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Journal and Journal Articles: Recent submissions
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Using farm typology to understand banana Xanthomonas wilt management in Rwanda
(2024-01-09)This study aims to contribute to the understanding of diversity within the context of banana farming and its implications for the management of banana Xanthomonas wilt (BXW) disease in Rwanda. We used a structured questionnaire to collect data from 690 banana farmers in eight districts, representing various agroecological zones, across Rwanda. We implemented principal component analysis (PCA) and hierarchical cluster analysis (HCA) of the data leading to the delineation of three distinct groups ... -
Combining temperature-dependent life table data into Insect Life Cycle Model to forecast fall armyworm Spodoptera frugiperda (JE Smith) distribution in maize agro-ecological zones in Africa
(2024-05-06)The fall armyworm (FAW), Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), an invasive agricultural pest, has significantly impacted crop yields across Africa. This study investigated the relationship between temperature and FAW life history traits, employing life cycle modeling at temperatures of 20, 25, 28, 30, and 32°C. The development time for eggs, larvae, and pupae varied from 0–3 days, 10–18 days, and 7–16 days, respectively. The optimal temperature range for immature stage survival ... -
Stability analysis and nutritional quality of soybean (Glycine max (L).Merrill.) genotypes for feed in southwestern Ethiopia
(2024-04-15)Soybean is a leguminous crop known for its multiple utilizations both as food and feed for humans and livestock. The objectives of the study were to identify high dry matter yielder and stable genotypes across environments in southwestern Ethiopia. The effect of genotype environment (G x E) interaction on dry matter yield of soybean genotypes were evaluated in two cropping seasons (2019–2020) under rain fed condition. Eight pre tested soybean genotypes with two checks were used as treatment in a ... -
Variation among cassava (Manihot esculenta Crantz) genotypes for storage root yield, yield components and response to cassava mosaic disease at the advanced breeding stage
(2024-06-19)Cassava is a crucial starchy root crop cultivated worldwide in tropical and subtropical areas. Efforts have been made to improve its desirable characteristics to increase food and nutritional quality. However, the adoption of new cassava varieties can be influenced by their yield performance, which can be affected by cassava mosaic disease (CMD). The present study evaluated selected cassava genotypes' performance across two years at the advanced breeding stage. Using a randomized complete block ... -
Variations in micronutrient concentrations and retentions in fufu made from yellow-fleshed cassava as a function of genotype and processing methods
(2024-05-22)Introduction The biofortification of staple foods such as cassava is one of the technological breakthroughs in the nutritional improvement of foods. Fufu is one of the fermented cassava products produced and consumed in major West African countries, including Sierra Leone, and the majority of the processes involved in its production have direct and indirect effects on its properties. This study looked at how the concentration and retention of micronutrients in yellow-fleshed cassava fufu varied ... -
Strategic Foresight analysis of droughts in southern Africa and implications for food security
(2024-02-14)Southern Africa has been experiencing long-term changes in its climate and future projections imply that droughts should last longer and become more intense in southern Africa. Already, the region has been experiencing an increase in consecutive drought years. This study contributes to the literature by using bio-economic modeling to simulate the impact of future droughts on food security in southern Africa and identify plausible pathways for enhancing regional food security under drought. Food ... -
Combining temperature-dependent life table data into Insect Life Cycle Model to forecast fall armyworm Spodoptera frugiperda (JE Smith) distribution in maize agro-ecological zones in Africa
(2024-05-06)The fall armyworm (FAW), Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), an invasive agricultural pest, has significantly impacted crop yields across Africa. This study investigated the relationship between temperature and FAW life history traits, employing life cycle modeling at temperatures of 20, 25, 28, 30, and 32°C. The development time for eggs, larvae, and pupae varied from 0–3 days, 10–18 days, and 7–16 days, respectively. The optimal temperature range for immature stage survival ... -
Genome-wide association studies of photosynthetic and agronomic traits in cowpea collection
(2024-10-04)Exploring genomic regions linked with drought tolerance and photosynthesis in cowpea could accelerate breeding of climate-resilient cowpea varieties. A genome-wide association study (GWAS) was conducted to identify marker–trait associations for agronomic and photosynthetic traits measured under well-watered and water-stressed conditions. One hundred and twelve cowpea accessions from IITA were phenotyped for agronomic and photosynthetic traits across 3 locations in 2 years: Ibadan, Ikenne (2020 and ... -
Genome-wide association study for yield and quality of granulated cassava processed product
(2024-06-16)The starchy storage roots of cassava are commonly processed into a variety of products, including cassava granulated processed products (gari). The commercial value of cassava roots depends on the yield and quality of processed products, directly influencing the acceptance of new varieties by farmers, processors, and consumers. This study aims to estimate genetic advance through phenotypic selection and identify genomic regions associated and candidate genes linked with gari yield and quality. ... -
Assessment of climate change impact and adaptation strategy for millet in the Sudano‑Sahelian region of Niger
(2024-10-03)Pearl millet is an important food and fodder crop in West African semi-arid regions. Climate change is projected to have a significant impact on the productivity of the crops in these regions. Adaptation strategies to sustain agricultural production are therefore urgently required to sustain millet productivity. The Decision Support System for Agrotechnology Transfer (DSSAT) CERES-Millet model was used to assess the impact of climate change and adaptation strategies on millet in Niger. Three millet ... -
Adoption of agronomic practices and their impact on crop yield and income: an analysis for black gram and green gram in India
(2024)Black gram and green gram are important pulse crops in India, but their production has faced fluctuations and stagnancy in yields over the last few decades. The Government of India has implemented several measures to enhance crop yield, including recommending and promoting the adoption of crop-specific agronomic practices. However, there is limited empirical evidence on the determinants of the adoption of these practices and their impact on yield and income. In this context, this study analyses ... -
Weeding force saving to improve profitability of cassava-legumes cropping systems in eastern Democratic Republic of the Congo
(2025-01)Weeding is a common farming practice for optimal emergence, growth and maturity of crops. Smallholders in Central Africa use a traditional hoe for weed control. This is a hard and time-consuming activity. To address this bottleneck, a study was conducted at three sites, namely Walungu, Uvira, and Mulungu in South-Kivu in the Democratic Republic of the Congo (DRC), over two growing seasons (September 2020 and February 2021). The purpose was to minimize the workload involved in weed control and ... -
Willingness of West African consumers to buy food produced using black soldier fly larvae and frass
(2024-09-05)The use of black soldier fly (BSF) larvae and frass in agriculture can make an important contribution to food and nutrition security. However, it is important to understand whether consumers are willing to consume food products resulting from the use of BSF larvae as animal feed or BSF frass as fertilizer. This study employed the stated preference approach as food products produced using BSF larvae and frass are not currently available on the market. Questionnaires were administered to a total of ... -
A crop-specific and time-variant spatial framework to characterize production environments: a case study for rainfed wheat in Ethiopia
(2024-08-03)Abstract1. CONTEXTAddressing the limitations of scaling agronomic recommendations, which are usually confined to small areas, requires a spatial framework for characterizing production environments in a timely and cost-effective manner.2.OBJECTIVEThis study aimed to introduce a data-driven framework to characterize rainfed wheat crop production environments in Ethiopia. The framework entails mapping of the annual rainfed wheat area and the delineation of crop-specific and dynamic agro-ecological ... -
Assessment of climate change impact and adaptation strategy for millet in the Sudano‑Sahelian region of Niger
(2024-12)Pearl millet is an important food and fodder crop in West African semi-arid regions. Climate change is projected to have a significant impact on the productivity of the crops in these regions. Adaptation strategies to sustain agricultural production are therefore urgently required to sustain millet productivity. The Decision Support System for Agrotechnology Transfer (DSSAT) CERES-Millet model was used to assess the impact of climate change and adaptation strategies on millet in Niger. Three millet ... -
Combined use of improved maize hybrids and nitrogen application increases grain yield of maize, under natural Striga hermonthica infestation
(2024)Striga hermonthica (Del.) Benth infestation is one of the major constraints to maize production in the Nigeria savannas. The application of nitrogen fertilizer to Striga-resistant hybrids may reduce Striga infection and increase grain yields. The objective of this study was to assess the performance of six maize hybrids at low (30 kg ha−1) and high (120 kg ha−1) nitrogen application under natural infestation with Striga in northern Nigeria in 2014 and 2015. The two nitrogen rates and the six hybrids ... -
Combined use of improved maize hybrids and nitrogen application increases grain yield of maize, under natural Striga hermonthica infestation
(2024-10-04)Striga hermonthica (Del.) Benth infestation is one of the major constraints to maize production in the Nigeria savannas. The application of nitrogen fertilizer to Striga-resistant hybrids may reduce Striga infection and increase grain yields. The objective of this study was to assess the performance of six maize hybrids at low (30 kg ha−1) and high (120 kg ha−1) nitrogen application under natural infestation with Striga in northern Nigeria in 2014 and 2015. The two nitrogen rates and the six hybrids ... -
Genetic progress in cowpea [Vigna unguiculata (L.) Walp.] stemming from breeding modernization efforts at the International Institute of Tropical Agriculture
(2024-05-22)Genetic gain has been proposed as a quantifiable key performance indicator that can be used to monitor breeding programs’ effectiveness. The cowpea breeding program at the International Institute of Tropical Agriculture (IITA) has developed and released improved varieties in 70 countries globally. To quantify the genetic changes to grain yield and related traits, we exploited IITA cowpea historical multi environment trials (METs) advanced yield trial (AYT) data from 2010 to 2022. The genetic gain ... -
Shifting focus from external to in situ organic resources – The redesign of four tropical long-term experiments
(2024-04-30)Long-term experiments (LTEs) are critical for evaluating strategies that can maintain or increase crop yields, soil fertility and soil organic carbon (SOC), and help adapt to climate change. Yet, scientific knowledge is advancing and research questions are evolving. Therefore, it is important to review the objectives of LTEs over time. A change in their design may be necessary to keep the experimental treatments scientifically interesting, innovative, and relevant in the context of evolving ... -
Impact of conservation farming practices on Aspergillus population density, peanut aflatoxin level, and exposure risk in Zambia
(2024-01-30)Aflatoxin contamination in peanuts (Arachis hypogaea L.) by aflatoxin-producing Aspergillus spp. is a serious problem worldwide affecting human health and restricting trade. Recently, conservation agriculture practices such as minimum tillage, crop rotation, soil surface cover, intercropping, and planting in basins alongside trees that enhance soil fertility, have been introduced in Zambia as tools to conserve soil moisture, increase peanut yield, and reduce the risk of aflatoxin contamination. ...
