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Journal and Journal Articles: Recent submissions
Now showing items 281-300 of 5266
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Assessment of the impact of crop management strategies on the yield of early-maturing maize varieties in the drylands of Niger Republic: Application of the DSSAT-CERES-Maize model
(2023-07-04)Maize is increasingly becoming important in Niger for use as food and feed. Production is however, faced with several abiotic and biotic constraints. Researchers have developed early-maturing maize varieties that are tolerant to drought, the parasitic weed Striga hermonthica and diseases that fit into the short growing production environment. The evaluation and deployment of these varieties would, however, involve costly and time-consuming field trials across the maize production zones of the ... -
Preparing for, coping with and bouncing back after shocks. A nuanced resilience assessment for smallholder farms and farmers in Northern Ghana
(2023)Smallholder farmers in Northern Ghana regularly face shocks, challenging the sustainability of their farms and livelihoods. Different farm households and household members may be differently affected and respond with different coping strategies. We combined whole-farm modelling and farmer consultations to investigate the vulnerability, buffer and adaptive capacity of three farm types in Northern Ghana towards severe climate, economic and social shocks. We further assessed intrahousehold differences ... -
Bias correction and spatial disaggregation of satellite-based data for the detection of rainfall seasonality indices
(2023-06-22)Like many other African countries, Ghana’s rain gauge networks are rapidly deteriorating, making it challenging to obtain real-time rainfall estimates. In recent years, real-time satellite precipitation products (SPPs) development and accessibility have advanced significantly. SPPs may compliment or substitute gauge data, enabling better real-time forecasting of streamflows among other things. SPPs, on the other hand, contain considerable biases that must be addressed before the rainfall predictions ... -
Bioinoculants and organic soil amendments affect nematode diversity in apple orchards
(2023-10)Nematodes with their versatile lifestyles provide a suitable lens to decipher the conditions of agroecosystems, but less is known about how they are affected by bioinoculants and organic soil amendments. To test if treatments modify the nematode community, we studied nematode communities in two different apple orchards under organic and integrated farming. Soil was treated with products containing arbuscular mycorrhizal fungi, bioeffectors, and organic amendments. The comparison between baseline ... -
Managing fall armyworm (Spodoptera frugiperda J.E. Smith) using leaf residue of neem (Azadirachta indica A. Juss) on maize (Zea mays L.) under natural infestation
(2023-06-01)Fall armyworm (Spodoptera frugiperda J.E. Smith) is a pest that has established across sub-Saharan Africa, capable of causing 100% yield loss in maize. Although aqueous extracts of neem (Azadirachta indica A. Juss) are being used to manage this pest, neem leaf residue may have added beneficial effects. This investigation was conducted during April–November 2020 at the Training and Research Farm, University of Benin, Nigeria, aiming to improve maize yields by using neem leaf residue for managing ... -
Endophytic fungi improve management of the burrowing nematode in banana (Musa spp.) through enhanced expression of defence-related genes
(2023-03-02)The root-burrowing nematode, Radopholus similis, is reputedly the most damaging nematode pest of banana and responsible for major production losses. In this study, the endophytic potential of 13 fungal isolates was assessed for the management of R. similis in East African Highland bananas (‘Ng’ombe’). All isolates successfully colonised tissue-cultured banana roots, with isolates from Trichoderma, Fusarium and Hypocrea producing the highest (⩾49.1%) and Beauveria isolates the lowest (⩽14.4%) ... -
Biocontrol-based strategies for improving soil health and managing plant-parasitic nematodes in coffee production
(2023-06-20)Coffee is an important commodity for Kenya, where production is steadily declining, despite a global rise in demand. Of the various constraints affecting production, plant-parasitic nematodes are a significant, but often overlooked, threat. As a perennial crop, treating plantations once infected with nematodes becomes difficult. The current study evaluated the drenching application of two biocontrol agents, Trichoderma asperellum and Purpureocillium lilacinum, for their nematode control efficacy, ... -
Drivers of maize yield variability at household level in northern Ghana and Malawi
(2023-07-03)Maize is a staple food, but productivity has stagnated due to limited access to advanced farming methods and knowledge. To promote sustainable agriculture, understanding the factors affecting maize yield at the farm level is crucial. This study used panel data on maize yield and agronomic practices in Northern Ghana and Malawi from 2014 to 2020. Satellite-based environmental variables were extracted at household locations, and Random Forest modeling was used to identify factors influencing maize ... -
Closing the yield gap of soybean (Glycine max (L.) Merril) in southern Africa: a case of Malawi, Zambia, and Mozambique.
(2023-07-07)Introduction: Smallholder farmers in Sub-Saharan Africa (SSA) are increasingly producing soybean for food, feed, cash, and soil fertility improvement. Yet, the difference between the smallholder farmers’ yield and either the attainable in research fields or the potential from crop models is wide. Reasons for the yield gap include low to nonapplication of appropriate fertilizers and inoculants, late planting, low plant populations, recycling seeds, etc. Methods: Here, we reviewed the literature on ... -
Modelling the impacts of diverse cover crops on soil water and nitrogen and cash crop yields in a sub-tropical dryland
(2023-10-01)Understanding the implications of replacing fallows with cover crops on plant-available water (PAW) and soil mineral nitrogen (N) and their carry-over effects on subsequent cash crops is critical for understanding their potential for ecological intensification in water-limited environments. We modelled the impacts of different cover crop functional types over historical climate to predict how climate variability influences soil water and N acquisition and subsequent availability to a maize crop ... -
Analysis of population structure and genetic diversity in a Southern African soybean collection based on single nucleotide polymorphism markers
(2023)Soybean is an emerging strategic crop for nutrition, food security, and livestock feed in Africa, but improvement of its productivity is hampered by low genetic diversity. There is need for broadening the tropical germplasm base through incorporation and introgression of temperate germplasm in Southern Africa breeding programs. Therefore, this study was conducted to determine the population structure and molecular diversity among 180 temperate and 30 tropical soybean accessions using single ... -
Combining manure with mineral N fertilizer maintains maize yields: evidence from four long-term experiments in Kenya
(2023-02-01)Context Crop productivity in sub-Saharan Africa cannot be substantially improved without simultaneously addressing short-term crop nutrient demand and long-term soil fertility. Integrated soil fertility management tackles both by the combined application of mineral fertilizers and organic resource inputs but few studies examined its‘ long-term effectiveness. Objective To address this knowledge gap, this study analysed maize yield trends in four long-term (31–37 cropping seasons) field experiments ... -
Performance evaluation of available strains of Nile tilapia (Oreochromis niloticus) fed commercial and locally-made feeds in the Democratic Republic of the Congo
(2023)The performance of two strains of Nile tilapia (the Nyakabera and Lake Kivu) fed a commercial feed or either a fishmeal-based or a fishmeal-free feed formulated using local ingredients was evaluated for 99 days in Bukavu, eastern highlands of the DR Congo (Experiment 1). Strain × feed interaction was significant (p < 0.05) for final body weight (FBW) and condition factor (CF). Growth of both strains was best with the commercial feed. Fish-meal free formulated feed resulted in similar or better ... -
Reduction of P fertilizer requirement using lime and Mucuna on high P-sorption soils of NW Cameroon.
(1996)Soil acidity and high phosphorus (P) fixation are real problems in the Highlands of Central and Eastern Africa. Phosphatic fertilizers are imported and costly for the average farmer. We used lime and Mucuna green manure to reduce fertilizer P requirement of traditional food crops in NW Camcroon. Lime and phosphorus significantly improved stand count, root and stem weights as well as yields of maize (Zea mays L.), bean (Phaseolus spp.), and Irish potato (Solanum tuberosum L.) in three consecutive ... -
Fertility characterization of soils at six research sites in NW Cameroon
(1995-01)Fertility capability of surface (0–20 cm) soils was evaluated at six sites in the North-West Cameroon highlands. Two main soil groups, designated as Classes A and B, were identified based on elevation. The Class A soils from low elevations (600–1178 m) had higher Ca, Mg, K, pH, sorbed less P and were lower in organic carbon and sesquioxides than the highland (> 1200 m) soils. Soil acidity (Al saturation > 30%) and high P sorption appeared to be the most limiting factors to crop production especially ... -
Connecting data for consumer preferences, food quality, and breeding in support of market-oriented breeding of root, tuber, and banana crops
(2023)The 5-year project ‘Breeding roots, tubers and banana products for end user preferences’ (RTBfoods) focused on collecting consumers' preferences on 12 food products to guide breeding programmes. It involved multidisciplinary teams from Africa, Latin America, and Europe. Diverse data types were generated on preferred qualities of users (farmers, family and entrepreneurial processors, traders or retailers, and consumers). Country-based target product profiles were produced with a comprehensive market ... -
Implication of blanket NPK application on nutrient balance of maize based on soil and tissue diagnosis approaches in the savannas of northern Nigeria
(2023)Improper nutrient management reduces the yield and affects the nutrient status of crops. This study aimed to diagnose the nutrients limitation in maize. A three-year multi-location (348 sites) nutrient experiments were conducted in randomized block design to analyse nutrients limitation for maize production under conventional fertilizer recommendation system in Nigeria using DRIS, and to identify soil factors that influence DRIS indices using random forest model. DRIS indices for nutrients were ... -
Do soil and water conservation practices influence crop productivity and household welfare? Evidence from rural Nigeria
(2023-04)One of the most serious challenges threatening agricultural sustainability in Nigeria is land degradation. Although this issue has received little attention, soil and water conservation practices have been identified as a possible pathway out of the potential problems posed by land degradation. Therefore, the central research question that this paper tries to address is the following: Do adoption of soil and water conservation (SWC) practices affect crop productivity and household welfare? This ... -
Prediction of functional characteristics of gari (cassava flakes) using near-infrared reflectance spectrometry
(2023-05-10)Gari is a creamy, granular flour obtained from roasting fermented cassava mash. Its preparation involves several unit operations, including fermentation, which is essential in gari production. Fermentation brings about specific biochemical changes in cassava starch due to the actions of lactic acid bacteria. Consequently, it gives rise to organic acids and a significant reduction in the pH. Consumer preferences for gari are influenced by these changes and impact specific functional characteristics, ... -
Elite cassava clones (Manihot esculenta) grown in Zambia: effects of drying techniques on their chemical, functional, and pasting properties.
(2023)Introduction: Cassava (Manihot esculanta) is becoming an important crop in most developing countries, especially Zambia. However, cassava roots deteriorate quickly after harvest, producing flour or chips of sub-optimal quality. Hence the evaluation of processing procedures to extend the product’s shelf-life cannot be overemphasized. This study investigated the effects of different drying methods on the chemical, functional and pasting properties of selected advanced cassava clones grown in Zambia. ...