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Journal and Journal Articles: Recent submissions
Now showing items 1001-1020 of 5157
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Diversite des trajectoires de l'agriculture biologique au Cameroun
(2020)Dans un contexte de renouvellement des enjeux technologiques de l'agriculture africaine, l'agriculture biologique représente une option de transition potentielle. Cette étude analyse les conditions de son développement au Cameroun. Elle mobilise le modèle multi-niveaux de la théorie des transitions sociotechniques. Elle est documentée par des enquêtes réalisées entre 2016 et 2018. Les résultats soulignent le rôle central des institutions dans l'activation des trajectoires de l'agriculture biologique. ... -
Optimizing sowing density-based management decisions with different nitrogen rates on smallholder maize farms in northern Nigeria
(2021-01-18)In this study, the CERES-Maize model was calibrated and evaluated using data from 60 farmers’ fields across Sudan (SS) and Northern Guinea (NGS) Savannas of Nigeria in 2016 and 2017 rainy seasons. The trials consisted of 10 maize varieties sown at three different sowing densities (2.6, 5.3, and 6.6 plants m−2) across farmers’ field with contrasting agronomic and nutrient management histories. Model predictions in both years and locations were close to observed data for both calibration and evaluation ... -
Disease incidence and severity in cowpea lines evaluated for resistance to single and multiple infections of endemic viruses in Nigeria
(2020-10)Cowpea (Vigna unguiculata (L.) Walp) is susceptible to several viruses in West Africa. Cowpea viral diseases are mainly controlled through the use of resistant cultivars. Co-infection with more than one virus is frequent in the fields and the resultant synergistic effect often compromises host resistance identified by screening against individual viruses under field or controlled conditions. In this study, eight improved cowpea breeding lines, identified as resistant to single infections and a ... -
Maize–legume strip cropping effect on productivity, income, and income risk of farmers in northern Ghana
(2021)Maize (Zea mays L.)–legume intercropping is common cropping system among smallholder farmers in West Africa. However, little is known about the income risk reduction associated with maize–legume strip cropping in West Africa. A 3‐yr study was conducted in Upper West and Northern regions of Ghana to determine the effect of maize–legume strip cropping on productivity, income, and income risk using a randomized complete block design with five replications in each region. Seven treatments were used: ... -
Genetic diversity of white yam (Dioscorea rotundata Poir) accessions maintained in tissue culture and cultivated in field using Simple Sequence Repeat (SSR) Markers and Morphological Characterization
(2021)Dioscorea rotundata is a staple food crop for millions of people in the tropical and subtropical regions. In vitro germplasm conservation is a very useful tool in yam improvement strategies but very little is known about the genetic integrity and stability of in-vitro conserved yam plants. In this study, 42 accessions from in vitro and field populations were genotyped using 11 microsatellite markers and 23 morphological descriptors to assess variability within and between accessions. Out of the ... -
Data set of smallholder farm households in banana-coffee-based farming systems containing data on farm households, agricultural production and use of organic farm waste
(2021-04)The data was collected in the Karagwe and Kyerwa districts of the Kagera region in north-west Tanzania. It encompasses 150 smallholder farming households, which were interviewed on the composition of their household, agricultural production and use of organic farm waste. The data covers the two previous rainy seasons and the associated vegetation periods between September 2016 and August 2017. The knowledge of experts from the following institutions was included in the discussion on the selection ... -
Enhancing drought tolerance and Striga hermonthica resistance in maize using newly derived inbred lines from the wild maize relative, Zea diploperennis
(2021)Recurrent drought and Striga hermonthica (Del.) Benth parasitism constrains maize production in sub-Saharan Africa (SSA). Transfer of resistance genes from wild relatives can improve resistance to drought and Striga in tropical maize. The objectives of this study were to (i) determine the combining ability of 12 extra-early yellow maize inbreds derived from Zea diploperennis and tropical maize germplasm; (ii) classify the inbreds into heterotic groups using heterotic grouping based on the general ... -
Validation of diagnostic markers for streak virus disease resistance in maize
(2021)Maize streak virus (MSV) is responsible for streak disease of maize and poses a serious threat to maize production in sub-Saharan Africa. Polygenic resistance to MSV has become an essential requirement in modern maize cultivars to mitigate yield losses. Many single nucleotide polymorphism (SNP) markers linked to putative MSV resistance loci have been identified for use in forward breeding. This study aimed to validate, using the high-throughput kompetitive allele specific PCR (KASP) assay, the ... -
Genetic diversity and population structure of early and extra-early maturing maize germplasm adapted to sub-Saharan Africa
(2021)Background Assessment and effective utilization of genetic diversity in breeding programs is crucial for sustainable genetic improvement and rapid adaptation to changing breeding objectives. During the past two decades, the commercialization of the early and extra-early maturing cultivars has contributed to rapid expansion of maize into different agro-ecologies of sub-Saharan Africa (SSA) where maize has become an important component of the agricultural economy and played a vital role in food and ... -
Agro-ecology, resource endowment and indigenous knowledge interactions modulate soil fertility in mixed farming systems in central and western Ethiopia
(2021)Site‐specific soil fertility management requires a fundamental understanding of factors that modulate soil fertility variability in the local context. To verify this assumption, this study hypothesized that soil fertility variability across two regions in Central and Western Ethiopia is determined by inter‐related effects of agro‐ecological zones and farmers’ resource endowment (‘wealthy’ versus ‘poor’ farmers). Mid‐infrared spectroscopy coupled to partial least squares regression (midDRIFTS‐PLSR) ... -
Prevalence of aflatoxin- and fumonisin-producing fungi associated with cereal crops grown in Zimbabwe and their associated risks in a climate change scenario
(2021)In most sub-Saharan African countries, staple cereal grains harbor many fungi and some produce mycotoxins that negatively impact health and trade. Maize and three small grain cereals (sorghum, pearl millet, and finger millet) produced by smallholder farmers in Zimbabwe during 2016 and 2017 were examined for fungal community structure, and total aflatoxin (AF) and fumonisin (FM) content. A total of 800 maize and 180 small grain samples were collected at harvest and during storage from four ... -
Plant density and nitrogen responses of maize hybrids in diverse agroecologies of west and central Africa
(2021)Maize (Zea mays L.) production in West and Central Africa is constrained by drought, low soil-N and Striga infestation. Breeders in the region have developed and commercialized extra-early and early-maturing hybrids (E-EH and EH), which combine high yield potentials with tolerance/resistance to the three stresses. Hybrids of both maturity groups are new to the farmers; thus, the urgent need to recommend appropriate agronomic practices for these hybrids. We investigated the responses of four hybrids ... -
Household welfare impacts of an agricultural innovation platform in Uganda
(2020)Technical approaches to food production are important to the food security of growing populations in developing countries. However, strategic investments in research and farm‐level adoption require greater coherence in agricultural, societal, and local policies. The Agricultural Innovation System (AIS) and formation of the Cassava Innovation Platform (CIP) in Uganda were designed to stimulate interactions between researchers and farmers, leading to the development of improved cassava varieties ... -
Correlation of the sensory attributes of thick yam paste (amala) and the functional and pasting properties of the flour as affected by storage periods and packaging materials
(2020-10)This study aims to evaluate the relationship between the sensory attributes of amala and the functional and pasting properties of the yam flour (YF) as affected by storage periods and packaging materials. Results showed that all the functional (except swelling power) and pasting properties of the YF were significantly affected (p < .05) by the storage periods. The peak and trough viscosities of polypropylene woven sack (PPS) packaged YF have significant negative correlation with the texture (r = ... -
Delineation of soil fertility management zones for site-specific nutrient management in the maize belt region of Nigeria
(2020)Site-specific nutrient management can reduce soil degradation and crop production risks related to undesirable timing, amount, and type of fertilizer application. This study was conducted to understand the spatial variability of soil properties and delineate spatially homogenous nutrient management zones (MZs) in the maize belt region of Nigeria. Soil samples (n = 3387) were collected across the area using multistage and random sampling techniques, and samples were analyzed for pH, soil organic ... -
Present status and perspective on the future use of aflatoxin biocontrol products
(2020)Aflatoxin contamination of important food and feed crops occurs frequently in warm tropical and subtropical regions. The contamination is caused mainly by Aspergillus flavus and A. parasiticus. Aflatoxin contamination negatively affects health and trade sectors and causes economic losses to agricultural industries. Many pre- and post-harvest technologies can limit aflatoxin contamination but may not always reduce aflatoxin concentrations below tolerance thresholds. However, the use of atoxigenic ... -
Assessment of willingness-to-pay for Aflasafe KE01, a native biological control product for aflatoxin management in Kenya
(2020)Contamination of key staples with aflatoxins compromises the quality of food and feed, impedes trade, and negatively affects the health of consumers whereas acute exposure can be fatal. This study used the Contingent Valuation Method (CVM) on a sample of 480 farmers in counties prone to aflatoxin contamination to assess the willingness to pay (WTP) by farmers for Aflasafe KE01, a promising biological control product for the management of aflatoxin contamination of key staples in Kenya, compare its ... -
Aflasafe SN01 is the first biocontrol product approved for aflatoxin mitigation in two nations, Senegal and The Gambia
(2020)Aflatoxin contamination is caused by Aspergillus flavus and closely related fungi. In The Gambia, aflatoxin contamination of groundnut and maize, two staple and economically important crops, is common. Groundnut and maize consumers are chronically exposed to aflatoxins, sometimes at alarming levels, and this has severe consequences on their health and productivity. Aflatoxin contamination also impedes commercialization in local and international premium markets. In neighboring Senegal, an aflatoxin ... -
Functional diversity of soil nematodes in relation to the impact of agriculture - a review
(2021-02-04)The analysis of the functional diversity of soil nematodes requires detailed knowledge on theoretical aspects of the biodiversity–ecosystem functioning relationship in natural and managed terrestrial ecosystems. Basic approaches applied are reviewed, focusing on the impact and value of soil nematode diversity in crop production and on the most consistent external drivers affecting their stability. The role of nematode trophic guilds in two intensively cultivated crops are examined in more detail, ... -
The functional and pasting properties of unripe plantain flour, and the sensory attributes of the cooked paste (amala) as affected by packaging materials and storage periods
(2020)Unripe plantain flour (UPF) is hygroscopic and gets spoilt if not correctly processed, packaged and stored. Thus, the need to study the functional and pasting properties of the UPF, and the sensory attributes of the cooked paste (amala) as affected by packaging materials and storage periods. The UPF was produced using the standard method, packaged in a polypropylene woven sack (PPS) and polyvinyl chloride container (PVC), stored for 20-weeks at room temperature and analyzed at 4-weeks intervals. ...
