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Journal and Journal Articles: Recent submissions
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RNAi technology for management of banana bunchy top disease
(2020-11)Banana bunchy top disease (BBTD) is one of the world's most destructive viral diseases of banana and plantain, causing up to 100% yield loss in severe cases. The disease is vectored by banana aphids (Pentalonia nigronervosa) and carried long distances through the movement of infected plant materials. The banana aphids harboring banana bunchy top virus (BBTV) present in banana producing regions are the sole vector and the most efficient method of transmitting the virus to the healthy plants. ... -
Rural transformation and the future of cereal-based agri-food systems
(2020-09)Rural transformation is an inevitable and fundamental process of development. However, the speed and dimensions of rural transformation can affect investments in major staples such as maize, wheat and rice, which continue to play an important role in agri-food systems around the globe. This paper investigates the impacts of rural transformation on the future of cereal-based agri-food systems which are not directly addressed in global agricultural assessment models such as IMPACT. In this study, ... -
Push-pull strategy combined with net houses for controlling cowpea insect pests and enhancing crop yields
(2021-03)Net houses can be used in tropical environments to protect crops such as cowpea against large insect pests, thereby avoiding pesticide treatments while sustainably mitigating the effects of climate change. We investigated a push-pull strategy to prevent small insect pest outbreaks in a net house. The push component consisted of two stimulus plants, i.e. Cymbopogon citratus and Tagetes minuta, and the pull stimuli consisted of visual cues from blue and yellow sticky traps. Field experiments were ... -
Selected shade tree species improved cocoa yields in low-input agroforestry systems in Ghana
(2022-10)CONTEXT Cocoa agroforestry systems differ in the diversity of shade tree species composition. Though cocoa benefits from shade, there is a lack of species-specific information on shade trees that enhance soil fertility and yield. OBJECTIVE We examined how soil characteristics and cocoa yield were affected by eight commonly retained forest tree species, compared with unshaded control plots over a 3-year period. METHODS Using 74 circular plots from 10 cocoa farms in the Western region of Ghana, we ... -
Genome sequence of the banana aphid, Pentalonia nigronervosa Coquerel (Hemiptera: Aphididae) and its symbionts
(2020-12-01)The banana aphid, Pentalonia nigronervosa Coquerel (Hemiptera: Aphididae), is a major pest of cultivated bananas (Musa spp., order Zingiberales), primarily due to its role as a vector of Banana bunchy top virus (BBTV), the most severe viral disease of banana worldwide. Here, we generated a highly complete genome assembly of P. nigronervosa using a single PCR-free Illumina sequencing library. Using the same sequence data, we also generated complete genome assemblies of the P. nigronervosa symbiotic ... -
The response of climbing bean to fertilizer and organic manure in the northern province of Rwanda
(2020-10)Climbing beans play a central role in food security of rural households in the densely populated highlands of East and Central Africa. Soil fertility degradation and the lack of nutrient inputs are major limitations to yield of beans and other crops. We conducted field trials in Northern Rwanda in Kinoni and Muko villages to evaluate the effect of mineral N, P, and K fertilizers (both alone and in combination) and farmyard manure on nitrogen fixation and grain yields of climbing bean in smallholder ... -
Can a combination of UAV-derived vegetation indices with biophysical variables improve yield variability assessment in smallholder farms?
(2020-12-09)The rapid assessment of maize yields in a smallholder farming system is important for understanding its spatial and temporal variability and for timely agronomic decision-support. We assessed the predictability of maize grain yield using unmanned aerial/air vehicle (UAV)-derived vegetation indices (VI) with (out) biophysical variables on smallholder farms. High-resolution imageries were acquired with UAV-borne multispectral sensor at four and eight weeks after sowing (WAS) on 31 farmer managed ... -
Realizing Inclusive SAI: contextualizing indicators to better evaluate gender and intergenerational inequity in SAI processes and outcomes – cases from Southern and western Africa
(2021)Despite increasing sustainable agricultural intensification (SAI) investments, indicators for detecting gender and intergenerational inequities in SAI costs and benefits sharing often remain overgeneralized, theoretical, or locally irrelevant. We examine the relative value of, and how to, customize standard SAI indicators to detect such inequities in specific socio-cultural contexts to enhance data collection for evidence-based decision making in fostering gender/youth inclusive SAI. Using focus-group ... -
Genetic diversity, population structure and inter-trait relationships of combined heat and drought tolerant early-maturing maize inbred lines from west and central Africa
(2020-09-04)Adequate knowledge and understanding of the genetic diversity and inter-trait relationships among elite maize inbred lines are crucial for determining breeding strategies and predicting hybrid performance. The objectives of this study were to investigate the genetic diversity of 162 early maturing white and yellow tropical maize inbred lines, and to determine the population structure, heterotic groups and inter-trait relationships among the lines. Using 9684 DArT single nucleotide polymorphism ... -
Bio-protective effect of a root-nodulating Rhizobium etli strain in common bean (Phaseolus vulgaris) against Meloidogyne incognita and Radopholus similis in an in vitro autotrophic tripartite culture system
(2020)The bio-protective effect of a root-nodulating strain (CNPAF 512) of the nitrogen-fixing rhizobium, Rhizobium etli, against both a sedentary (Meloidogyne incognita) and a migratory (Radopholus similis) endoparasitic nematode in common bean (Phaseolus vulgaris) was examined using an in vitro autotrophic tripartite culture system. Two in vitro assays were carried out with each of the nematode species. Each assay consisted of two treatments: the plants were either inoculated with the rhizobial strain ... -
Identification of QTLs for grain yield and other traits in tropical maize under Striga infestation
(2020)Striga is an important biotic factor limiting maize production in sub-Saharan Africa and can cause yield losses as high as 100%. Marker-assisted selection (MAS) approaches hold a great potential for improving Striga resistance but requires identification and use of markers associated with Striga resistance for adequate genetic gains from selection. However, there is no report on the discovery of quantitative trait loci (QTL) for resistance to Striga in maize under artificial field infestation. In ... -
Opportunities and constraints facing fish production system in DR Congo
(2019-12)The current aquaculture production systems in the village environment and their constraints and opportunities were studied to understand the reasons for the decrease in the number of fishponds in South Kivu, eastern DR Congo. . Little is known about fish production in South Kivu; thus, this study was carried out in two phases: a survey, a follow-up of the farms over the course of a year and a literature review. Accordingly, 305 aquaculturists from three territories were interviewed from May to ... -
Quantification of selected anti - nutrients and bioactive compounds in African Bambara Groundnut (Vigna subterranea (L.) verdc.)
(2018)Bioactive compounds in plants, being secondary metabolites are important phyto-chemicals, that form the basis of modern pharmacology and medical treatment because it has natural beneficial compounds such as in nutraceuticals, micronutrients e.t.c. Neglected legumes like Bambara groundnut (Vigna subterranea (L.) Verdc.) can serve as a high nutrient pulse and also as food supplements. However, despite the fact that Bambara groundnut contains these beneficial bioactive compounds, it also has some ... -
Morphological characterisation of selected African accessions of bambara groundnut (Vigna subterranea (L.) verdc.)
(2017)Three hundred (300) accessions of Bambara groundnut (Vigna subterranea (L.) Verdc) among the 1973 maintained in the global repository at the International Institute of Tropical Agriculture (IITA), Ibadan, genebank were selected for this study. Two to three seeds of each accession were planted during the 2014 / 2015 planting season at IITA, Ibadan, Nigeria. Seedlings were thinned to a single plant prior to flowering. Thirty - seven (37) agro-morphological parameters, representing 28 quantitative ... -
Evaluation of nutrient parameters of selected African accessions of Bambara groundnut (Vigna subterranea (L.) verdc.)
(2017)Developing countries, especially in Africa are facing challenges of malnourished conditions and food insecurity generally. Nutrients, being components of food ingredient required for survival, normal body function and satisfying the physiological and dietary requirements of the body metabolism [38]. Hence, for meaningful growth and developments in man, the type and amount of nutrients intake and its rate of absorption or level is crucial. However, much emphases and consumption pattern in Africa ... -
Influence of drying methods on heavy metal composition and microbial load of plantain chips
(2022)Mature unripe plantain is usually processed into chips using the traditional sun-drying method without considering consumer safety. Thus, there is a need to assess the influence of solar tent and open sun drying on the heavy metal composition and microbial load of plantain chips. Thirty samples of dried plantain chips were collected randomly from 10 processing centers in Akure South and Idanre Local Government Areas of Ondo State, Nigeria. In addition, four popularly consumed plantain varieties ... -
From fruit growth to ripening in plantain: a careful balance between carbohydrate synthesis and breakdown
(2022-08-11)In this study, we aimed to investigate for the first time different fruit development stages in plantain banana in order gain insights into the order of appearance and dominance of specific enzymes and fluxes. We examined fruit development in two plantain banana cultivars during the period between 2–12 weeks after bunch emergence using high-throughput proteomics, quantification of major metabolites, and analyses of metabolic fluxes. Starch synthesis and breakdown are processes that take place ... -
Can improved cassava genotypes from the breeding program substitute the adopted variety for gari production? Biophysical and textural attributes approach
(2022)The use of the biophysical and textural attributes of gari/eba to determine the possible substitution of an adopted cassava variety (TMBE419) with the improved genotypes from the breeding program was evaluated in this study. Standard methods were used for the characterization of the biophysical and textural attributes of the gari/eba from dierent cassava roots. It was observed that the mean of the biophysical attributes of the gari is swelling power (SWP) 12.46%, dispersibility 59.70%, water ... -
Contribution of maize-based products to the livelihood of smallholder processors in rural northern Nigeria
(2022)In the smallholder value chains of maize, diversification of utilisation is an essential strategy towards enhancing the benefits drivable from the increase in maize production. This article identifies the contribution of maize-based products on poverty level among smallholder processors. The study, which was conducted in 30 rural communities in northern Nigeria, involved Focus Group Discussions and survey of 300 smallholder processors of maize-based products. Descriptive and inferential analyses ...