waste streams, through their effective use, guaranteeing zero carbon footprints and acting as a non-traditional strategy for equilibrium atmosphere and active packaging systems. Applications of Cassava biomaterial in food, as food supplements and in packaging systems are also covered in this chapter.
Changes in Sensory and Quality Characteristics of S. Aethiopicum (Shum) and A. Lividus (Linn) Leafy Vegetables along the Supply Chain
(Science and Education Publishing, 2018-05) Apolot, Mary Gorret; Ssozi, Joshua; Namutebi, Agnes; Masanza, Michael; Kizito, Elizabeth B.; Rees, Deborah; Hedwig, Acham
Changes in sensory attributes of vegetables over time under different conditions have been reported, however, little has been done regarding profiling and assessing changes in sensory attributes of raw leafy vegetables particularly Solanum aethiopicum (S.) and Amaranthus lividus (L.). This study therefore fills an important knowledge gap of profiling sensory attributes and assessing changes in color, texture and appearance of S.aethiopicum and A.lividus leafy vegetables over time after harvest. A complete randomized design in a 3 ×3 factorial arrangement (each vegetable sample was subjected to three treatments (Time of the day) and three replicates) and data was collected by use of quantitative descriptive sensory analysis. Descriptive data was entered into Microsoft excel spread sheets, averages computed and graphs generated. The data was further subjected to ANOVA and a least significant difference test was used to compare means of samples for all attributes at 95% confidence interval. Correlation analysis using Statistical Package for Social Scientients’ (SPSS version 16.0) was also performed to assess relationship between sensory attributes. Descriptive sensory analysis results showed that all 9:00hrs samples were rated highly for each attribute compared to the 12:00hrs and 15:00hrs samples. ANOVA results for S. aethiopicum showed statistical significant (p<0.05) difference for all the attributes except for light green color of leaf stalk (p<0.05) whereas that for A. lividus showed significant differences for moist appearance, well spread appearance, smoothness and overall quality. Correlation results showed significant positive relationship (p<0.05) among attributes. This study observed that sensory attributes of leafy vegetables change with time after harvest andtraders are therefore encouraged to adopt local cooling systems to help preserve the sensory attributes of vegetables.
Compatibility Barriers Affecting Crossability Between Solanum aethiopicum and Its Relatives
(Scientific Journals (Nature), 2022) Namutosi, Winnie; Bulyaba, Rosemary; Nakanwangi, Mildred Julian; Buteme, Ruth; Sseremba, Godfrey; Kizito, Elizabeth Balyejusa
Reproductive barriers are single most important impediment in conventional breeding of Solanum aethiopicum (Shum and Gilo) and its relatives. This study investigated compatibility barriers between S. aethiopicum and its relatives. A randomized complete block design and a full diallel mating method were used to evaluate floral phenology and compatibility of six genotypes at different floral stages. Parameters assessed include; anthesis, anther dehiscence, stigma receptivity, among others. Results showed that most flowers in anthesis per genotype were counted at 8:00am. Overall mean number of open flowers differed significantly (P<0.001) and was highest for N11(n=13) and least for E12(n=3). Anther dehiscence varied significantly (P<.001) among floral stages. However, there was no difference among genotypes. All genotypes showed high pollen viability (> 80%) although they differed significantly (P<0.01). Stigma receptivity averaged highest (3.31) for N11 and least (2.31) for In1. All genotypes exhibited self-compatibility; N11 averaged highest for fruit set (67.93%), seed per fruit (82) and F1 germination (79%). Crosses revealed moderate compatibility (50%); highest fruit were in N4xN11 (71.97%), seed N11xA1 (56) and F1 germination inN11x N4 (76.3%) respectively. In the crosses where In1 was a female parent 80% incompatibility was observed at fruit set whereas73% of crosses where E12 was a female parent set fruits without seed. Female functioning may be a major factor in observed incompatibility between S. aethiopicum and its relatives. To harness the potential of S. aethiopicum relatives, N11 and N4 can be advanced as female parents in wide hybridizations.
A Computer Program for Modeling the Conversion of Organic Waste to Energy
(MDPI Open access publisher, 2011) Namuli, Rachel; Laflamme, Claude B.; Pillay, Pragasen
This paper presents a tool for the analysis of conversion of organic waste into energy. The tool is a program that uses waste characterization parameters and mass flow rates at each stage of the waste treatment process to predict the given products. The specific waste treatment process analysed in this paper is anaerobic digestion. The different waste treatment stages of the anaerobic digestion process are: conditioning of input waste, secondary treatment, drying of sludge, conditioning of digestate, treatment of digestate, storage of liquid and solid effluent, disposal of liquid and solid effluents, purification, utilization and storage of combustible gas. The program uses mass balance equations to compute the amount of CH4, NH3, CO2 and H2S produced from anaerobic digestion of organic waste, and hence the energy available. Case studies are also presented.
Distribution, Timing of Attack, and Oviposition of the Banana Weevil, Cosmopolites sordidus, on Banana Crop Residues in Uganda
(The Netherlands Entomological Society, 2005-06) Masanza, Michael; Gold, C.S.; Huis, A. van
Crop sanitation (removal and chopping of residue corms and pseudostems following plant harvest) has been recommended as a ‘best bet’ means of reducing banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), populations. However, it has been unclear when such practices should be carried out and what types of residues should be destroyed. Therefore, trials were conducted in Uganda to determine C. sordidus distribution, timing of attack, and oviposition on crop residues and growing plants. Assessments were performed in on-station trials on different aged standing and prostrate residues by destructive sampling. Similar data were collected from farmers’ fields maintained at low, moderate, and high levels of sanitation. In the on-station trial, oviposition occurred on up to 120- day-old residues, although most occurred within 30 days of harvest. In a second on-station experiment, oviposition on standing residues was not significantly affected by residue age. By contrast, oviposition on prostrate residues was two times higher on 4-week-old than on 2-week-old residues, while the number of larvae on 8-week-old residues was three times higher than on 2-week-old residues. The number of adults was twice as high on 16-week-old residues as that on 2-week-old residues for both prostrate and standing residues. Farmers’ fields maintained at high sanitation had 50% fewer eggs per residue than farms with low sanitation levels. In general, the number of immatures per residue was 50% higher on banana corms than on pseudostems. Numbers of larvae per residue were three times more abundant at low than at high sanitation levels. Residues in fields with high sanitation supported 50% fewer adults than residues in low sanitation fields. The results suggest that removal and splitting of corms after harvest is effective and practical in destroying immature growth stages of the pest and that such practices should be carried out soon after harvest.
Diversity and distribution of African indigenous vegetable species in Uganda
(Academic Journals, 2017-11) Kizito, Elizabeth B.; Masanza, Michael; Sseremba, Godfrey; Kabod, Nahamya Pamela; Kasharu, Apolo Katwijukye; Jaggwe, John Nkalubo
African indigenous vegetable species (AIVS) provide a means of livelihood to many urban and peri-urban dwellers in Uganda. It was thus deemed necessary to understand the existing diversity and distribution of the traditional African vegetable species as a basis for recommending conservation and utilization strategies against biodiversity loss. A field survey was conducted in the four major agro-ecological zones of Uganda to provide information on a recent abundance of the various AIVS. Results from the survey showed that the Solanaceae (43.4%), Amaranthaceae (15.5%) and Malvaceae (11.6%) were the most prevalent families out of seven different families encountered. Twenty-three (23) species, a number lower than that initially reported in literature and distributed unevenly in the different regions were identified. Majority of the species were the indigenous rather than introduced vegetable species. Firstly, the study is informative of the superior importance of Solanaceous species compared to other AIVS. Secondly, the survey results indicate that the AIVS are becoming increasingly more important in Uganda than their introduced counterparts since all the 43.4% that composed the Solanaceae majority were of indigenous type. Research efforts should be devoted towards improved variety development and germplasm conservation to prevent a possible biodiversity loss of the most important AIVS for increased household incomes and nutrient security among the resource-poor majority in Uganda and other sub-Saharan Africa countries
Draft genome sequence of solanum aethiopicum provides insights into disease resistance, drought tolerance, and the evolution of the genome
(Oxford, 2019-08) Bo Song; Yue Song; Yuan Fu; Elizabeth Balyejusa Kizito; Sandra Ndagire Kamenya; Pamela Nahamya Kabod; Huan Liu; Samuel Muthemba; Robert Kariba; Joyce Njuguna; Solomon Maina; Francesca Stomeo; Appolinaire Djikeng; Prasad S. Hendre; Xiaoli Chen; Wenbin Chen; Xiuli Li; Wenjing Sun; Sibo Wang; Shifeng Cheng; Alice Muchugi; Ramni Jamnadass; Allen Van Deynze; Huanming Yang; Jian Wang; Xun Xu; Damaris Achieng Odeny; Xin Liu
Background: The African eggplant (Solanum aethiopicum) is a nutritious traditional vegetable used in many African countries, including Uganda and Nigeria. It is thought to have been domesticated in Africa from its wild relative, Solanum anguivi. S. aethiopicum has been routinely used as a source of disease resistance genes for several Solanaceae crops, including Solanum melongena. A lack of genomic resources has meant that breeding of S. aethiopicum has lagged behind other vegetable crops. Results: We assembled a 1.02-Gb draft genome of S. aethiopicum, which contained predominantly repetitive sequences (78.9%). We annotated 37,681 gene models, including 34,906 protein-coding genes. Expansion of disease resistance genes was observed via 2 rounds of amplification of long terminal repeat retrotransposons, which may have occurred ∼1.25 and 3.5 million years ago, respectively. By esequencing 65 S. aethiopicum and S. anguivi genotypes, 18,614,838 single-nucleotide polymorphisms were identified, of which 34,171 were located within disease resistance genes. Analysis of domestication and demographic history revealed active selection for genes involved in drought tolerance in both “Gilo” and “Shum” groups. A pan-genome of S. aethiopicum was assembled, containing 51,351 protein-coding genes; 7,069 of these genes were missing from the reference genome. Conclusions: The genome sequence of S. aethiopicum enhances our understanding of its biotic and abiotic resistance. The single-nucleotide polymorphisms identified are immediately available for use by breeders. The information provided here will accelerate selection and breeding of the African eggplant, as well as other crops within the Solanaceae family.
The effect of cassava mosaic disease on the genetic diversity of cassava in Uganda
(Springer International Publishing, 2005) Kizito, Elizabeth B.; Bua, Anton; Fregene, Martin; Egwang, Thomas; Gullberg, Urban; Westerbergh, Anna
Cassava (Manihot esculenta) is a tropical crop that is grown in Africa, Latin America and Southeast Asia. Cassava was introduced from Latin America into West and East Africa at two independent events. In Uganda a serious threat to cassava’s survival is the cassava mosaic disease (CMD). Uganda has had two notable CMD epidemics since the introduction of cassava in the 1850s causing severe losses. SSR markers were used to study the effect of CMD on the genetic diversity in five agro-ecologies in Uganda with high and low incidence of CMD. Surprisingly, high gene diversity was detected. Most of the diversity was found within populations, while the diversity was very small among agro-ecological zones and the high and low CMD incidence areas. The high genetic diversity suggests a mechanism by which diversity is maintained by the active involvement of the Ugandan farmer in continuously testing and adopting new genotypes that will serve their diverse needs. However, in spite of the high genetic diversity we found a loss of rare alleles in areas with high CMD incidence. To study the effect of the introgression history on the gene pool the genetic differentiation between East and West Africa was also studied. Genetic similarities were found between the varieties in Uganda and Tanzania in East Africa and Ghana in West Africa. Thus, there is no evidence for a differentiation of the cassava gene pool into a western and an eastern genetic lineage. However, a possible difference in the genetic constitution of the introduced cassava into East and West Africa may have been diminished by germplasm movement
Effect of Different Processing Conditions on Proximate and Bioactive Contents of Solanum aethiopicum (Shum) Powders, and Acceptability for Cottage Scale Production
(Science and Education Publishing, 2018-04) Akanyijuka, Sam; Acham, Hedwig; Tumuhimbise, Gaston; Namutebi, Agnes; Masanza, Michael; Jagwe, John N.; Kasharu, Apolo; Kizito, Elizabeth B.; Rees, Deborah
The purpose of this study was to investigate the effects of different processing conditions for production of dried Solanum aethiopicum (S.) leaf powder by comparing solar drying and cabinet drying processing techniques. Four (4) pre-treatments were done on S. aethiopicum leaves to inhibit enzyme action and prolong storage life. Treatments included dipping in; 10% saline solution, 10% vinegar solution, water (as the control), and steam blanching; done for both whole and sliced S. aethiopicum leaves. Each of the resultant samples were dried in both solar and cabinet dryers for a period of 24 hours. The dried leaf samples were grounded into powder using a coffee grinder and subjected to different laboratory analyses including; catalase activity, moisture content, vitamin C retention capacity and phytate content analyses. The results obtained were analysed using MINITAB version 16.0 at 5% significance level. The results showed that there was a reduction in catalase activity after pre-treatment and drying from 5.0±0.0 cm3 for the fresh un-treated leaves to a range of 4.5±0.7 – 3.0±0.0 cm3 for whole solar dried; 4.5±0.7-4.0±0.0 cm3 for sliced solar dried; 4.0±0.0 - 3.0±0.0 cm3 for whole cabinet dried and 3.5±0.7-2.3±0.7 cm3 for sliced cabinet dried leaf powder. Solar dried S. aethiopicum leaf powder contained significantly high moisture content than hot air cabinet dried one (24.9±0.5 % for saline treated sliced leaves to 8.9±0.8 % for blanched sliced leaves, than hot air cabinet dried one with 9.3±0.0 % for sliced plain water treated leaves to 7.0±0.2 % for sliced vinegar treated leaves; respectively). Cabinet dried S. aethiopicum contained significantly more vitamin C content (1.1±0.2 mg for whole blanched leaves compared to 0.6±0.1 mg for sliced vinegar treated leaves) than the solar dried one (1.0±0.2 mg for sliced plain water treated leaves to 0.6±0.1 mg for sliced vinegar treated leaves). There was no significant difference in phytate content between the hot air cabinet dried and solar dried i.e. 0.7±0.1 - 0.2±0.1 mg for solar and 0.7±0.1 - 0.3±0.3 mg for cabinet dried. Solar dried S. aethiopicum powder contained significantly higher catalase than the hot air cabinet dried one (4.5±0.7 - 3.0±0.0 and 4.0±0.0 - 2.5±0.7 cm3; respectively). However, in terms of acceptability, there was high preference for saline treated leaf powder soups compared to other soups. It can be concluded that High activity of catalase, moisture retention and high loss of Vit.C occurs in the solar drier than in cabinet drier. Whole leaf saline pretreated leaf powder soup is rated high compared to other dried soups. Therefore, the best method for production of dried S. aethiopicum powder is by slicing, dipping it in plain water and drying using a cabinet dryer. Under circumstances where cabinet drying is not achievable, solar drying is recommended using whole leaf, pretreated with saline water to promote preservation and consumption of the vegetable.
Effect of Different Rates of Poultry Manure and Bio-Slurry on the Yield of Solanum aethiopicum Shum
(Canadian Center of Science and Education 158, 2018-03) Nanyanzi, Mary; Kizito, Elizabeth B.; Masanza, Michael; Sseruwu, Godfrey; Makoma, Moses Tenywa
Poor soil fertility remains the major cause of low crop productivity on smallholder farms that are engaging in vegetable production in sub-Saharan Africa. Appropriate soil fertility regimes are therefore critical for improving crop productivity. Its yield has remained low mainly due to poor soil fertility. A field experiment in two different seasons was planted in a Completely Randomized Block Design using Solanum aethiopicum Shum (Nakati). The treatments were 3 sole fertilizer options applied at the following rates: poultry manure and bio-slurry manure at 5, 10, 15, 20, 25 and 30 t ha-1, NPK (25:5:5) at the recommend application rate for tomato which is a sister crop and a control without any fertilizer. Crop budgets were used to determine the economic optimum rates of both sole applications of manure and combinations of manure with NPK. The sole applications and showed significantly (p ≤ 0.05) increased the yield of S. aethiopicum compared with the control. The established biological optimum rates were at 24.19 t ha-1 and 21.51 t ha-1 for poultry manure and bio-slurry respectively. Using the crop budgets it was concluded that the established economic optimum rates were 20 t ha-1 and 10 t ha-1 for sole poultry manure and bio-slurry respectively. Recommendations for use of sole poultry manure and bioslurry at the rate of 20 t ha-1 and 10 t ha-1 respectively were made.
Effect of Post-Harvest Handling Practices, Storage Technologies and Packaging Material on Post-Harvest Quality and Antioxidant Potential of Solanum Aethiopicum (Shum) Leafy Vegetable
(Science and Education Publishing, 2018-05) Sekulya, S.; Nandutu, A.; Namutebi, A.; Ssozi, J.; Masanza, Michael; Jagwe, J. N.; Kasharu, A.; Rees, Deborah; Kizito, Elizabeth B.; Hedwig, Acham
Several studies have supported the use of vegetables as foods as well as medicinal plants. However, most especially for the leafy types of vegetables, their high moisture content gives them a short shelf life. On average Solanum aethiopicum (Shum) has a shelf life of one day, making it unable to keep fresh for a long time. The objective of this study was to determine the effect of post-harvest handling practices and storage technology on the post-harvest quality and antioxidant activity in S. aethiopicum, as well as determine the packaging material that could be able to maintain a high post-harvest quality during storage. The post-harvest handling and storage technologies were tested under three experimental conditions. Experiment one involved placing 2.0 kg of the harvested S. aethiopicum with roots intact (RI) and others with roots cut-off (RC) in a charcoal cooler (-CC), 21.0±1.00 °C, 95.67±3.01 %rh; in ambient storage (-AC), 23.8±2.86 °C, 69.38±6.72 % rh; and in cold room (-CR), 7.17±1.30 °C, 95.80±3.19 %rh. Experiment two involved storing 2.0 kg of S. aethiopicum in charcoal cooler with no water treatment (TT-) and in ambient storage while immersing in portable water for 2 to 3 seconds during the day (TT+). Experiment three involved packing 1.0 kg of S. aethiopicum sample of both RC and RI state to assess the effectiveness of the packaging materials (0.1 cm meshed perforated polyethylene (RC0.1), 0.5 cm meshed perforated polyethylene (RC0.5) and a 60 μm perforated polyethylene (RC60μm) in maintaining quality of the vegetables. The edible parts of the vegetable were tested for moisture content, percentage weight loss, chlorophyll content, polyphenol content and total antioxidant activity (as measures of post-harvest quality and shelf life) after every 24 hours. The antioxidant activity was determined by screening for free radical scavenging properties using diphenyl picryl hydrazyl (DPPH), Ferric reducing antioxidant power (FRAP) and ascorbic acid as standard. The results revealed that Shelf life was found to increase (from one day to four days) when the vegetable was intermittently immersed in portable water for 2 to 3 seconds after every one hour during the day for vegetables in ambient storage both with roots intact (RI(TT+)-AC and with roots cut-off RC(TT+)-AC). The samples stored in cold room and charcoal cooler showed slow and comparable reduction (percent) of weight for both intact and roots cut. The chlorophyll content decreased in all storage conditions, with ambient conditions showing the most rapid decrease. The total polyphenol fluctuated within relatively small limits for both with intact and roots cut-off when stored in cold room and charcoal cooler (6.25±0.05 to 9.35±0.05 mgGAE/gfw; respectively) within the four days of storage. Storage in ambient conditions indicated an increase in total polyphenol content from 9.35±0.05 to 14.77±0.12 mgGAE/gfw for that with roots intact (RI-AC) and to 13.65±0.06 mgGAE/gfw for roots cut-off (RC-AC). The increase in total polyphenol content in the ambient storage led to increased total antioxidant activity compared to that stored in cold room and charcoal cooler that remained almost constant. The 60 μm perforated polyethylene and 0.1 cm meshed perforated polyethylene retained more moisture (84.55±0.18 % and 85.20±0.03 %; respectively) and showed minimal percentage of weight loss (9.69±0.25 %) with the highest chlorophyll content (8.06±0.02 mg/g dwb) on day four when stored in the charcoal cooler, making it the best tested packaging material.
Effective Utilisation of Cassava Bio-Wastes Through Integrated Process Design: A Sustainable Approach to Indirect Waste Management
(Process Safety and Environmental Protection Journals, 2016) Tumwesigye, Kashub Steven; Morales-Oyervidesa, L; Oliveiraa, J.C.; Sousa-Gallagher, M.J.
An integrated process design, which can be applied in small-to-medium batch processing,was proposed. The process is based on the exploitation of intact (whole) cassavaroot, through optimisation of simultaneous release recovery cyanogenesis downstreamprocessing for sustainable wastes minimisation and packaging material development.An integrative seven unit process model flow was considered in the process design mod-elling. Using the release process models, it was possible to predict the maximum yield(45.8%) and the minimum total cyanogens (0.6 ppm) and colour difference (4.0) needed toavoid wastes and unsafe biopolymer derivatives. The process design allowed saving on theenergy and water due to its ability to reuse wastewaters in the reactions and release pro-cesses. Drying rates, Scanning electron micrograph, Differential scanning calorimetry, Watervapour transmission rate and Fourier transmission infrared spectroscopy analyses havedemonstrated the practical advantage of laminar flow hood air systems over oven-dryingheat for integrated process design.Thus, the integrated process design could be used as a green tool in production of cassavaproducts with near zero environmental waste disposal.
Effectiveness of Bylaws in Supporting Sustainable Crop Intensification: A Case of Potato Farming in Southwestern Uganda
(Journal of Agricultural Extension and Rural Development, 2021) Nampala, Paul; Kibwika, Paul; Makuma-Massa, Henry; Manyong, Victor; Yami, Mastewal
The study assessed the effectiveness of formal and informal bylaws in supporting sustainable crop intensification in potato farming regions of Southwestern Uganda. An exploratory case-study descriptive design was adopted, involving both qualitative and quantitative approaches. The study relied on data from the review of the existing formal and informal bylaws on sustainable crop intensification, key informant interviews, and focus group discussions. A total of 41 bylaws were assessed, involving key informants (22) and FDGs (6) respondents who participated in the study. The effectiveness of formal bylaws was high, because of the significant scores (7-8) on individual principles of effective institutions, with the highest principles being principle 2 (18%) and 7 (18%), and lowest being principle 8 (3%). The informal bylaws covered significantly only 2 principles of effective institutions from the total score 3 (100%). That is, principle 7 (37%) and 2 (33%), respectively. The coverage for 6 out of 8 principles was significantly very low. The study found greater levels of effectiveness significant for 7 out of 8 principles of effective institutions on formal bylaws more than informal bylaws (significant for principle 7 and 2 only), and most effective of the principles being principles 2 and 7 on both categories of bylaws. The study demonstrated the importance of both formal and informal bylaws in supporting SCI as both synergised each other in supporting intensification processes. The study recommends adapting existing bylaws to the eight designated principles of institutional effectiveness.
Engineered Food Supplement Excipients From Bitter Cassava for Minimisation of Cassava Processing Waste in Environment
(Future Foods Journal, 2020) Tumwesigye, Kashub Steven; O’Brien, E.; Oliveira, J.C.; Crean, A.; Sousa-Gallagher, Maria Jose
Unchecked large-scale rudimentary upstream (sub-merged and solid state) fermentation processes of bitter cas- sava roots into alcohol have often contributed significantly to agricultural wastes into environment. Thus, the study explored a proven valorisation methodology, Simultaneous Release Recovery Cyanogenesis (SRRC) along with intact bitter cassava polysaccharide-rich derivatives (CWF), as an apt to find alternative materials for food supplement excipients. Triplicate CWF powder, peeled or intact bitter cassava roots, were produced and analysed to determine crit- ical properties suitable in tablet making. Exclusion approach, using SRRC and compaction, was performed to select desired powder properties for tablet formulation. Microcrystalline cellulose, with known properties for developing drug excipients, was used as a validation reference material. Tablets, for disintegration time and in- vitro dissolution rates studies were produced using wet-granulation, and their potential to release and bio-avail Iron-Zinc investigated in-vitro (pHs 1.2 and 6.8 solutions, 37 0 C). Morphology and Iron-Zinc dissolution-release mechanisms were examined. Kinetic models were used to describe matrix dissolution and Iron-Zinc release mech- anisms. Intact root powder compaction capacity, depicted by hardness, was 4.3, 4.4 and 4.6 KG at 200, 500 and 700 MPa respectively. Scanning Electron Microscopy (SEM) showed Iron-Zinc inclusion altered tablet morphol- ogy. Efficient matrix dissolution and Iron and Zinc release were achieved, showing apex recovery efficiency (98%, 30–45 min). Fitted models well-explained dissolution and release mechanisms (mean R 2 = 0.95), demonstrating adequacy. SRRC-improved intact bitter cassava was confirmed as potential alternative excipient’s matrix for Iron and Zinc release and bioavailability. Thus, this approach is practical for indirect waste elimination, and can promote strategy for sustainable valorisation of agricultural wastes and alternative functional food supplements delivery system.

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