Africa Rice Center

Efficient fertilizer application is vital for enhancing maize production and profitability in Sub-Saharan Africa, where soil fertility varies widely across regions. This study aimed to develop a machine learning approach for generating site-specific fertilizer recommendations for maize production in Ghana and to evaluate its performance against conventional and semi-mechanistic approaches. A random forest machine learning model was trained on 482 maize yield experiments, consisting of 3136 yield observations collected from 1991 to 2020, to predict maize yield response to different fertilizer rates. The model incorporated multiple explanatory variables, including soil properties, climate conditions, and management practices, to generate fertilizer response curves from which fertilizer recommendations were derived for 14 sites across three agro-ecological zones in Ghana where field validation experiments were conducted. On these sites, the recommendations were compared with recommendations derived from the Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS), Conventional Fertilizer Dose Response (CFDR), and Updated Conventional Fertilizer Dose Response (UCFDR) approaches and validated through field experiments. The machine learning approach generally recommended lower rates of phosphorus and potassium than the other approaches, while nitrogen recommendations were comparable. In the Guinea Savanna zone, the recommendations from the machine learning approach outperformed those from the other approaches, producing higher mean yields for three out of the four sites in the zone. In the Forest-Savanna Transition (FST) zone, the machine learning model recommendations led to higher mean yields at four sites, while the approaches based on QUEFTS and UCFDR performed best at two other sites. In the Semi-deciduous Forest zone, the recommendations of the QUEFTS approach resulted in the highest mean yields at three sites, and CFDR at one site. Despite high input prices during the period of experimentation, the machine learning approach-based recommendations demonstrated higher net profit margins in the FST zone, suggesting cost-effectiveness in this zone. These findings indicate that site-specific fertilizer recommendations are more efficient than blanket recommendations and that machine learning approaches offer a promising and innovative approach for generating cost-effective, site-specific fertilizer recommendations in tropical climates. • ML and QUEFTS approaches provided site-specific fertilizer recommendations. • ML and QUEFTS outperformed conventional fertilizer recommendation approaches. • CFDR and UCFDR were constrained by generalized, non-site-specific recommendations. • Machine learning supports sustainable fertilizer use.

Abstract Background Insecticide resistance in the vectors population remains a major challenge to the effective control of arboviral diseases. In the current context where Aedes vectors have developed resistance to pyrethroids, it is essential to explore alternative insecticidal compounds. This study aimed to assess the resistance profiles of the main arbovirus vectors to next-generation insecticides, specifically Chlorfenapyr and Pyriproxyfen. Methods The study was conducted in four municipalities in southern Benin. Vectors were collected using ovitraps and reared to the adult stage. Aedes aegypti and Aedes albopictus populations were used directly for the various tests. CDC bottle bioassays were performed to evaluate vector susceptibility to Chlorfenapyr and to assess the reproductive inhibition properties of Pyriproxyfen. Cone and tunnel tests were conducted to determine the bioefficacy of Royal Guard ® and Interceptor ® G2 long-lasting insecticidal nets (LLINs). Results Results revealed full susceptibility of both Aedes aegypti and Aedes albopictus to Chlorfenapyr, with mortality rates ranging from 98% to 100% across all municipalities. Pyriproxyfen significantly reduced oviposition in Aedes aegypti, with inhibition rates ranging from 91.7 % to 99% across all study sites. Similar outcomes were observed in Aedes albopictus, with oviposition rates ranging from 0% (0–3.6) to 6.1% (2.3–12.9). Blood-feeding and penetration rates for both species exposed to Interceptor® G2 were low, while mortality rates remained high. Both types of LLINs demonstrated optimal efficacy against the susceptible Aedes aegypti strain (Rockefeller). Conclusion The study demonstrated the effectiveness of Chlorfenapyr and Pyriproxyfen as promising alternatives for managing pyrethroid-resistant Aedes populations. The LLINs impregnated with these compounds Royal Guard® (alpha-cypermethrin + Pyriproxyfen) and Interceptor® G2 (alpha-cypermethrin + Chlorfenapyr) also proved effective against wild Aedes populations and could serve as valuable tools in arbovirus vector control strategies.

Central nervous system tumors present significant diagnostic and therapeutic challenges, as WHO histomolecular prognostic criteria are not always optimal. Decision-making increasingly relies on multidisciplinary team meetings (MDTs), which require highly qualified specialists. We aimed to assess available human resources and propose a framework for subregional collaboration through a West African neuro-oncology MDT. A multicenter descriptive study was conducted via an online questionnaire from April 13 to June 15, 2025, involving 35 healthcare professionals from nine West African countries. Participants included 45.7% neurosurgeons, over 57% with <3 years' experience. Most managed <100 patients/year, and 90% performed <100 tumor excisions. Awake surgery and stereotactic biopsy were rare. Access to chemotherapy, pathology, immunohistochemistry, and molecular biology was reported by 83%, 80%, 51%, and 14% of respondents, respectively. Median turnaround time was about 3 weeks for histopathology and about 1 month for immunohistochemistry. Clinical trial access was available to 26%. Neurosurgeon density was <1 per million inhabitants, peaking in Senegal (1 per 700,000). Only 34% reported functional MDTs. Nearly all participants (95%) supported establishing a subregional network with regular online MDTs (monthly or bimonthly) and a specialized interuniversity degree. MDTs are essential in neuro-oncology, enabling individualized therapeutic planning. Given critical workforce shortages in West Africa, a subregional collaborative MDT network could optimize patient care, enhance resource sharing, and standardize management across the region.

This study explores the nutritional enhancement of germinated brown rice (GBR), commonly referred to as GABA rice, produced from Nigerian rice cultivars (FARO 44, FARO 52, and FARO 57). Paddy rice was germinated at 35°C for 0 (control), 12, 24, and 36 h, followed by parboiling and dehusking to obtain GBR. Nutritional analyses focused on mineral, vitamin, and phytic acid contents. Germination significantly increased macro-minerals, including calcium, magnesium, phosphorus, and sodium, by up to 109.8%, 22.1%, 12.1%, and 149.0%, respectively after 36 h of germination. The levels of trace minerals such as zinc, iron, manganese, selenium, and cerium also increased, while phytic acid level decreased with longer germination durations. Vitamin content improved markedly, with increases of 387.5% for B1, 440.0% for B2, and 56.8% for vitamin E, after 36 h of germination. A 24 h germination period was optimal for mineral enrichment, while 36 h maximized the vitamin levels. These findings suggest that GBR, when integrated into conventional rice processing systems, could offer a cost-effective dietary intervention for addressing micronutrient deficiencies and managing metabolic health disorders.

• Increase degree of milling (DOM) enhances appearance quality of rice but substantially depletes micronutrient content. • Improved and imported parboiled rice retains more minerals than rudimentary parboiled and white rice. • Glycemic index (GI) is affected by rice variety, analytical procedure, parboiling and milling. • Most rice consumers reject rice that is chalky, hard in texture, high in amylose, and contaminated. Rice is an important source of calories and nutrients for people in low- and middle-income countries. In the quest to respond to consumer preferences and attract premium prices, paddy processors increase the degree of milling (polishing), largely affecting nutritional composition and economic value of milled rice. Milling and parboiling are crucial unit processing operations affecting the quality profile of rice. The literature poorly reports on milling and parboiling operations that provide economic and nutritional gains or losses. Thus, there are no standard milling and parboiling regimes recommended to influence technological and policy changes in favor of public health and nutrition. In this comprehensive review, rice milling and parboiling operations associated with nutritional, economic, food safety and environmental benefits have been presented and discussed. Optimal milling and parboiling strategies that provide nutritional, economic, food safety and environmental gains are proposed as alternatives to conventional processing technologies and practices. Improved parboiling and moderate degree of milling in two-stage systems appear to provide better economic and nutritional benefits.

ABSTRACTMalnutrition and the consumption of unhealthy diets remain a global challenge. Most of the malnourished and food‐insecure people live in poor rural communities, where farming is the main livelihood activity. Using robust data collected from a random cross‐sectional sample of 268 households, we investigate whether farmers' involvement in agricultural diversification contributes to dietary diversity and quality in poor rural Türkiye. We also examine whether market participation influences the association between agricultural diversification and dietary diversity and quality. The results illustrate a statistically significant influence of five agricultural diversification indicators on three dietary diversity and quality indices over a 24‐h recall period, with the livestock richness score more strongly correlated across different dietary diversity and quality indices than the crop richness score. Furthermore, we find that the heterogeneous associations between market participation and agricultural diversification significantly influence higher dietary diversity and quality indices over a 24‐h recall period. Own production of tubers and livestock (meat) increased dietary diversity and quality, while the own production of olive crops (oils) did not increase dietary diversity. Own production of tubers significantly increased own consumption of tubers, while own production of cereals, tubers, vegetables, meat, egg, milk and dairy, and oils food groups significantly increased own consumption of other food groups. The overall influence of agricultural diversification on households' dietary diversity and quality in poor rural Türkiye is modest, mainly due to the low levels of diversification.

BackgroundRice blast, caused by Pyricularia oryzae (teleomorph: Magnaporthe oryzae), is one of the most economically damaging diseases affecting rice worldwide. While the evolutionary origins and genetic structures of Asian and European P. oryzae populations are relatively well characterized, African isolates remain underexplored. This knowledge gap impedes the development of informed management strategies for rice blast in the region. The present study was conducted to characterize the genetic origins, population structure, admixture, demographic history, and effector gene diversity of P. oryzae isolates in SSA, and to elucidate their evolutionary trajectories and implications for disease management.MethodsA total of 180 genome sequences (45 from SSA, 135 from other regions) were analyzed using population genomic approaches. Phylogeographic reconstructions, demographic modeling, and genome-wide association studies were performed to trace migration events, quantify genetic diversity, and identify candidate adaptation genes. Effector gene repertoires were also examined for diversity and selection signatures. ResultsOur findings provide new dates for the divergence of SSA populations from Asian populations. The introduction of P. oryzae into Africa occurred mainly from China in the late 19th century, initially in West Africa (WA; Mali and Burkina Faso), and subsequently in Uganda and Madagascar during the early 20th century, before extending to the wider African region, with subsequent repeated introductions. Tajima’s D and demographic modeling suggested complex population dynamics shaped by migration and asymmetric founder events, highlighting considerably shared genetic ancestry between Asia and East Africa (EA), in contrast with that between Asia and WA. Genome-wide association analysis identified a specific set of single nucleotide polymorphism markers, along with several candidate genes linked to adaptation. Effector analysis revealed that SSA isolates harbor fewer effectors and exhibit lower genetic diversity than Asian populations, with some effectors under positive selection, particularly in WA.DiscussionP. oryzae populations in SSA are shaped by historical introductions, founder events, and region-specific adaptation processes. While WA populations have diverged significantly from their Asian ancestors, gene flow within SSA connects regional populations, and effector gene diversity reflects both conserved virulence strategies and adaptation to local hosts. Overall, this study improves the existing knowledge on P. oryzae populations in SSA and underscore the need for integrated management strategies that consider both historical and contemporary pathogen dynamics in Africa.