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Journal and Journal Articles: Recent submissions
Now showing items 1141-1160 of 5271
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Application of CRISPR/Cas for diagnosis and management of viral diseases of banana
(2021)Viral diseases are significant biotic constraints for banana (Musa spp.) production as they affect the yield and limit the international movement of germplasm. Among all the viruses known to infect banana, the banana bunchy top virus and banana streak viruses are widespread and economically damaging. The use of virus-resistant bananas is the most cost-effective option to minimize the negative impacts of viral-diseases on banana production. CRISPR/Cas-based genome editing is emerging as the most ... -
Technological innovations for improving cassava production in sub-Saharan Africa
(2021-01)Cassava is crucial for food security of millions of people in sub-Saharan Africa. The crop has great potential to contribute to African development and is increasing its income-earning potential for small-scale farmers and related value chains on the continent. Therefore, it is critical to increase cassava production, as well as its quality attributes. Technological innovations offer great potential to drive this envisioned change. This paper highlights genomic tools and resources available in ... -
Opportunities and challenges for biofortification of cassava to address iron and zinc deficiency in Nigeria
(2021-03)Nigeria is the world's largest producer of cassava (Manihot esculenta), and its production is important to the country's economy. Cassava's edible storage roots act as a critical staple food for over 180 million Nigerians. Micronutrient deficiency presents a major public health issue in Nigeria and correlates with cassava consumption level across six-agro-ecological zones within the country. Though high in caloric value, cassava roots are deficient in minerals, placing populations that rely on ... -
Emergence of Maruca vitrata as a major pest of food legumes and evolution of management practices in Asia and Africa
(2021-01)Legume pod borer, Maruca vitrata, has emerged as a major pest on food legumes in Asia and Africa. It is an oligophagous pest, feeding on over 70 species in Fabaceae. We examine the species complex in Asia, Africa, Oceania, and the Americas, with an emphasis on molecular taxonomy. Studies on pheromone production and perception suggest the existence of pheromone polymorphism, especially in Asia and Africa. No Maruca-resistant varieties are available in the major food legumes including cowpea, ... -
Does agricultural cooperative membership impact technical efficiency of maize production in Nigeria: an analysis correcting for biases from observed and unobserved attributes
(2021)The formation of agricultural cooperatives has been widely promoted as an agricultural development policy initiative to help smallholder farmers cope with multiple production and marketing challenges. Using a nationally representative survey dataset of smallholder maize producers from rural Nigeria, this study assesses the impact of agricultural cooperative membership on technical efficiency (TE). We based our estimation approach on the combination of a newly developed sample selection stochastic ... -
Impacts on greenhouse gas balance and rural economy after agroecology development in Itasy Madagascar
(2020)Rural development projects to develop sustainable agriculture need to be assessed before engaging smallholder farmers at large scale. Data on agricultural systems to produce food, provide income for smallholders and reduce greenhouse-gas (GHG) emissions are scarce in Sub-Saharan Africa countries. Here, we assessed the potential of agroecological practices (AP) on economic benefits to farmers, GHG balance derived from agricultural activities, and efficiency of economic investments to mitigate GHG. ... -
Genotype by environment cultivar evaluation for cassava brown streak disease resistance in Tanzania
(2020-09)Cassava brown steak disease (CBSD), caused by Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), is the most important biotic constraint to cassava production in East and Central Africa. Concerted efforts are required to prevent further spread into West Africa as well as to reduce losses in areas already affected. The study reported here was part of a five-country (Kenya, Malawi, Mozambique, Tanzania and Uganda) programme that aimed to identify superior cassava ... -
Multiple small-effect alleles of Indica origin enhance high iron-associated stress tolerance in rice under field conditions in west Africa
(2020)Understanding the genetics of field-based tolerance to high iron-associated (HIA) stress in rice can accelerate the development of new varieties with enhanced yield performance in West African lowland ecosystems. To date, few field-based studies have been undertaken to rigorously evaluate rice yield performance under HIA stress conditions. In this study, two NERICA × O. sativa bi-parental rice populations and one O.sativa diversity panel consisting of 296 rice accessions were evaluated for grain ... -
Enhancing farmers’ agency in the global crop commons through use of biocultural community protocols
(2021)Crop genetic resources constitute a ‘new’ global commons, characterized by multiple layers of activities of farmers, genebanks, public and private research and development organizations, and regulatory agencies operating from local to global levels. This paper presents sui generis biocultural community protocols that were developed by four communities in Benin and Madagascar to improve their ability to contribute to, and benefit from, the crop commons. The communities were motivated in part by the ... -
Organic manure improves soybean response to rhizobia inoculant and p-fertilizer in northern Ghana
(2020-09)Inherently low concentrations of soil nutrients and erratic rainfall pattern in sub-Sahara Africa limit soybean response to rhizobia inoculant and P-fertilizer. The study was conducted to: (i) improve soybean response to rhizobia inoculation and P-fertilizer through the addition of organic manure; (ii) enhance rain water use efficiency and (iii) determine the economic viability of combined application of the three factors in soybean cropping systems in the Northern region of Ghana. A factorial ... -
Carotenoid profile and functional properties of flour blends from biofortified maize and improved soybean varieties for product developments
(2021)Biofortified maize has received increased attention from a nutraceutical perspective because of its bioactive phytochemical components, including carotenoids. However, biofortified maize is limiting in some amino acids which are present in soybeans; hence both crops are used as blends in food products. Thus, this study aimed to evaluate the carotenoids and functional properties of maize-soybean flour blends as influenced by biofortified maize variety. Flour blends were prepared from each maize ... -
Simple sequence repeat-based mini-core collection for white Guinea yam (Dioscorea rotundata) germplasm
(2021)A core subset with a small number of accessions representing the genetic diversity of the base collection plays a vital role in facilitating efficient utilization of plant genetic resources. This is particularly relevant for vegetatively propagated large plant size tuber crops with a long growing period, such as white Guinea yam (Dioscorea rotundata Poir.). For the efficient utilization of D. rotundata genetic resources, this study was aimed at developing a mini‐core collection from a core collection ... -
Genotype by environment interaction on resistance to cassava green mite associated traits and effects on yield performance of cassava genotypes in Nigeria
(2020-09-04)Cassava is the main source of carbohydrate for over 70% of the people in Nigeria, the world’s largest producer and consumer of the crop. The yields of cassava are, however, relatively low in Nigeria largely due to pests and disease infections that significantly lead to inconsistencies in productivity of cassava genotypes in various environments. Fifty-eight F1 hybrid cassava genotypes plus their two parents which served as check varieties were evaluated in three locations for two years (that is ... -
Harvesting time and roasting effects on colour properties, xanthophylls, phytates, tannins and vitamin C contents of orange maize hybrid
(2020)Biofortified maize varieties form an essential part of a nutritious diet; available evidence suggests that different processing methods may affect the final food products. The study aimed to evaluate the effects of processing (roasting) and harvesting time on the bioactive components (lutein, zeaxanthin, β-cryptoxanthin, phytate, tannin and vitamin C) and colour properties (L*, a*, b*), of biofortified orange maize. The orange maize hybrids used for the study were obtained from the International ... -
Quantitative assessment of trace and macro element compositions of cassava (Manihot esculenta) storage roots enriched with B-Carotene as influenced by genotypes and growing locations
(2020)Cassava’s important mineral contents depends on some factors, including genetic and growing locational factors. The study aimed to evaluate the influence of genotype and growing locations on the mineral concentrations in yellow-fleshed cassava root genotypes. Twenty-five pipeline yellow-fleshed cassava genotypes and three white-fleshed varieties (check samples) were planted at five different experimental fields for two seasons, each representing the major agroecological zones in Nigeria. Standard ... -
Taxonomic revision of the Afrotropical hover fly genus Senaspis Macquart (Diptera, Syrphidae)
(2020)The representatives of the Afrotropical hover fly genus Senaspis Macquart (Diptera) are revised. In total, ten species are recognized. Senaspis apophysata (Bezzi) is herewith placed as junior synonym of S. flaviceps Macquart, S. livida (Bezzi) is herewith placed as junior synonym of S. dentipes (Macquart) and S. griseifacies (Bezzi) is herewith placed as junior synonym of S. haemorrhoa (Gerstaecker). All species are redescribed and an identification key is provided. DNA barcoding analysis (7 ... -
Low-cost technology for recycling agro-industrial waste into nutrient-rich organic fertilizer using black soldier fly
(2021-01)Efforts to recycle organic waste using black soldier fly (BSF) larvae into high-quality alternative protein ingredients in animal feeds and organic fertilizers have gained momentum worldwide. However, there is limited information on waste manipulation to increase nutrient retention for enhanced larval performance and frass fertilizer quality. In the present study, brewer’s spent grain with a carbon to nitrogen (C/N) ratio of 11 (control) was amended with sawdust to obtain substrates with C/N ratios ... -
Challenges for ex Situ conservation of wild bananas: seeds collected in Papua New Guinea have variable levels of desiccation tolerance
(2020)Ex situ seed conservation of banana crop wild relatives (Musa spp. L.), is constrained by critical knowledge gaps in their storage and germination behaviour. Additionally, challenges in collecting seeds from wild populations impact the quality of seed collections. It is, therefore, crucial to evaluate the viability of seeds from such collecting missions in order to improve the value of future seed collections. We evaluate the seed viability of 37 accessions of seven Musa species, collected from ... -
Insights into microbially induced salt tolerance and endurance mechanisms (stem) in plants
(2020)Salt stress threatens the achievement of sustainable global food security goals by inducing secondary stresses, such as osmotic, ionic, and oxidative stress, that are detrimental to plant growth and productivity. Various studies have reported the beneficial roles of microbes in ameliorating salt stress in plants. This review emphasizes salt tolerance and endurance mechanisms (STEM) in microbially inoculated (MI) plants that ensure plant growth and survival. Well-established STEM have been documented ... -
Effectiveness of yellow maize testers with varying resistance reactions to Striga hermonthica for evaluating the combining ability of maize inbred lines
(2020)The choice of an appropriate tester is important for success in resistance hybrid breeding programs. Limited information is available on the most suitable testers that allow the selection of yellow endosperm maize inbred lines with good combining ability for resistance to witchweed (Striga hermonthica) and superior agronomic performance in hybrids targeted to areas infested with the parasite. Testcrosses of 30 Striga-resistant yellow endosperm maize inbred lines with three testers having varying ...
