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Impacts of farming advisory videos hinge on the goals of extension actors that share them
No full textThis study examined how and why extension workers shared farming videos with farmers, revealing divergent appropriation patterns and their implications for digitization in agriculture. 294 extension workers in Bihar (India) were asked to circulate three wheat agronomy videos with farmers. Extension workers' circulation of these videos was observed using link tracking, phone surveys, and follow-up interviews. Results were analyzed using a novel analytic framework based in affordance theory. Extension workers varied widely in how much, how, and why they shared the farming videos. This variation was underpinned by extension workers' differing incentives and goals. In other words, extension workers heterogeneously appropriated-rather than homogeneously deployed-the practice of sharing farming videos. Some but not all of these appropriations were desirable from the perspective of service managers. For theory, extension workers' appropriations of farming videos demonstrate that prevalent conceptualizations of digital agricultural technologies do not account for the adaptation of these technologies by farmers and other actors in agricultural innovation systems. For digital agriculture evaluators, the findings caution against the prevalent focus on averaging effects of interventions and highlight the need to examine the variability of these effects within and across interventions. For extension service managers, the findings emphasize the importance of engaging extension actors with farmer-aligned incentives and goals. This study was limited in focusing on the video-sharing behaviors of human extension actors and not on algorithmic extension actors, like YouTube or farming advisory chatbots powered by large language models. However, the findings have implications for both: just as human actors variably appropriate digital tools, algorithmic extension actors also embed implicit goals that shape how agricultural information circulates. Future research should examine the goals and behaviors of these algorithmic actors that have increasing influence in agricultural innovation systems.3021–303
Genetic diversity and population structure of sweetpotato accessions (Ipomoea batatas [L.] Lam.) revealed by single nucleotide polymorphism markers
No full textUse of molecular markers has improved the analysis of genetic variation by eliminating environmental influences on genotype performance. The objective of this study was to assess the genetic diversity (GD) and population structure of 327 sweetpotato genotypes sourced from the major sweetpotato-growing regions of Zimbabwe and from the International Potato Centre (CIP) in Mozambique using low-density Diversity Array Technology (DArTseq) SNP chip covering the 90 chromosomes of sweetpotato. The genotypes' GD varied from 0.12 to 0.50, with a mean of 0.36. The mean PIC value of the SNP markers was 0.29. As SNP markers are biallelic with a maximum PIC of 0.50, this value indicates a moderate level of polymorphism. There was a good representation of minor alleles within the population, with an average minor allele frequency (MAF) of 0.26. The average observed heterozygosity of 0.12 was consistent with the cross-pollinating system in sweetpotato but could perpetuate a narrow genetic base. There was limited interbreeding between the populations of sweetpotato, as indicated by a mean fixation index (F) of 0.68. The high F values indicated that most alleles per genotype were contributed by one parent, which is unusual in allogamous species such as sweetpotato. The sweetpotato genotypes in this study could be clustered into two sub-populations with significant differences within the sub-populations. Genetic variation among genotypes is essential for the improvement of sweetpotato. Still, significant genetic gain could be achieved by cross-pollinating divergent genotypes with high MAF to create segregants with rare alleles. It is, thus, important to capture the rare alleles as they help adapt to current and future environmental shifts
Del campo a los datos: aprendizajes de la temporada P-V2024 en Texcoco. Resultados de ensayos con maíz, trigo, cebada, frijol y girasol, y experiencias con productores del ciclo Primavera-Verano 2024
No full text41 page
Natural variation of the holobiont for sustainable agroecosystems
No full textPlant evolution is largely driven by plant–microbe interactions, yet the ecology of the plant holobiont is not well understood at a molecular level. However, these relationships hold diverse benefits for sustainable agriculture as nature-based solutions (NbS). We propose a workflow to enhance understanding of natural variation in the plant–soil microbiome holobiont, addressing key challenges like growth promotion, stress resilience, nitrogen use efficiency (NUE), biological nitrification inhibition (BNI), healthy soils, and improving fertilization practices towards a more natural agroecosystem. We discuss a panome-wide association study (PWAS) approach to discover and incorporate novel genetic diversity from exotic germplasm into breeding populations. Ultimately, understanding natural variation of the holobiont in agroecosystems will contribute to the development of novel climate-resilient crop varieties for food security.972-97
Climate information services enhance farmers' resilience to climate change: Impacts on agricultural productivity
No full textEthiopia is a climate "hotspot" where the variable and changing climate periodically threatens agricultural production, food security, and human well-being. Using two-rounds of Feed the Future program survey data that cover 3,799 farming households in five major regions in Ethiopia, and employing panel data estimation methods, we analyze the potential impact of weather and climate services (WCS) on agricultural productivity and farmers' resilience in Ethiopia. We found that access to WCS increases the productivity of maize and wheat crops by 27 % and 17 %, respectively. These estimates are comparable to or higher than conventional yieldincreasing production technologies such as fertilizer and improved seeds. Despite such a strong productivity effect, access to WCS is limited to only 18 % of the surveyed farmers. This study adds to the existing body of evidence on the significant positive impact of WCS, and affirms the importance of weather and climate information service products to enhance farmers' resilience to climate risk. Further analyses are needed to estimate the value to Ethiopia's smallholder farmers, especially those who are most vulnerable to climate-related hazards, of increasing investment in improving seasonal climate forecasts, mainstreaming weather and climate services in the agricultural extension system, including through National Framework for Climate Services (NFCS), and supporting farmer decision-making with climate-informed digital advisory tools and training
Farmers' pesticide use, disposal behavior, and pre-harvest interval: a case study from Nigeria
No full textIn Sub-Saharan Africa, small farmers rely heavily on synthetic pesticides, the overuse of which poses significant risks to human health, the environment, and food safety. Yet detailed empirical evidence on the knowledge and drivers of pesticide management practices remains scarce, limiting insights for policymakers and development practitioners. To address this gap, we leveraged data collected from 1,556 tomato producers in Northern Nigeria to investigate the determinants of pesticide use behavior using a sequential-exploratory mixed-method approach. We examined a broader range of pest management-related practices than prior literature, including safety equipment usage, pesticide disposal methods, and adherence to pre-harvest intervals (PHIs)-the intervals between the last pesticide application and the crop harvest. We found substantial non-compliance with the recommended practices: 45% of farmers reuse empty pesticide containers for other purposes, 14% discard them on the farm, 15% burn containers in open fires, and 40% harvest tomatoes within 1-5 days after pesticide application, violating the 7-day PHI guideline. These findings suggest that many tomato farmers adopt unsafe practices, which have adverse implications for their health, the environment, and the safety of food for consumers. We show that training on pesticide disposal and midstream market channels (e.g., wholesalers and aggregators) are strongly correlated with improved pesticide handling and PHI compliance. Overall, our results underscore the need for targeted training programs to enhance farmers' awareness of safe pesticide application, disposal practices, and PHI adherence. These efforts should be complemented by stronger regulatory frameworks and mechanisms to align farmer pesticide use practices with consumer preferences for safe products, as observed in the higher PHI adherence among farmers selling to midstream actors
Evaluation of fusarium head blight resistance through a genome-wide association study in CIMMYT and South Asian wheat germplasm
No full textFusarium head blight (FHB) is an important disease throughout the world due to its strong association with yield reduction, quality deterioration, and mycotoxin contamination in wheat. The use of FHB-resistant genotypes in wheat production can significantly reduce damage. The current study screened a panel of bread wheat from CIMMYT and South Asian countries for FHB resistance to identify promising genotypes useful for wheat breeding and to map the associated genomic regions and linked molecular markers through a genome-wide association study (GWAS). Spray-inoculated field experiments were conducted at CIMMYT, Mexico, over three years, and a wide range of phenotypic variations was observed. Four lines, CIM-39, CIM-29, CIM-9, and CIM-3, exhibited consistent resistance across experiments, with FHB indices ranging from 6.5 to 8.1. Genotyping was conducted using the Illumina Infinium 15 K Bead Chip, and 11,184 high-quality SNP markers were obtained and used for GWAS. Nineteen significant marker-trait associations (MTAs) were detected, among which MTAs at Ra_c58315_265 on 1A and Tdurum_contig102328_129 and Ku_c20136_198 on 7B showed reproducible results, with phenotypic effects on FHB resistance of 6.05%, 3.54%, and 3.92%, respectively. Several genes associated with disease resistance were found near the significant SNPs. The identified resistant genotypes and markers may be useful in future marker-assisted breeding in wheat
Evaluating the effectiveness of selection indices and their genomic prediction using environmental and historical rice data
No full textImproving genetic gains in rice breeding programs requires accurate prediction methods for selection indices. Effective use of genomic prediction could significantly accelerate breeding cycles. The Smith index method (SIM), the eigenvalue selection index method (ESIM), and the desired gain index (DG) are linear combinations of trait phenotypic values y (I=b ' y), and while the SIM and ESIM predict the net genetics merit (H=w ' c), where w is the vector of economic weights and c is the unobserved genotypic values, the DG predicts the mean of genotypic values. To enhance genomic prediction accuracy, mixed linear and Bayesian models incorporate molecular markers to estimate genomic effects, resulting in genomic estimated breeding values. This study evaluated (1) the efficiency of the SIM, ESIM, and DG through their main parameters and (2) the predictive accuracy of 5 genomic prediction models utilizing historical rice (Oryza sativa) data from 2018 to 2021 to predict selection indices for 2022. The correlation between observed and predicted indices assessed the effectiveness of each genomic model. Models incorporating year-specific and environmental covariates significantly improved predictive performance. These findings underscore the importance of environmental covariates and indicate that the SIM is the most effective method for maximizing key index parameters, while the ESIM provides the best predictive accuracy for indices. Consequently, rice breeders are encouraged to use these indices to enhance genetic gains per selection cycle
A portable, nanopore-based genotyping platform for near real-time detection of Puccinia graminis f. sp. tritici lineages and fungicide sensitivity
No full textBackground: Fungal plant disease outbreaks are increasing in both scale and frequency, posing severe threats to agroecosystem stability, native biodiversity and food security. Among these, the notorious wheat stem rust fungus, Puccinia graminis f.sp. tritici (Pgt), has threatened wheat production since the earliest days of agriculture. New Pgt strains continue to emerge and quickly spread over vast distances through the airborne dispersal of asexual urediniospores, triggering extensive disease outbreaks as these exotic Pgt strains often overcome resistance in dominant crop varieties of newly affected regions. This highlights the urgent need for a point-of-care, real-time Pgt genotyping platform to facilitate early detection of emerging Pgt strains. Results: In this study, we developed a simple amplicon-based re-sequencing platform for rapid genotyping of Pgt isolates. This system is built around a core set of 276 Pgt genes that we found are highly polymorphic between Pgt isolates and showed that the sequence of these genes alone could be used to accurately type Pgt strains to particular lineages. We also developed a simplistic DNA preparation method and an automated bioinformatic pipeline, to enable these Pgt gene markers to be sequenced and analysed rapidly using the MinION nanopore sequencing device. This approach successfully enabled the typing of Pgt strains within approximately 48 h of collecting Pgt-infected wheat samples, even in resource-limited locations in Kenya and Ethiopia. In addition, we incorporated monitoring capabilities for sequence variations in Pgt genes that encode targets of the azole and succinate dehydrogenase inhibitor fungicides, enabling real-time tracking of potential shifts in fungicide sensitivity. Conclusion: The newly developed Pgt Mobile And Real-time, PLant disEase (MARPLE) diagnostics platform we established, now allows precise typing of individual Pgt strains while simultaneously tracking changes in fungicide sensitivity, providing an early warning system for potential indicators of changes in the Pgt population and emerging fungicide resistance. Further integration of this Pgt MARPLE diagnostics platform into national surveillance programmes will support more informed management decisions and timely responses to Pgt disease outbreaks, helping reduce the devastating crop losses currently caused by this 'cereal killer'
More bang for your buck: potential gains through optimizing maize breeding schemes in sub-Saharan Africa
No full textIncreasing the rate of genetic gain in breeding programs is a critical component of crop genetic improvement strategies to increase yields in smallholder farmers' fields. While a growing array of technologies and tools are being deployed within breeding programs, optimizing resource allocation could provide a simple yet effective way to increase genetic gain, particularly within resource-constrained breeding programs. The objective of this study was to demonstrate that an easy-to-use deterministic model and a breeding costing tool could identify key modifications to improve the efficiency of breeding within the Zimbabwean national maize breeding program. The current program uses pedigree inbreeding, with a 4-1-1 tester scheme, and relatively low selection intensity. The method of inbreeding, test-crossing schemes, and selection intensity were modified within the current program budget. A combination of using doubled haploid lines, a 2-2-1 tester plan, and increased selection intensity improved gain per cycle by 42.8%, gain per year by 161.8%, gain per dollar by 43.1%, and decreased cost of one unit of genetic gain by 28.5% without a change in budget. Our results highlight how a simple deterministic model can identify steps to greatly improve breeding efficiency within resource-constrained breeding programs