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Journal and Journal Articles: Recent submissions
Now showing items 301-320 of 5266
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Genetic mapping, candidate gene identification and marker validation for host plant resistance to the race 4 of Fusarium oxysporum f. sp. cubense using Musa acuminata ssp. malaccensis
(2023-06)Fusarium wilt of banana is a devastating disease that has decimated banana production worldwide. Host resistance to Fusarium oxysporum f. sp. Cubense (Foc), the causal agent of this disease, is genetically dissected in this study using two Musa acuminata ssp. Malaccensis segregating populations, segregating for Foc Tropical (TR4) and Subtropical (STR4) race 4 resistance. Marker loci and trait association using 11 SNP-based PCR markers allowed the candidate region to be delimited to a 12.9 cM genetic ... -
A report of meloidogyne arenaria parasitizing plantain (Musa spp., AAB) in Nigeria
(2023-06-06)Extensive root galling observed on plantain (Musa spp., AAB) in Nigeria was analysed using Nad5 mitochondrial DNA sequences and the causal agent identified as Meloidogyne arenaria. Following the inoculation of population cultured, Koch’s postulates was fulfilled and the same symptoms observed. This provides the first molecular confirmation of M. arenaria causing such damage to plantain and highlighting its potential as a threat to the crop. Root knot nematodes are known to affect banana and plantain ... -
Managing soil organic carbon in tropical agroecosystems: evidence from four long-term experiments in Kenya
(2023-06-05)In sub-Saharan Africa, maize is one of the most important staple crops, but long-term maize cropping with low external inputs has been associated with the loss of soil fertility. While adding high-quality organic resources combined with mineral fertilizer has been proposed to counteract this fertility loss, the long-term effectiveness and interactions with site properties still require more understanding. This study used repeated measurements over time to assess the effect of different quantities ... -
Increased mineral fertilizer use on maize can improve both household food security and regional food production in East Africa
(2023-02)CONTEXT Despite recent improvements in living standards, a substantial proportion of farm households in sub-Saharan Africa (SSA) is food insecure, and increasing crop productivity could help address this problem. OBJECTIVE We estimated the effect of increasing maize yields with mineral fertilizer on household food security and on regional and national maize supply in two East African countries - Uganda and Tanzania. METHODS We estimated maize yield response to nitrogen (N) fertilization ... -
Maturity class and P effects on soya bean grain yield in the moist Savanna of west Africa
(2003-12)Field trials were replicated at four sites in the moist savanna ecological zone of West Africa to study the effect of maturity class and phosphorus (P) rate on grain yield and total protein yield (TPY) of some new soya bean varieties. Grain yield and TPY averaged 1.43 Mg ha−1 and 587 kg ha−1, respectively. Without P application grain yield and TPY were not significantly different among the varieties. In addition, at zero P treatment, grain yield and TPY were not significantly different among three ... -
Consistency, variability, and predictability of on-farm nutrient responses in four grain legumes across east and west Africa
(2023-08)Grain legumes are key components of sustainable production systems in sub-Saharan Africa, but wide-spread nutrient deficiencies severely restrict yields. Whereas legumes can meet a large part of their nitrogen (N) requirement through symbiosis with N2-fixing bacteria, elements such as phosphorus (P), potassium (K) and secondary and micronutrients may still be limiting and require supplementation. Responses to P are generally strong but variable, while evidence for other nutrients tends to show ... -
The role of inter-specific competition for water in maize-legume intercropping systems in northern Tanzania
(2023-04)CONTEXT Maize-legume intercropping is common in sub-Saharan Africa. Effects of legumes on the companion maize crop are determined principally by choice of legume species and relative introduction time. Performance of intercrops is optimized when legumes' planting is timed such that their peak growth phase occurs after maize harvest, with legumes utilizing the residual soil moisture. OBJECTIVE We sought to understand the role of inter-specific competition for water in maize-pigeonpea and maize-lablab ... -
Soil mineralogical and nutrient characteristics of forest islands and surrounding ecosystem types in West Africa suggest anthropogenic soil improvement
(2023-05-12)Aims Ecosystem changes in the mesic savannas of West Africa are resulting in the formation of patches of ‘forest islands’ around local communities in an otherwise open savanna landscape. There have been conflicting reports on the origin of these forest islands with a very limited understanding of their biogeochemistry. This study evaluated the soil mineralogical and chemical characteristics of forest islands and their surrounding ecosystems comprising croplands and open savannas in Burkina Faso, ... -
Evaluation of training on good agronomic practices for seed yam production in Nigeria
(2023-02-28)The second phase of the Yam Improvement for Income and Food Security in West Africa (YIIFSWA II) project was implemented through a strong collaboration between research and private sector. Private seed companies were provided with a wide variety of training and development activities on good agronomic practices (GAPs). However, the effects of the training activities were yet to be evaluated. This paper evaluated the contribution of the training on high-quality seed yam production through paying ... -
What future for banana-based farming systems in Uganda? A participatory scenario analysis
(2023-06)CONTEXT: Population pressure, land scarcity and encroachment of nature reserves are challenging sustainable intensification of agriculture in Uganda. One of the main staple crops in Uganda is East African Highland banana. Area expansion and improved management have enhanced the economic performance of banana, yet at the expense of food security, environmental and social sustainability. While a transition of banana-based farming systems to a more sustainable future seems necessary, the desired ... -
Can young agripreneurs improve their skills through agripreneurship empowerment programmes? Evidence from Africa
(2023-01-07)This article examined the driving forces behind young agripreneurs’ participation in agripreneurship empowerment programmes and estimates the causal impact of programme participation on agripreneurship skills using data from a random cross-section sample of 1435 young agripreneurs in Kenya, Nigeria, and Uganda. Specifically, the study took evidence from the youth component of the African Development Bank Technologies for African Agricultural Transformation (TAAT) programme, Empowering Novel ... -
Assessing food security among young farmers in Africa: evidence from Kenya, Nigeria, and Uganda
(2023-02-23)Food insecurity remains a serious challenge for many households in Africa and the situation is even more prevalent among young people. However, there is a dearth of empirical evidence on youth food security status in Africa. We assessed the level and determinants of food security among young farmers in Africa. We adopted a multi-stage sampling technique to select 400, 429, and 606 young farmers in Kenya, Nigeria, and Uganda, respectively. Individual food consumption was assessed following a 7 days ... -
Evaluating combined effects of pesticide and crop nutrition (with N, P, K and Si) on weevil damage in east African highland bananas
(2023-03-10)Banana weevil (Cosmopolites sordidus, Germar) is a major pest in East African Highland Banana. The influence of crop nutritional status on weevil damage is poorly understood. Nutrient availability affects the nutritional quality of plants for weevils and may affect weevil damage. Here, we evaluate the effect of insecticides alone and in combination with fertilisers (N, P, K and Si) on weevil damage using data from two experiments in central and southwest Uganda. In the first experiment, we varied ... -
Impact of informal institutions on youth agribusiness participation in southern Benin
(2023-03-28)The agribusiness sector development is often portrayed as an essential component of economic development. Though Benin is a country with inestimable agricultural potential, the agribusiness sector appears unappealing to the local youths. Prior investigations diagnosed the impeding factors as a paucity of financial resource and a dearth of land and technical knowledge. This article departs from past studies by considering the importance of informal institutions for youth participation in the ... -
Breeding cowpea for adaptation to intercropping for sustainable intensification in the Guinea Savannas of Nigeria
(2023-01)Cowpea is a multifaceted crop; however, considerable challenges affect the production of this crop despite its comparatively better adaptation to harsh environments. Most smallholder farmers in West Africa cultivate this crop in intercropping systems where its low plant population does not allow the full expression of the cultivars’ yield potential. This is because most varieties currently grown in intercrop have been developed in and for monocropping, although some breeding programs recently have ... -
Climate change challenges, plant science solutions
(2023-01)Climate change is a defining challenge of the 21st century, and this decade is a critical time for action to mitigate the worst effects on human populations and ecosystems. Plant science can play an important role in developing crops with enhanced resilience to harsh conditions (e.g. heat, drought, salt stress, flooding, disease outbreaks) and engineering efficient carbon-capturing and carbon-sequestering plants. Here, we present examples of research being conducted in these areas and discuss ... -
Evaluating phloem sap δ13C as a short-term indicator of drought stress in banana
(2023-05)Water shortage is the most important abiotic limitation for banana. The development of climate-smart cultivars and agronomic practices is ongoing, but the process is hindered by a lack of field-applicable drought stress evaluation methods. Earlier research indicated that carbon isotope discrimination values in bulk leaf material (δ13Cbulk) could serve as a proxy for drought stress in banana. However, δ13Cbulk is a time-integrated measure of stress. Information about current and short-term conditions ... -
Exploring nitrogen use efficiency in Musa spp.
(2023-05)Banana (Musa spp.) is an important staple crop, especially in developing countries where it ensures food security. However, optimal yields are not obtained due to both biotic and abiotic constraints. Low soil fertility is one of the limiting factors in the East African highlands, as the currently applied amount of organic (crop residues, animal manure, etc.) and inorganic fertilizers by smallholder farmers is not sufficient to maintain adequate soil fertility levels for optimal growth and production. ... -
Explaining the positioning of agricultural entrepreneurs on the necessity-opportunity continuum in sub-Saharan Africa: insights from Benin
(2023-05)Despite the potential of agriculture to reduce unemployment in sub-Saharan Africa, research on agricultural entrepreneurship is scarce, especially regarding the entrepreneurs’ motivations. The aim of this research is to examine the intensity of necessity and opportunity motivations among agricultural entrepreneurs and the influence of socioeconomic characteristics, personality, and environmental factors. Hence, the study reports a survey of 819 agricultural entrepreneurs in Benin and uses multinomial ...