Now showing items 81-100 of 111

    • Interactions between the germplasm of okra (Abelmoschus spp.) and Aphids with special reference to Aphis gossypii Glover (Hemiptera: Aphididae) in Cameroon 

      Abang, A.F. (University of Yaounde I, 2018)
      Aphis gossypii Glover (Hemiptera: Aphididae) is one of the major pests of okra (Abelmoschus spp). On one hand, direct damages due to its feeding habit results in curling and deformation of young leaves. On the other hand, indirect damages are caused because of honeydew secreted on fruits and leaves with, which in turn may promot growth of black sooty mould. The black sooty mouls stain and reduce fruit and leaf quality and reduce photosynthetic activity. In addition, honeydew attracts ants that ...
    • Soybean (Glycine max) response to rhizobia inoculation as influenced by soil nitrogen levels 

      Nyaguthii, M.C. (Suba, Kenya, 2017-05)
      Inoculation of soybean (Glycine max) is an efficient and convenient way of introducing rhizobia to soil and subsequently the rhizosphere of the crop. However, its full potential in sub-Saharan Africa is yet to be realized due to effects of varying soil limiting conditions. Critical levels of nitrogen (N) below and above which response is not guaranteed are unknown. The objective of the study was to determine the critical range of N outside which response to inoculation is hindered. Below the lower ...
    • The economic impact of climate change on farm decisions and food consumption in Ghana 

      Etwire, P.M. (University of Otago, 2018-05)
      Climate change poses a serious threat to the growth of developing countries, especially Ghana where the majority of people derive their livelihoods directly from agriculture and related industries. This thesis sets out to examine the economic impact of climate change on agriculture by modelling climate, household, and farm data from Ghana. The impact is assessed through three connected empirical studies. In our first empirical study, we estimate a multinomial logit (8,700 observations) in order ...
    • Genetic diversity in cowpea [Vigna unguiculata (L.) Walp.] accessions collected from Togo 

      Gbedevi, K.M. (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 ...
    • Genetic diversity in cowpea [Vigna unguiculata (L.) Walp.] accessions collected from Togo 

      Gbadevi, K.M. (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 ...
    • Genetic diversity of Striga hermonthica (Del.) benth. weeds from Nigeria and Kenya, and the genetic responses of selected hist maize lines 

      Unachukwu, N. (University of Ibadan, 2019-12)
      Striga hermonthica (SH) is a parasitic weed that attacks and significantly reduces the yield of maize in Africa. The genetic interactions responsible for resistance or susceptibility of hosts to the parasite and the genetic differentiation that exists between and within SH populations are not fully known. This study investigated the genetic diversity of SH populations in the largest maize producers in Sub-Saharan Africa (Kenya and Nigeria) and; the genetic responses of a susceptible (5057) and a ...
    • Response of promiscuous soybean to rhizobial inoculation in combination with organic and mineral fertilizers in some soils of the Nigeria Guinea Savanna 

      Ekaette, J.E. (Federal University of Technology, Minna, 2017)
      Effective soybean rhizobia are seldom found in sufficient or large numbers in the soils that have no history of soybean cultivation. There may be a need for soybean grown in such soils to be supplied with inoculant rhizobia to ensure optimal inputs from biological nitrogen fixation. Reports have indicated that yield per hectare of soybean in farmers’ fields are still very low. This scenario calls for trials that are capable of establishing some of the biophysical factors limiting the yield of ...
    • Genetic improvement of cowpea for resistance to thrips (Megalurthrips sjostedti) in Mali 

      Doumbia, I. (University of Ghana, 2016)
      Several techniques, such as chemical and bio-insecticides have been applied by farmers to control thrips (Megalurothrips sjostedti) damage on cowpea. Many factors, such as improper amount of insecticides to dilute in water, cost and unavailability of insecticides and equipment limit the effective control of these thrips. Incorporating thrips resistant genes into local adapted landraces could increase farmers‘ income. These new lines could be grown with minimal insecticide application. Participatory ...
    • Response of cowpea (Vigna unguiculata L.Walp) varieties to Bradyrhizobial strains (USDA 3384 and 3451) and phosphorus levels in the Sudan Savanna of Nigeria 

      Musa, M. (Bayero University, 2017-01)
      Field trials were conducted during the 2015 wet season at the Bayero University Kano Teaching and Research Farm (110 58’N, 8025’E and 475m above sea level) and National Institute of Horticultural Research Technology (NIHORT) Bagauda (lat. 120 08'N, long. 80 32'E, 500m above sea level). The study was conducted to determine the response of cowpea (Vigna unguiculata L. Walp) varieties to rhizobium and phosphorus levels in the sudan savannah of Nigeria. The treatments consisted of four cowpea varieties ...
    • Bio-ecology and systematics of the scale insect Stictococcus vayssierei Richard, 1971 (Hemiptera: Stictococcidae), a major pest of root and tuber crops in the Nigero-Congolian forest block 

      Doumtsop, F.A.R. (2021)
      Stictococcus vayssierei Richard, 1971 commonly known as the African root and tuber scale (ARTS), was first identified as an agricultural pest in the early 1980s. Following population outbreaks in Cameroon and the Democratic Republic of Congo in late 1980s – early 1990s, the insect is currently reported as one of the major pests threatening root and tuber crop production in Central Africa. Outbreaks can merely be viewed as symptomatic of some breakdown of internal organization and extrinsic factors ...
    • Comparative assessment of genetic diversity in tissue culture - and field - propagated white yam (Dioscorea rotundata) accession using molecular marker (SSRs) and morphological characterization 

      Abu, G.I. (Cross River University of Technology, 2018-04)
      This experiment was conducted at theInternational Institute of Tropical Agriculture (IITA), Ibadan. The objective of the study was to contribute to the understanding of Dioscorea rotundata maintained in vitro and field to observe if there could be any variability in their genetic material due to their different storage conditions by genotyping 43 accessions from in vitro and field populations using 11 microsatellite markers and 25 morphological descriptors to access variability within and between ...
    • Evaluation of drought tolerant maize hybrids for tolerance to heat and combined drought and heat stresses 

      Adegun, A.A. (University of Ibadan, 2019-12)
      Low maize yields and the impacts of climate change on maize production shows the need to improve yields in Sub-Saharan Africa. Thus the objective of this study is to evaluate DT maize hybrids under heat and combined heat and drought stresses and to determine the relationship between grain yield and other agronomical trait. In this study two groups of hybrids were used. Eighteen top cross maize hybrids, one local check and a standard check laid-out in alpha lattice of 5x4 with two replicates, the ...
    • Genetic analysis of extra-early yellow and orange quality protein maize (Zea mays L.) inbread lines under low nitrogen and Striga stresses 

      Abu, P. (University of Ghana, 2019-12)
      Low soil nitrogen (low-N) and Striga hermonthica (Del.) are major constrains hampering maize production in sub-Saharan Africa (SSA). Developing extra-early quality protein maize (QPM)-provitamin A hybrids that combine low-N tolerance with Striga resistance is crucial for addressing the food security and undernourishment challenges in SSA. The objectives of this study were to i) assess the genetic diversity among a group of extra-early yellow QPM and orange QPM-provitamin A maize inbred lines, ii) ...
    • Digitalization of smallholder value chain lending partnerships: an interplay of trust and inclusion 

      Agyekumhene, C. (Wageningen University and Research Center, 2021)
    • Contribution a la gestion agroecologique de Maruca vitrata Fab. et d'autres insectes ravageurs majeurs de la culture du niebe (Vigna unguiculata L. Walp.) dans les regions de Zinder et Maradi au Niger 

      Abdoulaye Zakari, O. (Universite Dan Dicko Dankoulodo De Maradi, 2020)
      Au Niger, le niébé (Vigna unguiculata L. Walp.) est une culture alimentaire importante mais son rendement est bas en raison de plusieurs contraintes biotiques et abiotiques. L’objectif de cette thèse est d’améliorer le rendement du niébé par la mise en place d’une stratégie écologique de lutte contre les principaux insectes ravageurs de la culture. Les activités suivantes ont été conduites : une enquête de base dans 19 villages des régions de Maradi et Zinder pour identifier les principales ...
    • Innovation intermediation in a digital age: broadening extension service delivery in Ghana 

      Munthali, N. (Wageningen University and Research Center, 2020)
      Classical extension focuses on linear transfer of technology. Globally, and in Ghana particularly, we have seen attempts to address the linearity of classical extension with the shift to broader extension service delivery approaches. From an innovation systems perspective innovation intermediation is suggested for extension organisations to function more effectively and respond to wider agricultural system constraints. This involves three broad facilitation roles which are demand articulation, ...
    • Genetic analysis of tuber yield and quality traits in white yam (Dioscorea rotundata Poir) 

      Norman, P.E.; Asfaw, A.A. (University of Ghana, 2019-12)
      The genetic progress in tuber yield and quality attributes of yam is constrained by prolonged breeding cycle, complex ploidy (2n=40, 60, 80), high heterozygousity, complex flowering pattern (dioecois and monoecious flowering and shy to flower), multi-species, low propagation ratio, biotic and abiotic factors. Genetic improvement of yam with high tuber yield, high dry matter content, starch and other food quality attributes using traditional and modern breeding techniques will contribute to the ...
    • Interseeding timing of cowpea (Vigna unguiculata L. Walp.) living mulch on weed diversity, physical soil properties and performance of maize (Zea mays L.) 

      Berdjour, A. (University of Development Studies, 2019)
      This trial was conducted to determine cowpea living mulch and maize maturity type effect on soil physical properties, maize yield and weed management. The study was a 3 x 4 factorial experiment laid out in Randomised Complete Block Design with 3 replications. Three maize maturity types: extra early Abontem, early Omankwa and medium Obatanpa and four living mulch systems: cowpea living mulch interseeded same day with maize (SDWM), cowpea living mulch interseeded 1 Week after planting maize (WAPM), ...
    • Evaluation of starches from selected yellow and white flesh cassava roots for noodles production 

      Akinde, H.A. (Federal University of Agriculture, Abeokuta, 2020)
      Cassava starch has been prospected in many food products manufacture. However, its suitability for making starch noodle has not been reported. Hence, this study was conducted to determine cassava starch‘s suitability in starch noodles production. The study was based on a completely randomized design with cassava variety as the main source of variation. The physicochemical properties [paste clarity (PCL), gel strength (GS), retrogradation], amylose content (AC), thermal properties [onset temperature, ...