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Unveiling African rainforest composition and vulnerability to global change
(2021)Africa is forecasted to experience large and rapid climate change1 and population growth2 during the twenty-first century, which threatens the world’s second largest rainforest. Protecting and sustainably managing these African forests requires an increased understanding of their compositional heterogeneity, the environmental drivers of forest composition and their vulnerability to ongoing changes. Here, using a very large dataset of 6 million trees in more than 180,000 field plots, we jointly ... -
Effect of single or dual inoculation of the arbuscular mycorrhizal fungus Glomus mosseae and root‑nodulating rhizobacteria on reproduction of the burrowing nematode Radopholus similis on non‑leguminous and leguminous banana intercrops
(2021)The bio-protective effect of either single or dual mycorrhizal (AMF) and rhizobial colonisation of the roots of non-leguminous and leguminous banana intercrops differing in host response to Radopholus similis on the reproduction of this important migratory endoparasitic nematode was examined. Included in the study were sorgho-Sudan grass (good R. similis host), sweet potato and common bean (intermediate hosts), soybean and sunn hemp (poor hosts), and marigold (non-host). Significant plant ... -
Direct estimation of maize leaf area index as influenced by organic and inorganic fertilizer rates in Guinea Savanna
(2020-05-15)Leaf area index (LAI) plays an important role in radiation capture, crop growth and yield formation. However, there is limited quantitative data on the influence of poultry manure (PM) and NPK fertilizer rate (NPK) on LAI, as estimated directly. Using a split-plot design with three replications, a field experiment was conducted to determine the effects of three PM rate (0, 2 and 4 t/ha) as main plot and three NPK rate (0:0:0, 60:30:30 and 120:60:60 kg N P2O5 K2O/ha) as sub plot, on LAI and maize ... -
Simulating the response of drought-tolerant maize varieties to nitrogen application in contrasting environments in the Nigeria Savannas using the APSIM Model
(2020-12-31)This paper assessed the application of the Agricultural Production Systems sIMulator (APSIM)–maize module as a decision support tool for optimizing nitrogen application to determine yield and net return of maize production under current agricultural practices in the Nigeria savannas. The model was calibrated for two maize varieties using data from field experiments conducted under optimum conditions in three locations during the 2017 and 2018 cropping seasons. The model was evaluated using an ... -
Optimizing sowing density-based management decisions with different nitrogen rates on smallholder maize farms in northern Nigeria
(2021)In this study, the CERES-Maize model was calibrated and evaluated using data from 60 farmers’ fields across Sudan (SS) and Northern Guinea (NGS) Savannas of Nigeria in 2016 and 2017 rainy seasons. The trials consisted of 10 maize varieties sown at three different sowing densities (2.6, 5.3, and 6.6 plants m−2) across farmers’ field with contrasting agronomic and nutrient management histories. Model predictions in both years and locations were close to observed data for both calibration and evaluation ... -
Introducing a mechanistic model in digital soil mapping to predict soil organic matter stocks in the Cantabrian region (Spain)
(2021-03)Digital soil mapping (DSM) is an effective mapping technique that supports the increased need for quantitative soil data. In DSM, soil properties are correlated with environmental characteristics using statistical models such as regression. However, many of these relationships are explicitly described in mechanistic simulation models. Therefore, the mechanistic relationships can, in theory, replace the statistical relationships in DSM. This study aims to develop a mechanistic model to predict soil ... -
Comparative transcriptome and expression profiling of resistant and susceptible banana cultivars during infection by Fusarium oxysporum
(2021)Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc) is one of the most destructive diseases of banana. Methods to control the disease are still inadequate. The present investigation targeted expression of defense-related genes in tissue cultured banana plantlets of Fusarium resistant and susceptible cultivars after infection with biological control agents (BCAs) and Fusarium (Foc race 1). In total 3034 differentially expressed genes were identified which annotated to 58 transcriptional ... -
Global habitat suitability of Spodoptera frugiperda (JE Smith) (Lepidoptera, Noctuidae): key parasitoids considered for its biological control
(2021)The present study is the first modeling effort at a global scale to predict habitat suitability of fall armyworm (FAW), Spodoptera frugiperda and its key parasitoids, namely Chelonus insularis, Cotesia marginiventris,Eiphosoma laphygmae,Telenomus remus and Trichogramma pretiosum, to be considered for biological control. An adjusted procedure of a machine-learning algorithm, the maximum entropy (Maxent), was applied for the modeling experiments. Model predictions showed particularly high establishment ... -
Detection of non-additive gene action within elite maize populations evaluated in contrasting environments under rainforest ecology in Nigeria
(2021)Proper understanding of the mode of gene action in open-pollinated varieties (OPVs) maize parents helps breeder in the choice of appropriate breeding method to improve its genetic value. The objectives of the present study were to determine gene action controlling grain yield and other agronomic traits of late maturing elite OPVs and classify the varieties into heterotic groups. Ninety-one hybrids generated from 14 elite OPV parents using diallel mating design were evaluated with their parents ... -
Factors influencing implementation of bylaws on sustainable crop intensification: evidence from potatoes in southwestern Uganda
(2020)The study examined the factors for the successful implementation of bylaws on sustainable crop intensification. The study used the new institutionalism theory to examine the implementation of bylaws in the potato cropping system in southwestern Uganda. A mixed model featuring both qualitative and quantitative approaches was used in the study. This involved analysis of primary data. The primary sources were key informants, focus group discussions, and face to face interviews with individual farmers, ... -
From cassava to gari: mapping of quality characteristics and end-user preferences in Cameroon and Nigeria
(2021)User’s preferences of cassava and cassava products along the value chain are supported by specific root quality characteristics that can be linked to root traits. Therefore, providing an evidence base of user preferred characteristics along the value chain can help in the functional choice of cassava varieties. In this respect, the present paper presents the results from focus group discussions and individual interviews on user preferred quality characteristics of raw cassava roots and the derived ... -
Cocoa marketing chain in developing countries: how do formal-informal linkages ensure its sustainability in Cameroon?
(2020-12)Although liberalization of the cocoa sector has increased internal competition within the marketing chain it has also led to the emergence of informal market actors within the chain. Therefore, the aim of this paper is to analyse how the cocoa marketing chain operates by measuring and comparing the marketing margins of the formal and informal actors. Qualitative data were used to establish the structure of the marketing chain and quantitative data to estimate the marketing margins. A total sampling ... -
Evaluating animal-based foods and plant-based alternatives using multi-criteria and SWOT analyses
(2020)Global diets have transitioned in recent decades with animal and processed products increasing. Promoting a reversal in these trends towards plant-based diets could reduce the environmental impacts of food systems and reduce the prevalence of non-communicable diseases and malnutrition. In Spain, a reference point for the Mediterranean diet (predominantly plant-source based), plant-based alternatives to traditional animal-based products are receiving increased attention. However, limited focus has ... -
Understanding cassava varietal preferences through pairwise ranking of gari-eba and fufu prepared by local farmer-processors
(2021)Within communities in Osun and Imo States of Nigeria, farmer–processors grew and processed a diverse set of improved and landrace cassava varieties into the locally popular foods, gari, eba and fufu. Local and 15 main varieties were grown in a ‘mother and baby trials’ design in each state. Mother trials with three replications were processed by farmer–processors renown in their community for their processing skills. Baby trials were managed and processed by other farmer–processors. The objective ... -
Comparing the functional and pasting properties of gari and the sensory attributes of the eba produced using backslopped and spontaneous fermentation methods
(2021)The possibilities of backslopped fermentation replacing spontaneous fermentation in gari production were evaluated by comparing the functional and pasting properties of gari and the sensory attributes of the eba. Backslopped cassava mash (BCM) was produced from 75 kg of TMS13F1343 cassava roots by pre-fermenting for 96 h. The BCM was mixed with fresh cassava mash (FCM) from another 75 kg of the same variety using design expert software developed blend ratios and processed to backslopped fermented ... -
Leaf traits variation of arabica coffee cultivars in response to population density and mineral nutrient
(2020-12-30)Leaf trait is good predictors of plant performance. It is closely associated with light requirement, growth and survival of the plant. This study was designed to evaluate the effect of seedling planting density and fertilizer rate on leaf traits variation of two Arabica coffee cultivars under nursery conditions. It was conducted at Jimma Agricultural Research Center from (February 29 to October 29), 2018. A factorial experiment was used and treatments were arranged using completely randomized ... -
Low soil nutrient tolerance and mineral fertilizer response in White Guinea Yam (Dioscorea rotundata) genotypes
(2021)Yam (Dioscorea spp.) is a major food security crop for millions of resource-poor farmers, particularly in West Africa. Soil mineral deficiency is the main challenge in yam production, especially with the dwindling of fallow lands for the indigenous nutrient supply. Cultivars tolerant to available low soil nutrients and responsive to added nutrient supply are viable components of an integrated soil fertility management strategy for sustainable and productive yam farming systems in West Africa. This ... -
Gender roles in sourcing and sharing of banana planting material in communities with and without banana bunchy top disease in Nigeria
(2021)Banana bunchy top disease (BBTD) is the most devastating disease of banana and plantain (Musa spp.). The disease spreads through the use of infected vegetative propagules and the banana aphid (Pentalonia nigronervosa) is the virus vector. This study seeks to understand the gender dimensions and sociocultural aspects of banana seed (vegetative propagule) sourcing and sharing practices among men and women farmers, and its influence on BBTD spread and disease control efforts. Data were collected from ... -
Genetic parameter estimation and selection in advanced breeding population of white Guinea yam
(2021)White Guinea yam (Dioscorea rotundata Poir.) is an important tuber crop grown extensively in tropical regions of West African yam belt. Tuber yield, dry matter content, and tolerance to yam mosaic virus are key traits used for identification and selection of superior varieties for commercial deployment. In this study, we estimated genetic parameters for fresh tuber yield, tuber dry matter content, and quantitative field tolerance to yam mosaic virus in 49 clones grown in multi-environment trials ... -
Auxin signaling and vascular cambium formation enables storage metabolism in cassava tuberous roots
(2021)Cassava storage roots are among the most important root crops worldwide and represent one of the most consumed staple foods in Sub-Saharan Africa. The vegetatively propagated tropical shrub can form many starchy tuberous roots from its stem. These storage roots are formed through the activation of secondary root growth processes. However, the underlying genetic regulation of storage root development is largely unknown. Here we report on distinct structural and transcriptional changes occurring ...
