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Journal and Journal Articles: Recent submissions
Now showing items 1301-1320 of 5271
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Evaluating the distributional impacts of drought-tolerant maize varieties on productivity and welfare outcomes: an instrumental variable quantile treatment effects approach
(2019-12-23)In an attempt to go beyond the conventional mean impact assessment of agricultural interventions, this paper examines the distributional impacts of adoption of drought-tolerant maize varieties (DTMVs) on the productivity and welfare outcomes of rural farming households in Nigeria. The study employed a conditional instrumental variable quantile treatment effects approach to control for selection bias that may arise from both observed and unobserved factors. The empirical findings revealed that ... -
Sexual communication of Spodoptera frugipera from west Africa: adaptation of an invasive species and implications for pest management
(2020-02-19)The pest species Spodoptera frugiperda, which is native to North and South America, has invaded Africa in 2016. The species consists of two strains, the corn-strain and rice-strain, which differ in their sexual communication. When we investigated populations from Benin and Nigeria, consisting of corn-strain and rice-corn-hybrid descendants, we found no strain-specific sexual communication differences. Both genotypes exhibited the same pheromone composition, consisting of around 97% (Z)-9-tetradecenyl ... -
Plant tissue analysis as a tool for predicting fertiliser needs for low cyanogenic glucoside levels in cassava roots: an assessment of its possible use
(2020-02-13)The use of plant tissue analysis as a tool for attaining low cyanogenic glucoside levels in cassava roots, has hardly been investigated. Just as the quality of crops is improved through the use of plant tissue analysis, the same can probably be done to consistently attain the lowest possible cyanogenic glucoside levels in cassava roots. High levels of cyanogenic glucosides in consumed fresh cassava roots or in their products have the potential of causing cyanide intoxication, hence the need to ... -
Metagenomic insights of the root colonizing microbiome associated with symptomatic and non-symptomatic bananas in fusarium wilt infected fields
(2020-02-18)Plants tissues are colonized by diverse communities of microorganisms called endophytes. They are key determinants of plant production and health, for example by facilitating nutrient exchanges or limiting disease development. Endophytic communities of banana plants have not been studied until very recently, and their potential role in disease development has not been explored so far. Roots from symptomatic and non-symptomatic banana plants were sampled from fields infected by Fusarium oxysporum ... -
Optimizing soil fertility management strategies to enhance banana production in volcanic soils of the northern highlands, Tanzania
(2020-02-18)Banana is an important crop in high altitude areas of Tanzania, grown widely both as a food staple and as the main source of income. However, its production is constrained by low soil fertility, a result of gradual nutrient mining by the crop. Currently, soil fertility management in banana-based farming systems in the country relies mainly on applications of animal manure. However, the amount of manure produced in most farms is not enough to replenish soil fertility due to the small number of ... -
Functional biology and molecular mechanisms of host-pathogen interaction for aflatoxin contamination in groundnut (Arachis hypogaea L.) and maize (Zea mays L.)
(2020-03-03)Aflatoxins are secondary metabolites produced by soilborne saprophytic fungus Aspergillus flavus and closely related species that infect several agricultural commodities including groundnut and maize. The consumption of contaminated commodities adversely affects the health of humans and livestock. Aflatoxin contamination also causes significant economic and financial losses to producers. Research efforts and significant progress have been made in the past three decades to understand the genetic ... -
Assessment of the suitability of different cassava varieties for gari and fufu flour production in Liberia
(2020)Different cassava varieties are available in Liberia, but there is little knowledge of their product suitability. Hence, the need to assess the potentials of these varieties to produce gari and fufu flour. The two products from ten improved and two local cassava varieties were characterized based on their yield and chemical, pasting and functional properties using standard methods. The results showed that TMS 96/0097 (gari 27.54%) and Butter cassava (fufu flour 27.35%) have the highest percentage ... -
Molecular breeding for nutritionally enriched maize: status and prospects
(2020-02-21)Maize is a major source of food security and economic development in sub-Saharan Africa (SSA), Latin America, and the Caribbean, and is among the top three cereal crops in Asia. Yet, maize is deficient in certain essential amino acids, vitamins, and minerals. Biofortified maize cultivars enriched with essential minerals and vitamins could be particularly impactful in rural areas with limited access to diversified diet, dietary supplements, and fortified foods. Significant progress has been made ... -
A review of inclusive business models and their application in aquaculture development
(2020-01-30)achieving the Sustainable Development Goals, value chains must become more inclusive. Smallholders and other local value chain actors are often constrained by circumstances and market failures in the global aquaculture industry. Integrating these actors into aquaculture value chains through inclusive business models (IBMs) is often touted as a solution to sustainable and ethical trade and business that can generate development outcomes. We reviewed 36 papers under seven business models commonly ... -
Breeding new sweetpotato genotypes combining elevated content of two antagonistic traits of high dry matter and beta-carotene content in a high root yield background
(2019)This study was embarked upon to stack two key but inversely associated sweetpotato traits (dry matter and beta-carotene content) through conventional breeding methods. Thirty-seven elite sweetpotato genotypes were evaluated for both traits, and 15 parents comprising five orange-, five yellow- and five white-fleshed genotypes were selected from the 37 for hybridization. Using bi-parental mating fashion, an F1 progeny population for both traits was developed. Of the 13 families developed, eight ... -
Analyse multi-niveaux des freins a l'adoption de la certification du cacao au Cameroun
(2019-12)Les exigences européennes sur la qualité du cacao conduisent au développement de la certification, pour améliorer la production et la gestion post-récolte des fèves. Cependant, la certification reste peu développée au Cameroun. Cet article mobilise le modèle de la transition sociotechnique pour analyser les déterminants d’adoption de la certification. Des entretiens auprès de 11 acteurs de la filière cacao ont été menés, ainsi qu’une enquête auprès de 90 producteurs. Les résultats mettent en exergue ... -
Diversity, use and production of farmers' varieties of common bean (Phaseolus vulgaris L., Fabaceae) in southwestern and northeastern Ethiopia
(2020)Legumes are a critical component of many agricultural systems and a major contributor to global food systems. Common bean (Phaseolus vulgaris L.) is the most widely grown legume crop in Ethiopia. It is an important source of food, income, and soil fertility management in southwestern (SW) and northeastern (NE) Ethiopia, and used as medicine, fodder, and honeybee forage in the NE. Diversity and use of farmers’ varieties of common bean (Phaseolus vulgaris) bean were investigated in five administrative ... -
Documenting museum records of west African Coccinellidae (Coleoptera) in Benin and Senegal
(2020)Background This work provides a preliminary inventory of West African Coccinellidae. This was based on the West African Coccinellidae (WAC) specimens in the holdings of insect collections at the Laboratoire de Zoologie des Invertébrés Terrestres at the Institut Fondamental d’Afrique Noire Cheikh Anta Diop (IFAN), Senegal and the Biodiversity Center at the International Institute of Tropical Agriculture (IITAB), Benin. New information A total of 129 species representing 11 tribes and 40 ... -
Stakeholders’ perceptions on sustainability transition pathways of the cocoa value chain towards improved livelihood of small-scale farming households in Cameroon
(2020)Given the persistent poor livelihood of cocoa-farming households, future climate predictions and the worldwide demand pressure for higher cocoa quality and productivity, there is still a strong need to find new approaches that guarantee a sustainable cocoa future in cocoa-producing countries amongst which Cameroon is one of them. This exploratory research investigates potential future pathways for the cocoa sector in Cameroon by mapping the perceptions of actors involved in the socio-technical ... -
Metabolite database for root, tuber, and banana crops to facilitate modern breeding in understudied crops
(2020)Roots, tubers, and bananas (RTB) are vital staples for food security in the world's poorest nations. A major constraint to current RTB breeding programmes is limited knowledge on the available diversity due to lack of efficient germplasm characterization and structure. In recent years large‐scale efforts have begun to elucidate the genetic and phenotypic diversity of germplasm collections and populations and, yet, biochemical measurements have often been overlooked despite metabolite composition ... -
Social-cognitive factors influencing household decisions to grow orange-fleshed sweet potato in Uganda
(2020-01)This study examined the role of social-cognitive factors in farmers’ decisions to cultivate orange-fleshed sweetpotato as a food-based approach to alleviating vitamin A deficiency among rural households in Uganda. Cross-sectional survey data collected from 341 randomly selected household level decision-makers drawn from two rural districts in Uganda were analysed using hierarchical regression. Perceived capability and perceived social approval significantly predicted household decisions to grow ... -
Characterizing fruit ripening in plantain and Cavendish bananas: a proteomics approach
(2020)The fruit physiology of banana cultivars other than Cavendish is poorly understood. To study the ripening process, samples were taken daily from plantain and Cavendish bananas and the ripening stages were determined. We present data from the green to the fully mature stage. By analyzing the protein abundances during ripening we provide some new insights into the ripening process and how plantains fruits are different. Multivariate analysis of the proteins was performed correlated to the starch ... -
Detection and diversity of maize yellow mosaic virus infecting maize in Nigeria
(2019-12)Maize yellow mosaic virus (MaYMV; genus Polerovirus; family Luteoviridae) was recently characterized from maize in China and subsequently detected in mixed infection with sugarcane mosaic virus (genus Potyvirus; family Potyviridae) in sugarcane and itch grass in Nigeria. This study was conducted to understand the status and genetic diversity of MaYMV in maize fields in the northern guinea savannah region of Nigeria. A survey was conducted in 2017 and maize (n = 90) and itch grass (n = 10) plants ... -
Efficiency of food-based attractants for monitoring tephritid fruit flies diversity and abundance in mango systems across three west African agro-ecological zones
(2019)Food baits are effective and widely used tools for monitoring diversity and abundance of tephritid fruit flies. Four food-baits—Nulure, BioLure, Mazoferm at 3 and 6%, and Torula yeast—were used in multi-lure traps over a 4-yr period in mango orchards in three Benin agro-ecological zones (AEZ) representing a large swath of environments in western Africa. Twelve tephritid fruit fly species were captured during the trials, with the highest richness in the Forest Savannah Mosaic (FSM), followed by the ... -
Does institution type affect access to finance for cassava actors in Nigeria?
(2020)The cassava system in Nigeria is developing, with increasing attention to its potential positive outcomes. However, credit access is a major problem in expanding productive activities of the different actors across the value chains of cassava products. This study investigates the extent of access to credit by cassava actors with respect to the different financial institutions in the country using data obtained from a sample of 168 actors, including producers, processors, marketers, fabricators and ...
