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Development of bio-pesticide for management of spodoptera frugiperda (j. e. smith) and other lepidoptera pests of maize in Tanzania
Get PDFA Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor
of Philosophy in Life Sciences of the Nelson Mandela African Institution of Science and
TechnologyThis study was conducted to evaluate the infestation levels and develop management option
for a Lepidoptera namely fall armyworm (Spodoptera frugiperda J. E. Smith). The survey
was carried out in three regions of northern Tanzania namely; Kilimanjaro, Arusha and
Manyara regions, and bioassay tests were conducted at the Hunan University of Technology
and Nelson Mandela African Institution of Science and Technology. Six villages per region
were surveyed, and a total of 210 maize growers were interviewed in all regions during maize
growing season in 2018. A scale of 0 (no damage) to 9 (100 % damage) was used to assess
severity of S. frugiperda in the study area. Performance of bio-based formulation against G.
mellonella and S. frugiperda were measure by the percentage of insect mortality recorded 2
days and 9 days post-treatment for entomopathogenic nematodes and plant extracts
treatments respectively. Data collected were analyzed using GenStat software 16
th
edition and
SPSS version 21. Results indicated that S. frugiperda incidence and severity level on maize
were 66.59 % and 5.422; 52.96 % and 4.756; 52.64 % and 3.989 for Arusha, Kilimanjaro and
Manyara regions respectively. The commonly applied pest management options by farmers in
the study area were synthetic pesticides (86 %) and non-synthetic methods (14 %).
Laboratory experiment showed that, formulations from Tephrosia vogelii and Dolichous
kilimandscharius caused S. frugiperda larvae mortality of up to 70 % and 60 % respectively.
Bio-based formulations from entomopathogenic nematodes (40 IJ/ml) caused G. mellonella
larvae mortality of up to 100 %. On the S. frugiperda, the same nematodes concentration
caused high mortality 48 h after treatment indicating that it can be used against S. frugiperda.
Bio-formulation of nematodes in UV protecting ingredients caused higher larvae mortality
(20 %) than the aqueous formulation (0 %) under direct sunlight for 6 h, indicating that
nanoparticles protected the nematodes against UV radiation. Of the two biopesticide
formulations, entomopathogenic nematodes had high performance, and thus, this study
recommends the use of entomopathogenic nematodes for the management of S. frugiperda
and other Lepidoptera. However, further study on their performance in different agricultural
systems is needed
Influence of Tobacco Plant on Macronutrient Levels in Sandy Soils
Get PDFThis research article was published by MDPI, 2020Tobacco (Nicotiana tabacum L.) is associated with great uptake of soil macronutrients.
Following the need to understand the macronutrients levels before and after tobacco cultivation,
research was conducted in loamy sand soil of Sikonge, Urambo, and sand soil of Tabora, Tanzania.
The initial macronutrients levels in the soil were compared with those measured after unfertilized
and fertilized tobacco. Results showed that unfertilized tobacco plant influences the increase of
nicotine to the rhizosphere, the macronutrients Ca (135%) > N (25%), decrease in the order of S (81%)
> P (49%) > Mg (12%) > K (11%). The sole e↵ect of nitrogen–phosphorus–potassium (NPK) and
calcium–ammonium–nitrate (CAN) 27% fertilizers increased further nicotine, Ca (25%) > N (20%) > S
(8%) > Mg (4%) > P (3%), and decreased K (3%) in the rhizosphere. Both tobacco plant and NPK +
CAN fertilizers on the rhizosphere increased Ca (193%) > N (50%) and decreased S (80%) > P (48%) >
K (14%) > Mg (8%). Leaf concentrations in fertilized tobacco increased Ca (197%) > K (28%) > P (27%)
> S (26%) > N (18%) > Mg (12%). Therefore, tobacco plant increases soil N and Ca but decreases P, K,
Mg, and S
Modelling the impact of climate change on Tanzanian forests
Get PDFThis research article was published by Wiley Online Library in 2020Aim: Climate change is pressing extra strain on the already degraded forest eco system in Tanzania. However, it is mostly unknown how climate change will affect
the distribution of forests in the future. We aimed to model the impacts of climate
change on natural forests to help inform national-level conservation and mitigation
strategies.
Location: Tanzania.
Methods: We conducted maximum entropy (MaxEnt) modelling to simulate forest
habitat suitability using the Tanzanian national forest inventory survey (1,307 oc currences) and environmental data. Changes in forest habitats were simulated under
two Representative Concentration Pathways (RCPs) emission scenarios RCP 4.5 and
RCP 8.5 for 2055 and 2085.
Results: The results indicate that climate change will threaten forest communities,
especially fragmented strips of montane forests. Even under optimistic emission
scenario, the extent of montane forest is projected to almost halve by 2085, inter secting many biodiversity hotspots across the Eastern Arc Mountains. Similarly, cli mate change is predicted to threaten microhabitat forests (i.e. thickets), with losses
exceeding 70% by 2085 (RCP8.5). Other forest habitats are predicted to decrease
(lowland forest and woodland) representing essential ecological networks, whereas
suitable habitats for carbon-rich mangroves are predicted to expand by more than
40% at both scenarios.
Conclusions: Climate change will impact forests by accelerating habitat loss, and
fragmentation and the remaining land suitable for forests will also be subject to pres sures associated with rising demand for food and biofuels. These changes are likely
to increase the probability of adverse impacts to the country's indigenous flora and
fauna. Our findings, therefore, call for a shift in conservation efforts, focusing on (i)
the enhanced management of existing protected areas that can absorb the impacts
of future climate change, and (ii) expanding conservation efforts into newly suitable
regions through effective land use planning and land reclamation, helping to preserve
and enhance forest connectivity between fragmented patches
Modeling the Impact of Seasonal Weather Variations on the Infectiology of Brucellosis
Get PDFThis research article published by Hindawi, 2020A deterministic mathematical model for brucellosis that incorporates seasonality on direct and indirect transmission parameters for domestic ruminants, wild animals, humans, and the environment was formulated and analyzed in this paper. Both analytical and numerical simulations are presented. From this study, the findings show that variations in seasonal weather have the great impact on the transmission dynamics of brucellosis in humans, livestock, and wild animals. Thus, in order for the disease to be controlled or eliminated, measures should be timely implemented upon the fluctuation in the transmission of the disease
The in vivo toxicity evaluation of leaf and root methanolic extracts of Tephrosia vogelii Hook.f using animal model
Get PDFThis research article published by Springer Nature, 2020Background: Traditionally, herbal medicines are commonly used to cure several diseases since immemorial of
human life. Nevertheless, the safety of some traditionally used medicinal plants is uncertain. Since Tephrosia vogelii
Hook.f is a traditionally used medicinal plant, the effects of its extracts were evaluated on lethality (LD50) and subacute toxicity in this study.
Methods: Phytochemistry screening and an in vivo toxicity evaluation of leaf and root methanolic extracts of T.
vogelii using laboratory albino rats were conducted. Methanolic extracts of doses 600, 1200, 2000 and 5000 mg/kg
body weights were administered single dose in rats to observe deaths within 72 h in order to determine the LD50.
Methanolic extracts doses of 600, 1200 and 2000 mg/kg body weights were consecutively administered for 14 days
in order to evaluate sub-acute toxicity.
Results: Tannins, steroids, terpenoids, flavonoids and saponins were identified in the phytochemical screening. The
LD50 experiments revealed zero deaths of rats for the administered doses, 600 to 5000 mg/kg body weight.
Histopathological examination of liver and kidney for sub-acute toxicity test showed safety at all doses except root
methanolic extracts dose of 2000 mg/kg which exhibited necrosis and vacuolation of liver cells on the 14th day.
Nonetheless, hepatic necrosis and hepatic vacuolation disappeared upon time elongation without dose
administration to 28th day.
Conclusion: The conducted toxicity evaluation of methanolic leaf and root extracts in albino rats revealed no
deleterious effects, henceforth, suggesting that T. vogelii could be safe to users using it as a medicinal plant
Plant Growth Promoting Rhizobacterial Biofertilizers for Sustainable Crop Production: The Past, Present, and Future
Get PDFThis research article was published by Preprints in 2020The world’s population is increasing and so are agricultural activities to match the growing demand for food. Conventional agricultural practices generally employ artificial fertilizers to increase crop yields, but these have multiple environmental and human health effects. For decades, environmentalists and sustainability researchers have focused on alternative crop fertilization mechanisms to address these challenges, and biofertilizers have constantly been researched, recommended, and even successfully-adopted for several crops. Biofertilizers are microbial formulations made of indigenous plant growth-promoting rhizobacteria (PGPR) which can naturally improve plant growth either directly or indirectly, through the production of phytohormones, solubilization of soil nutrients, and production of iron-binding metabolites; siderophores. Biofertilizers, therefore, hold immense potential as tools for sustainable crop production especially in the wake of climate change and global warming. Despite the mounting interest in this technology, their full potential has not yet been realized. This review updates our understanding of the PGPR biofertilizers and sustainable crop production. It evaluates the history of these microbial products, assesses their present state of utilization, and also critically propounds on their future prospects for sustainable crop production. Such information is desirable to fully evaluate their potential and can ultimately pave the way for their increased adoption for crop production
The Role of a Web Portal to Facilitate Higher Learning Institutions Students’ Field Attachment in Tanzania
Get PDFA research article was submitted to Journal of Information Systems Engineering and Management 2020, volume 5One of the approaches applied by Higher Learning Institutions to equip students with the practical skills is through
field attachment in relevant companies based on field of studies. There are so many challenges in the process of
coordination and allocation of students to relevant companies including expenses in terms of time and resources
due to prolonged process involved. A web-based portal was developed to address the challenges for Tanzanian
context. The development approach based on Scrum framework was employed to allow users involvement. To
ensure information completeness, mixed-methods approach including key informant interviews, observations
and requirements workshop were applied for portal’s requirements elicitation. The requirements determined
from users were further used to guide initial interface designs which were then converted to clickable wireframe
pages using pencil software. The prototype was sent to real users via email for testing and improvement
suggestions before real portal development. Scrum development approach was employed where increments
development progress were frequently inspected to detect undesirable variances. The portal was finally validated
and tested for usability and indicated to have improved field attachment process and open doors for more
collaboration between Higher Learning Institutions and companies. This study provides insight on the approach
used to come up with the solution regarding current challenges. Moreover, the contribution that the research
based solution has brought to the students’ field practices process is identified
Prevalence of hypertension and its association to HIV related factors among HIV patients on antiretroviral medications in Bagamoyo district, Tanzania
Get PDFA Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree in
Master of Science in Public Health Research at Nelson Mandela African Institution of
Science and TechnologyEffective use of antiretroviral therapy (ART), has greatly upgraded the quality of life and
survival of individuals suffering from HIV/AIDS. However, the incidence rate of
hypertension is reported growing up. The overall aim was to find out the prevalence of
hypertension and its association with HIV related factors in HIV patients on ART, in
Bagamoyo district Tanzania. The design was a cross-sectional study of HIV patients on ART
visiting care and treatment clinics. Hypertension was defined as systolic blood pressure ≥ 140
mmHg, diastolic blood pressure ≥ 90 mmHg or being on medications for hypertension.
Logistic regression was applied during the analysis. The study investigated 328 HIV patients
on ART, 64.6% were female, and 92.68% on non-protease inhibitors medication and 14%
had a prior history of TB in the past 5 years. The overall prevalence of hypertension was
29.3% and it was significantly and positively associated with increasing age (years): 40-59,
3.40 (1.80-6.41) 0.001, ≥ 60, 9.25 (3.96-21.60) 0.001, obesity 3.63 (1.60-8.26) 0.002, nonprotease
inhibitors
4.31
(1.16-16.03)
0.029
and
tenofovir
4.27
(1.15-15.96)
0.031.
Both
of
the
duration
since HIV diagnosed, recent CD4+cell count and history of TB in the past 5 years
were not statistically significant associated with increased odds of having hypertension. In
conclusion the prevalence of hypertension in HIV patients on ART was 29.3% and it was
significantly and positively associated with increasing age, obesity, and non-protease
inhibitors. Regular monitoring of blood pressure, anthropometrics, and ART drug toxicity are
crucial among HIV patients
Removal of Hydrogen Sulfide from Biogas Using a Red Rock
No full textThis research article published by Hindawi, 2020The potential of red rock (RR) materials for the removal of H2S from biogas was studied. The rock samples were collected, sieved, and organized in various particle size ranges such as 0.32-250 μm, 250-500 μm, 500-750 μm, 750 μm-1 mm, and 1-1.5 mm. These samples were calcinated at the various temperatures as 500°C, 750°C, and 1000°C and then characterized for phase composition by energy-dispersive X-ray florescent technique, surface morphology by Zeiss Ultra Plus Field Emission Scanning Electron Microscopy (FE-SEM), and surface area by the Brunauer-Emmett-Teller (BET) method. The calcinated RR was filled in the bed reactor, and biogas was allowed to pass through the adsorbent while recording the inlet and exit concentration of H2S. The results show that particle size, calcination temperature, adsorbent mass, and biogas flow rate were parameters that influenced the removal efficiency and adsorption capacity of RR. The sample sieved at 0.32-250 μm and calcinated at a temperature of 1000°C showed 95% high removal efficiency and adsorption capacity of 0.37 g/100 g of the sorbent. Regeneration of spent materials when exposed to air, keep on by reuse in the column, appeared to have nearly similar removal efficiency as the original calcined sample. Thus, the overall performance of the material is promising, which is due to the presence of metals such as iron and magnesium, among others. Therefore, proving the successful elimination of contaminant, RR is an available material for biogas purification
A Survey of Monitoring and Evaluation Systems for Government Projects in Tanzania: A Case of Health Projects
Get PDFThis research article published by Modern Education and Computer Science Press, 2020Monitoring and Evaluation (M&E) system are used across the world by organizations or governments to track progress, measure and evaluate outcomes of projects. Organizations can improve their performance, effectiveness and achieving results in project success by strengthening their monitoring and evaluation systems. Moreover, various studies reveal the need for information and communication technology systems in monitoring and evaluation activities because most of the government organizations do not employ computerized monitoring and evaluation systems and those having these systems lack a systematic early informing mechanism of the projects' progress. Currently, the Ministry of Health in Tanzania monitors and evaluates its projects manually, due to this, they face the risks and challenges during the implementation of projects because of a lack of having timely adoption of remedial action. Monitoring and evaluation staffs spent a lot of time in manual work, manual compilation of data, due to data being in separate systems, delay in submission of data, data is lost between primary registries to monthly summaries, from monthly to quarterly summaries, system does not contain all details about projects/program as well as budget information, no early alert information about the status of the project, poor information sharing among stakeholder.
In this study, we collect representative data from three monitoring and evaluation staff, four ICT staff and five project members by using interviews, focus group discussion and document review. The result showed that the electronic monitoring and evaluation system will solve a presented challenge. Development of a web-based monitoring and evaluation system for the ministry of health projects will provides timely, accurate information, that for tracking the implementation progress of projects improved monitoring and evaluation