UCUDIRBrowsing by Author "Masanza, Michael"

Browsing by Author "Masanza, Michael"

Now showing 1 - 15 of 15

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
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.
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.
Dentification of Growth Stage-Specific Watering Thresholds for Drought Screening in Solanum aethiopicum Shum
(Natureresearch, 2020) Nakanwagi, Mildred Julian; Sseremba, Godfrey; Kabod Nahamya , Pamela; Masanza, Michael; Balyejusa Kizito, Elizabeth
Effective phenotyping for drought resistance is a pre-requisite for identification of modest crop varieties for farmers. For neglected and underutilized crops such as Solanum aethiopicum Shum group, no drought screening protocol based on rigorous iterations has been documented. A split-plot nested treatment structure was arranged in an experiment to identify growth stage-specific watering thresholds for this crop. Three plant growth stages (main plot; seedling, vegetative and flowering), watering regime at plant growth stage (2 regimes; well-watered and drought stressed) and day since last watering at plant growth stage were evaluated for soil moisture content (SMC), leaf wilting score (LWS), number of green leaves per plant (LPP) and leaf blade width (LBW). Highly significant differences (p < 0.001) were found at the different plant growth stages, watering regime (WR) within plant growth stage, and day within WR and plant growth stage. Under drought stress treatment, SMC declined exponentially at each stage. The earliest leaf wilting, reduction in LPP and LBW were generally observed at flowering followed by vegetative and slowest at the seedling stage. For future effective drought phenotyping studies in S. aethiopicum Shum and related crops, we recommend setting minimum drought stress treatments below 18% SMC at which the LWS is ≥2 at the vegetative.
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
Effect of crop sanitation on banana weevil Cosmopolites sordidus (Germar) populations and associated damage
(Wageningen University and Research Centre, the Netherlands, 2003) Masanza, Michael
The banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) is a serious pest of bananas. However, its ecology is not well elucidated especially in East Africa where plantations are up to 50 years old and are under various management and cropping systems. No single satisfactory control strategy has been found. Detailed information on C. sordidus biology and ecology is needed to explain the population dynamics of this pest in order to develop a comprehensive package for the small-scale farmer to alleviate the pest problem. Cultural control forms the first line of defence in pest control. For instance, removal of crop residues after harvest by chopping is a widely recommended cultural strategy for C. sordidus control. However, the actual effect of these practices on the insect's population dynamics is not clear. This study was aimed at investigating the effect of crop sanitation on population dynamics of C. sordidus and its associated damage. Laboratory and field studies on the biology and ecology of this pest on crop residues were conducted in Uganda. We found that corms are most attractive to the weevils than any other type of crop residues. Oviposition occurred on residues up to 120 days after harvest, but mainly on freshly harvested residues up to 30 days, implying that residues should be left up to a month before destroying them. In the study on survivorship of C. sordidus in crop residues, our results revealed that the pest successfully completes its life cycle within crop residues and emerging adults from different aged residues are equally fit. As crop residues can be a source of C. sordidus infestation to the standing crop, they need to be destroyed. There is a general belief that covering banana stumps after harvest helps reduce weevils in banana farms. However, there was no data available to prove that this practice is useful. Moreover, the real effect of covering stumps remained unknown. Our studies reveal that covering banana stumps after harvest reduces oviposition on them in the wet season, but encourages oviposition in the dry season. Therefore, farmers may cover the stumps in the wet but not in the dry season. Also, our studies suggest that covering all stumps in the wet season may encourage C. sordidus to oviposit on the crop. Therefore, some residues should be left in the inter-mat alleys to attract weevils away from the crop. The residues can then be destroyed after three to four weeks. Removal and chopping crop residues in farmers' fields helped to keep C. sordidus populations and damage lower than when the residues were left to accumulate. In comparison, removal of all residues in young closed banana plots reduced C. sordidus populations but increased damage on growing plants and reduced the levels of natural enemies. The implications of these results on the role of crop sanitation in the integrated management of C. sordidus are discussed.
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.
Identification of Growth Stage Specific Watering Thresholds for Drought Screening in Solanum aethiopicum Shum
(Nature Research, 2020-01-21) Nakanwagi, Mildred Julian; Sseremba, Godfrey; Nahamya, Pamela Kabod; Masanza, Michael; Kizito, Elizabeth Balyejusa
Effective phenotyping for drought resistance is a pre-requisite for identification of modest crop varieties for farmers. For neglected and underutilized crops such as Solanum aethiopicum Shum group, no drought screening protocol based on rigorous iterations has been documented. A split-plot nested treatment structure was arranged in an experiment to identify growth stage-specific watering thresholds for this crop. Three plant growth stages (main plot; seedling, vegetative and flowering), watering regime at plant growth stage (2 regimes; well-watered and drought stressed) and day since last watering at plant growth stage were evaluated for soil moisture content (SMC), leaf wilting score (LWS), number of green leaves per plant (LPP) and leaf blade width (LBW). Highly significant differences (p < 0.001) were found at the different plant growth stages, watering regime (WR) within plant growth stage, and day within WR and plant growth stage. Under drought stress treatment, SMC declined exponentially at each stage. The earliest leaf wilting, reduction in LPP and LBW were generally observed at flowering followed by vegetative and slowest at the seedling stage. For future effective drought phenotyping studies in S. aethiopicum Shum and related crops, we recommend setting minimum drought stress treatments below 18% SMC at which the LWS is ≥2 at the vegetative
Influence of Plant and Residue Age on Attraction, Acceptance and Larval Survival of the Banana Weevil Cosmopolites sordidus (Coleoptera: Curculionidae)
(International Journal of Tropical Insect Science, 2009) Masanza, Michael; Gold, C.S.; Huis, A. van
Laboratory trials were conducted in Uganda at the Kawanda Agricultural Research Institute to determine attraction, eclosion success and larval survivorship of the banana weevil Cosmopolites sordidus (Germar) on crop residues of different ages. In the first experiment, studies focused on different types and ages of residues of one susceptible highland banana clone ‘Nabusa’ (genome group AAA-EA). Corms attracted 65% of the test weevils, pseudostems 30%, while 5% were non-respondents. Oviposition levels and the number of eggs per female were higher on young than old corms. Eclosion rates of ,1-day-old eggs inserted into corm pieces of residues (cultivar ‘Kisansa’, genome group AAA-EA) declined from 66% in residues collected ,2 days after harvest (DAH) to 58% in residues collected .30 DAH. To assess immature survival, ,1-day-old 1st instar larvae were put on banana corms of suckers and crop residues of the cultivar Kisansa in single rearing chambers. The number of surviving individuals was recorded at 3-day intervals until adults emerged. Survivorship was 12% on sword suckers, 10% on maiden suckers and 7% on flowered plants; and 12% on residues collected ,2 DAH and 5% on residues collected .30 DAH. Larval duration and mean days taken for adult emergence increased with plant and crop residue age. Females emerging from the different plant and residues treatments were similar in weight. The data suggest that all aged residues are suitable hosts for C. sordidus, suggesting that sanitation practices should be implemented soon after harvest.
Performance of Solanum aethiopicum Shum group accessions under repetitive drought stress.
(2018-01) Nakanwagi, Mildred Julian; Sseremba, Godfrey; Masanza, Michael; Kizito, Elizabeth B.
Drought is a serious climatic hazard to crop production, more especially when it occurs repeatedly. This created a need to identify repetitive drought tolerant varieties that recover following exposure to drought. Twenty accessions of Solanum aethiopicum Shum group were evaluated for their response to repeated drought exposure in a screen house at Uganda Christian University stressed and well-watered conditions in a split-plot arrangement. Data was collected on growth and yield parameters namely leaf area, plant canopy width, plant height, plant branching, fresh leaf weight, fresh shoot biomass, and harvest index. Exposure of plants to repetitive drought stress led to significant decrease in all evaluated growth parameters at p<0.001 except for plant branching. Similarly, yield parameters exhibited a highly significant difference among accessions and between water levels at p<0.001. Principal component analysis of growth rate traits showed that leaf area contributed to the highest variation for recovery from repetitive drought stress among accessions. The accessions that recovered best from drought stress include SAS108/2015, SAS163/P/2015, SAS183/G/2015, and SAS168/G/2015. For yield parameters, the accessions SAS137/2015, SAS148/2015, SAS108/P/2015, and SAS160/2015 had the highest dry shoot biomass. These findings indicate prospect for improvement of tolerance to repetitive drought stress in S. aethiopicum Shum group.
Stability for Descriptors of Solanum aethiopicum Shum Group (Family Solanaceae)
(Journal of Plant Breeding and Crop Science, 2018-09-30) Kabod, Nahamya Pamela; Sseremba, Godfrey; Buteme, Ruth; Masanza, Michael; Kizito, Balyejusa Elizabeth; Kasharu, Katwijukye Apolo
Solanum aethiopicum Shum group is a nutrient-rich and income-generating crop enterprise in various sub-Saharan Africa countries. Despite its importance, the development of its improved varieties has not been prioritized. Until now, no field-based descriptor development reference for the crop is available for testing candidate varieties for distinctiveness, uniformity and stability. The purpose of this study is to identify morphological variables that provide identity of S. aethiopicum Shum group accessions across environments. With ten accessions across three test locations, it was observed that the highly polymorphic morphological variables were majorly vegetative and a few reproductive ones. They include plant height at flowering, plant canopy breadth, plant branching, petiole color, petiole length, leaf blade length, leaf blade width, leaf lobbing, leaf tip angle, flowering time, style length, fruit position, fruit flesh density, fruits per inflorescence and fruit flavor. A static stability analysis, a common selection technique for obtaining consistence in performance of genotypes, showed that accessions varied in their interaction with environments for different descriptors. The most statically stable accessions were 184P and 163P while the least stables were 168P, 148, 141, and 137. The findings indicate the potential for identifying unique and stable varieties of S. aethiopicum Shum group for the processing of official release to farmers.
Stalk-eyed fly, Diopsis sp. population dynamics under varying temperature and Relative Humidity in rice ecosystems
(2018-02) Kayongo, Charles; Mbogga, Michael S.; Goncalves, de Abreu Aluana; Masika, Fred; Masanza, Michael; Barrigossi, Jose Alexandre Freitas; Kizito, Elizabeth B.
Although the stalk-eyed fly (Diopsis sp.) has been observed in Ugandan rice fields, there is limited information on the fly’s population and its potential threat to rice production. This study assessed the stalk-eyed fly (Diopsis longicornis and Diopsis apicalis) population dynamics under varying temperature and relative humidity in rice ecosystems of Uganda. It was conducted in purposively selected small scale rice farming sub-counties in low land rain fed and irrigated rice agro-ecologies (Lake Victoria Crescent, Kasese transition zone and Northern moist farmlands). Diopsis sp. populations were monitored by sampling rice fields every 40 days for a period of 17 months. Weather parameters including air temperature and humidity were recorded by use of data loggers throughout the study period. R-statistical tool and MS Excel were used to assess the population dynamics and interactions of the diopsids. D. longicornis fly was dominantly abundant in rice fields of Lake Victoria Crescent and Northern Moist zones while D. apicalis was dominant in Kasese transition zone. There was significant mean count variations per survey for both species in all the agro-ecological zones with P-values of 0.000958 (D. longicornis) and 1.12e-12 (D. apicalis) in Lake Victoria crescent, 0.000473 (D. apicalis) and 0.0173 (D. longicornis) in Northern moist farmlands, 0.0188 (D. apicalis) and 0.0353 (D. longicornis) in Kasese transition zone. Temperature and relative humidity had a direct effect on the population of both species in Northern moist zone and only on D. apicalis in Kasese transition zone. The optimum/favorable temperatures for abundance were between 27oC and 29oC. Interpretation of the results? Integrated pest management strategies and introduction of improved Diopsis pest resistant rice varieties are some of the recommendations for managing the stalk-eyed fly populations in these rice ecosystems.

Browsing by Author "Masanza, Michael"

Results Per Page

Sort Options