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Theses and Dissertations: Recent submissions
Now showing items 21-40 of 80
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Assessing the potential of the ECMWF-S5 satellite-based seasonal rainfall forecasts for improved crop farming in Ghana
(Kwame Nkrumah University of Science and Technology, 2022-09)Forecasts of seasonal rainfall are important for the agricultural sector, particularly in nations where rain-fed agriculture is predominant. A robust agricultural system is made possible by the ability to predict seasonal rainfall with accuracy and precision. Due to the limited and sparse availability of gauge data, both satellite-based and model seasonal rainfall forecasts are beneficial for predicting seasonal rainfall. While seasonal rainfall forecasts based on models and satellites complement ... -
Bias correction of daily chirps-V2 rainfall estimates in Ghana
(Kwame Nkrumah University of Science and Technology, 2022-10)A wide range of economic sectors in the Ghana, including agriculture, health care, and energy, heavily rely on climate data; as a result, having access to reliable climate data is crucial for research and economic growth yet rainfall gauge data in Ghana scarcely available, therefore, researchers tend to depend on satellite estimates for hydrological studies and impact assessments. However, biases in satellite rainfall estimates and the ability for these rainfall products to effectively capture ... -
Impact and adoption of drought tolerant maize varieties and interrelated agricultural technologies on rural households productivity and welfare
(University of Greeenwich, 2021)Over the years, climatic variations have persistently induced technological interventions in developing countries and were strategic in varietal development and modification of agronomical practices in developing countries. In addition, there are overwhelming records of impact on productivity and welfare of rural farm households. Despite these efforts, low adoption continues to be a huge problem and a clog to meeting sustainable agricultural development goals. This research contributes to the large ... -
Adoption et perception des producteurs Nigeriens face aux changements climatiques et l'utilisation des varietes ameliorees
(Institut de Strategie D'evaluation et de Prospective, 2021)L’agriculture Nigérienne fait face à une faible production agricole car étant une agriculture pluviale à faible rendement, et l’élevage, un élevage extensif tributaire des ressources naturelles. IL est de plus en plus admis que le réchauffement planétaire actuel ne peut être évité (IPCC, 2007). Le recours à l’adoption des technologies agricoles améliorées s’est avéré indispensable pour une augmentation de la production agricole dans le but d’améliorer le bien-être des producteurs. Ainsi, dans notre ... -
Development of a multi-layer gene regulatory network perturbation simulation model for host-pathogen interaction studies
(University of Ibadan, 2021-12)Gene Regulatory Networks (GRNs) modulate the traits of an organism. Perturbation experiments which were employed to identify Trait-influencing Genes (TGs) are limited to only a few genes at once, and inadequate to identify the TGs of complex traits like disease resistance. Network modelling techniques for complex systems such as GRNs can provide a holistic system view to overcome the limitation of identifying TGs of complex traits with perturbation experiments when applied to genome-wide Next ... -
Genome-wide association mapping and stability analysis of root mealiness in cassava (Manihot esculenta Crantz)
(University of Ghana, 2020-12)Cassava breeders have made significant progress in developing new genotypes with improved agronomic characteristics such as improved root yield. However, these new and improved cassava genotypes in cultivation in Nigeria have undergone little or no improvement in their culinary qualities; hence, there is a paucity of information on the texture of boiled cassava roots, particularly with regard to its mealiness. The objectives of this study were to: (i) elicit farmers’ knowledge, perceptions and ... -
Effects of agroforestry and climate on cocoa yield, pests and diseases
(University of Ghana, 2021-06)Cocoa (Theobroma cacao) originates from the Amazon basin in South America. The crop is cultivated across many tropical regions, with the largest production from West Africa, where Ghana and Cote d’Ivoire contribute 70% of global production. Two major systems dominate cocoa production; a full-sun monocropping system where the cocoa crop is grown without shade trees, and an agroforestry system where cocoa is grown with deliberately planted or retained forest/fruit trees. Aside soil fertility and ... -
Rapid detection of adulterated fermented maize (Ogi) with sorghum leaf sheath (Poroporo) using visible-near infrared spectroscopy
(University of Ibadan, 2022-03)Food adulteration is a very old and common problem, which is often seen in both the low-and middle-income countries and even in some developed countries. Maize-based porridge especially ogi is a high-value commodity and common indigenous complementary food that is a target for adulteration, leading to loss of quality and encroachment on the rights and interests of consumers. This study investigated the characterization of the microorganisms found in ogi fermented for 0 to 120 hours and the feasibility ... -
Inheritance patterns and genome-wide association study of tropical early-maturing maize inbred lines under striga infestation and drought stress environments
(Obafemi Awolowo University, 2021)This study determined the gene action controlling grain yield and other agronomic traits among newly-developed early-maturing maize inbred lines under drought stress, Striga infestation, optimal conditions and across research environments; examined the combining ability of the early maize inbred lines under each and across research environments; classified the inbred lines into heterotic groups using DArTseq (Diversity Arrays Technology sequencing) markers and combining ability effects methods and ... -
Title Open Data Kit (ODK) in crop farming: an introduction of mobile data collection methods in seed yam tracking in Ibadan, Nigeria
(2020)The purpose of this paper is to illustrate the importance of applying open-source technologies for mobile-based data collection for real-time tracking of seed yam (Dioscorea rotundata and Dioscorea alata) production. Seed yam data in Nigeria have been predominantly collected using field notebooks in the past, which were subsequently entered into a Microsoft Excel spreadsheet or Access database for analysis and reposition. Relevant areas of weakness within the current data systems include time delay ... -
The quality of Cocoa Pod Husk Biochar produced with the "Kon-tiki" kiln technology, and its effect as a soil enhancer on the growth rate of cocoa seedlings
(Norwagien University of Life Sciences, 2021)A study was conducted to investigate the potential of cocoa pod husk as feedstock for biochar production using the “Kon-tiki” kiln. The effect of cocoa pod husk biochar (CPHB) as a soil enhancer, was tested in particular with respect to the soil’s capacity to retain moisture and nutrients, and their consequences for the growth rate of cocoa seedling on two soil types. The resultant CPHB biochar was applied on two soil types from Ghana, Acherensua (sandy loam and near neutral) soil and Ayinase ... -
Assessment of some high ratio propagation technologies for quality seed yam tuber production in Dioscorea alata L. and Dioscorea rotundata Poir
(University of Ibadan, 2021-10)Edible yams are widely cultivated staple food crops in the tropics, but their production is constrained by low multiplication ratio, which results in short supply of Seed Yam Tubers (SYT). The use of High-ratio Propagation Technologies (HrPT) could enhance quality and quantity of SYT. However, limited information is available on the use of HrPT and the amenability of yam varieties to HrPT for SYT production. In this study, the uses of some HrPT for quality SYT production in Dioscorea alata and ... -
Morphological characterization of cacao cultivars in different socio-ecological settings of Ghana
(Georg-August-Universitat Gottingen, 2022-07-15)Knowledge of Theobroma cacao morphological variability provides the foundation for the utilization and conservation of genetic resources in Ghana. This study concentrated on cacao varieties, varietal richness and diversity maintained on farmers` fields. The objectives of the study were (1) to assess varietal richness per farm and the level of homozygosity of cacao cultivars on farmers’ fields through morphological analysis and farm management. (2) To identify existing cacao cultivars in the ... -
Genetic diversity in cowpea [Vigna unguiculata (L.) Walp.] accessions collected from Togo
(Pan African University, 2021-11)Cowpea is one of the most widely grown legumes in Togo for its grains and leaves, which are used both as food and feed. Despite its importance in the nutrition and economic life of the people, bulk of the varieties grown in Togo are landraces. Genetic improvement of crops requires the presence of heritable genetic variation. However, there is hardly any information on the extent of variability among cultivated cowpea in Togo. This study was carried out to assess the phenotypic and molecular diversity ... -
Smallholder farmers' constraints to maize growth and yield variability in the northern guinea savannah of Nigeria
(Bayero University Kano, 2021)Maize yield has been on the decline on smallholder farms, where the bulk of maize for different uses is produced in the Northern Guinea Savannah of Nigeria. This study analyzed smallholder farmers‘ constraints to maize growth and yield variability in the Northern Guinea Savannah (NGS) of Nigeria for yield optimization. It temporally covers 2017 and 2018 at 4 Weeks After Sowing (WAS) and 8WAS. For Ikara in Kaduna State and Doguwa in Kano State, 30 and 31 farmers respectively were purposively selected ... -
Comparison of metabolite profile of aflatoxin-contaminated yellow and white maize Ogi after fermentation with lactic acid bacteria and yeast
(University of Ibadan, 2021-01)Aflatoxins are a group of highly toxic, mutagenic, teratogenic, and carcinogenic secondary metabolites of Aspergillus species including Aspergillus flavus and Aspergillus parasiticus. Maize is susceptible to aflatoxin contamination; so, ogi, (fermented maize gruel) consumed as a breakfast cereal, weaning food and food for convalescents is prone to aflatoxins. Therefore, targeted fermentation of yellow and white maize, for ogi, was investigated as a means of aflatoxin decontamination in ogi. Methods ... -
Cassava production improvement through staggered planting for industrial processing and utilization in eastern and southern zones of Tanzania
(Sokoine University of Agriculture, 2019)An experiment was conducted with the aim of identifying suitable cassava scheduled planting, harvesting and varietal performance in order to optimize growth, development, yield and quality of cassava during the 2017/18 - 2018/19 cropping season. The experiment was conducted at Naliendele, Nachingwea and Ilonga TARI Research Centres in Tanzania. The experiment was laid out as split-split plot in a randomized complete block design with variety being main factor, harvesting time as sub plot and ... -
Evaluation of starches digestibility and glycemic index of commonly consumed sstaple foods from selected varieties of cassava (Manihot sp.) and yam (Dioscorea sp.)
(University of Ibadan, 2019-08)Consumption of high Glycemic Index (GI) foods is a risk factor for increasing prevalence of metabolic related non-communicable diseases. Cassava and yam are among common staples known to have high GI and are usually avoided by diabetics because they can rapidly raise blood glucose. Currently, it is still unclear if common varieties (and their corresponding products) have different starch digestibility and GI. This study was therefore designed to evaluate starch digestibility and GI of common foods ... -
Unravelling the diversity and distribution of the soybean rust fungus Phakopsora pachyrhizi in east Africa
(Wageningen University and Research, 2019-02)Soybean is an important legume crop that is cultivated worldwide on more than 120 million hectares, producing more than 330 million tonnes of soybeans annually. Soybeans contain 40% of protein and 20% of oil and the crop is therefore used both for human and livestock consumption. Generally, soybean has the potential to significantly improve the nutrition of the inhabitants of sub-Saharan Africa. Soybean production has intensified in Africa over the past 15 years, owing to the raising demand driven ... -
Cassava farmers' insights and seed dealers enterprises in Nigeria
(University of Ibadan, 2019)Seed enterprise is an initiative and risk set up in the production of cassava stems from existing local seed varieties or improved seed varieties for economically sustainable profit. Although, most cassava seeds produced are through informal seed system among smallholder farmers but there is need for replacement strategy for cassava seeds mostly planted over years. Based on this, there is need for intense exploration in the linkage between cassava seed management and diffusion scheme among rural ...