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Journal and Journal Articles: Recent submissions
Now showing items 1261-1280 of 5271
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Food access deficiencies in sub-Saharan African: prevalence and implications for agricultural interventions
(2019)Our understanding of food security in sub-Saharan Africa (SSA) has been hampered by limitations in the temporal and spatial representativeness of data. Food balance sheets provide scalable estimates of per capita food availability, but fail to represent food access, stability and their causal linkages. In contrast, rural household surveys represent detailed conditions for one or multiple points in time, but are influenced by survey timing and are often limited in geographical coverage. This study ... -
Factors influencing participation dynamics in research for development interventions with multi-stakeholder platforms: a metric approach to studying stakeholder participation
(2019)Multi-stakeholder platforms have become mainstream in projects, programmes and policy interventions aiming to improve innovation and livelihoods systems, i.e. research for development interventions in low- and middle-income contexts. However, the evidence for multistakeholder platforms’ contribution to the performance of research for development interventions and their added value is not compelling. This paper focuses on stakeholder participation as one of the channels for multi-stakeholder ... -
Evaluation of the American yam bean (Pachyrhizus spp.) for storage root yield across varying eco-geographic conditions in Uganda
(2019)The American yam bean (Pachyrhizus spp.) is a legume crop that is exclusively used for its storage roots. The seeds are inedible due to presence of toxic rotenone. It produces high storage root yields comparable of major root crops like cassava or sweetpotato. And flower pruning more than doubles its root yield performance. Using twenty five yam bean accessions, the current study aimed to determine root yield stability and adaptability, and presence of yam bean production mega environments in ... -
Distribution of Pseudocercospora species causing Sigatoka leaf diseases of banana in Uganda and Tanzania
(2020-01)Sigatoka leaf diseases are a major constraint to banana production. A survey was conducted in Tanzania and Uganda to assess the distribution of Pseudocercospora species and severity of Sigatoka leaf diseases. Pseudocercospora species were identified using species‐specific primers. Sigatoka‐like leaf diseases were observed in all farms and on all cultivars, but disease severity varied significantly (P < 0.001) between countries, districts/regions within countries, altitudinal ranges and banana ... -
Distribution and diversity of viruses infecting yams (Dioscorea spp.) in Cameroon
(2019-12)Yam (Dioscorea spp.) is an important food crop cultivated for its edible tubers in Cameroon. Surveys were conducted in Cameroon to determine the incidence and severity of yam mosaic disease and associated viruses in 124 yam farms in four agro-ecological zones in 2014 and 2016. Dioscorea rotundata, D. cayenensis, D. alata, D. Dumetorum and D. bulbifera were most frequently detected yam species in the fields. Symptoms of virus disease were observed on 81.5% of the farms surveyed and the disease ... -
Changes in heterosis of maize (Zea mays L.) varietal cross hybrids after four cycles of reciprocal recurrent selection
(2019)Two improved tropical maize composites, TZL COMP3 and TZL COMP4; representing complementary heterotic pools have been subjected to four cycles of reciprocal recurrent selection (RRS) for two decades to enhance varietal cross performance. The objectives of this study were to evaluate the effect of selection on genetic gain in heterosis for grain yield and other agronomic traits of these composites. Ten parental populations representing the C0 to C4 of each composite and their crosses plus a varietal ... -
Assessment of genetic diversity for drought, heat and combined drought and heat stress tolerance in early maturing maize landraces
(2019)Climate change is expected to aggravate the effects of drought, heat and combined drought and heat stresses. An important step in developing ‘climate smart’ maize varieties is to identify germplasm with good levels of tolerance to the abiotic stresses. The primary objective of this study was to identify landraces with combined high yield potential and desirable secondary traits under drought, heat and combined drought and heat stresses. Thirty-three landraces from Burkina Faso (6), Ghana (6) and ... -
A simple and rapid protocol for the genetic transformation of Ensete ventricosum
(2019-12)Enset (Ensete ventricosum), also known as Ethiopian banana, is a food security crop for more than 20 million people in Ethiopia. As conventional breeding of enset is very challenging, genetic engineering is an alternative option to introduce important traits such as enhanced disease resistance and nutritional value. Genetic transformation and subsequent regeneration of transgenic enset has never been reported mainly due to challenges in developing transformation protocols for this tropical species. ... -
A detached leaf assay to rapidly screen for resistance of maize to Bipolaris maydis, the causal agent of southern corn leaf blight
(2019)Southern corn leaf blight (SCLB), caused by the fungus Bipolaris maydis, is a disease that significantly affects maize productivity across the globe. A detached leaf assay (DLA) was developed to rapidly assess maize resistance to SCLB. Several experiments were conducted to: (i) identify a highly virulent B. maydis isolate; and to determine the most appropriate (ii) phytohormone to maintain viability of maize leaf tissue, (iii) leaf age for the assay, and (iv) inoculum concentration. Once optimized, ... -
Diagnosis of crop secondary and micro-nutrient deficiencies in sub-Saharan Africa
(2019)Crop production in sub-Saharan Africa has numerous biotic and abiotic constraints, including nutrient deficiencies. Information on crop response to macronutrients is relatively abundant compared with secondary and micronutrients (SMN). Data from 1339 trial replicates of 280 field trials conducted from 2013 to 2016 in 11 countries were analyzed for the diagnosis of SMN deficiencies. The diagnostic data included relative yield response (RYR) and soil and foliar test results. The RYR to application ... -
Combining ability for grain yield, agronomic traits and striga hermonthica resistance of yellow endosperm maize
(2018)Maize production is constrained by Striga hermonthica in Mali leading to high yield losses. Breeding resistant hybrid maize is a promising alternative for increasing farmers’ income. The objective of this study was to evaluate the response of test crosses to Striga hermonthica and identify high yielding and adopted hybrid. Forty-five F1 hybrids and three checks were evaluated under Striga-infested and Striga-free conditions in Sanankoroba and Sotuba rainy season. Data collection was carried on ... -
Aflatoxin-producing fungi associated with pre-harvest maize contamination in Uganda
(2020-01)Maize is an important staple crop for the majority of the population in Uganda. However, in tropical and subtropical climates, maize is frequently contaminated with aflatoxins, a group of cancer-causing and immuno-suppressive mycotoxins produced by Aspergillus section Flavi fungi. In Uganda, there is limited knowledge about the causal agents of aflatoxin contamination. The current study determined both the aflatoxin levels in pre-harvest maize across Uganda and the structures of communities of ... -
Genetic diversity of Ethiopian cowpea [Vigna unguiculata (L) Walp] genotypes using multivariate analyses
(2019)Cowpea is a multipurpose pulse crop grown by poor farmers in marginal and drought prone areas of Ethiopia. Information on the extent of genetic variation in cowpea genotypes is crucial to identify diverse genotypes for crop improvement and for efficient utilization of the existing genetic resources. Therefore, the objectives of the study were to assess the extent and pattern of morphological diversity among cowpea genotypes and to identify the traits contributing to the genetic diversity using ... -
Genetic improvement in resistance to Striga in tropical maize hybrids
(2019-11)Striga hermonthica (Del.) Benth parasitizes maize (Zea mays L.) in sub‐Saharan Africa, causing yield losses of up to 100% under severe infestation. Hybrid maize breeding for polygenic resistance to Striga has been undertaken at the International Institute of Tropical Agriculture (IITA) since the 1980s. This study was conducted to estimate genetic gain in grain yield and associated traits in a set of 32 maize hybrids developed over three breeding periods under artificial Striga ‐infested and ... -
Potential of inoculant and phosphorus application on soybean production in Mozambique
(2018-02)Inoculation with effective Bradyrhizobium spp., and phosphorus application enhance atmospheric nitrogen fixation in soybean production. Soybean form symbiotic associations with the right rhizobium strain to incorporate atmospheric nitrogen into the plant tissues. The objective of this study was to evaluate responses of two soybean varieties to inoculation, phosphorus and starter-nitrogen, and their interactions on nodulation, growth, yield components and grain yield in different agroecologies of ... -
Genetic diversity of South African sweetpotato germplasm using molecular markers
(2019)Sweetpotato (Ipomoea batatas L.(LAM)) is one of the most important food crops in developing countries, including South Africa. Most sweetpotato varieties in South Africa are cream or white fleshed and lack the essential beta-carotene of the orange-fleshed varieties. To develop new varieties with high beta-carotene, knowledge of the genetic variation of the crop is needed. The objectives of this study were to assess the genetic relationships among 30 orange- and cream-fleshed sweetpotato accessions ... -
Nutrient and antinutrient composition of winged bean (Psophocarpus tetragonolobus (L.) DC.) seeds and tubers
(2019)Many people in sub-Saharan Africa suffer from protein malnutrition; this results in negative health and economic impacts. Winged bean (Psophocarpus tetragonolobus (L.) DC.) is a tropical underutilized legume with beneficial nutritional characteristics such as high protein content, which may help to alleviate these problems. The proximate composition (fat, moisture content, crude protein, ash, and carbohydrate) and antinutrient (tannin and phytate) level of winged bean seeds and tubers were determined ... -
Phenotypic characterization of maize landraces from Sahel and Coastal West Africa reveals marked diversity and potential for genetic improvement.
(2019)Landraces of maize (Zea mays L.) are invaluable sources of genetic variability for improving agronomic traits, and they hold great promise in developing new maize varieties with enhanced resilience to stresses. Even though phenotypic characterization is an inexpensive approach for elucidating variation hidden in genetic resources, information on the genetic diversity patterns in large collections of landraces remains limited and this constitutes a major impediment for their optimal utilization in ... -
The role of women in production and management of RTB crops in Rwanda and Burundi: Do men decide, and women work?.
(2019)This paper evaluates the determinants of decision-making in relation to the production of four crops (banana, cassava, potato, and sweet potato). Understanding the division of labor and decision-making in crop management may lead to designing better interventions targeted at improving efficiency in smallholder agriculture. In 2014, the research team conducted a quantitative household survey with heads of households involving 261 women and 144 men in Burundi and 184 women and 222 men in Rwanda. ... -
Assessment of metabolic variability and diversity present in leaf, peel and pulp tissue of diploid and triploid Musa spp.
(2020-08)Banana (Musa spp.) plants produce many health promoting compounds in leaf, peel and pulp. For a robust metabolic analysis of these tissues, leaf at five developmental stages were compared to assess suitable sampling practices. Results confirmed that the common sampling practise of leaf 3 is applicable for metabolic comparisons. The developed work flow was applied to analyse the metabolite diversity present in 18 different Musa varieties, providing baseline levels of metabolites in leaf, peel and ...