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As biofábricas, novos modelos de produção e acesso a insumos agrícolas na América latina
No full textA produção e o acesso a alternativas aos insumos químicos estão atraindo o interesse de muitos atores do setor agropecuário. Na América Latina, o crescente desenvolvimento de insumos biológicos - incluindo biofertilizantes, agentes de controle biológico e bioestimulantes - está oferecendo soluções para esses desafios (ver Perspectives 55, maio 2021). Esse boom é resultado de anos de investimento público em pesquisa e do dinamismo industrial no desenvolvimento de tecnologias baseadas em microrganismos, macroorganismos ou extratos de plantas. Ademais, diferentemente dos canais tradicionais de fornecimento de insumos agrícolas, ONGs, redes de agricultores, políticas públicas e até mesmo alguns agentes privados estão incentivando a produção de bioinsumos em biofábricas, diretamente nas fazendas ou em instalações comunitárias em áreas rurais. Essas biofábricas abrem novas perspectivas, contudo, ao mesmo tempo, enfrentam grandes desafios.1–
Exploring natural genetic diversity in a bread wheat multi-founder population: dual imaging of photosynthesis and stomatal kinetics
No full textRecent research has shown that optimizing photosynthetic and stomatal traits holds promise for improved crop performance. However, standard phenotyping tools such as gas exchange systems have limited throughput. In this work, a novel approach based on a bespoke gas exchange chamber allowing combined measurement of the quantum yield of PSII (Fq'/Fm'), with an estimation of stomatal conductance via thermal imaging was used to phenotype a range of bread wheat (Triticum aestivum L.) genotypes. Using the dual-imaging methods and traditional approaches, we found broad and significant variation in key traits, including photosynthetic CO2 uptake at saturating light and ambient CO2 concentration (Asat), photosynthetic CO2 uptake at saturating light and elevated CO2 concentration (Amax), the maximum velocity of Rubisco for carboxylation (Vcmax), time for stomatal opening (Ki), and leaf evaporative cooling. Anatomical analysis revealed significant variation in flag leaf adaxial stomatal density. Associations between traits highlighted significant relationships between leaf evaporative cooling, leaf stomatal conductance, and Fq'/Fm', highlighting the importance of stomatal conductance and stomatal rapidity in maintaining optimal leaf temperature for photosynthesis in wheat. Additionally, gsmin and gsmax were positively associated, indicating that potential combinations of preferable traits (i.e. inherently high gsmax, low Ki, and maintained leaf evaporative cooling) are present in wheat. This work highlights the effectiveness of thermal imaging in screening dynamic gs in a panel of wheat genotypes. The wide phenotypic variation observed suggested the presence of exploitable genetic variability in bread wheat for dynamic stomatal conductance traits and photosynthetic capacity for targeted optimization within future breeding programmes.6733–674
Training of women and youth seed producers on business and financial management: Songwe, Tanzania
No full text7 page
Investigating genomic prediction strategies for grain carotenoid traits in a tropical/subtropical maize panel
No full textVitamin A deficiency remains prevalent on a global scale, including in regions where maize constitutes a high percentage of human diets. One solution for alleviating this deficiency has been to increase grain concentrations of provitamin A carotenoids in maize (Zea mays ssp. mays L.)-an example of biofortification. The International Maize and Wheat Improvement Center (CIMMYT) developed a Carotenoid Association Mapping panel of 380 inbred lines adapted to tropical and subtropical environments that have varying grain concentrations of provitamin A and other health-beneficial carotenoids. Several major genes have been identified for these traits, 2 of which have particularly been leveraged in marker-assisted selection. This project assesses the predictive ability of several genomic prediction strategies for maize grain carotenoid traits within and between 4 environments in Mexico. Ridge Regression-Best Linear Unbiased Prediction, Elastic Net, and Reproducing Kernel Hilbert Spaces had high predictive abilities for all tested traits (beta-carotene, beta-cryptoxanthin, provitamin A, lutein, and zeaxanthin) and outperformed Least Absolute Shrinkage and Selection Operator. Furthermore, predictive abilities were higher when using genome-wide markers rather than only the markers proximal to 2 or 13 genes. These findings suggest that genomic prediction models using genome-wide markers (and assuming equal variance of marker effects) are worthwhile for these traits even though key genes have already been identified, especially if breeding for additional grain carotenoid traits alongside beta-carotene. Predictive ability was maintained for all traits except lutein in between-environment prediction. The TASSEL (Trait Analysis by aSSociation, Evolution, and Linkage) Genomic Selection plugin performed as well as other more computationally intensive methods for within-environment prediction. The findings observed herein indicate the utility of genomic prediction methods for these traits and could inform their resource-efficient implementation in biofortification breeding programs
Land and technology requirements for economically prosperous smallholder farming in sub-Saharan Africa: Evidence from Tanzania
No full textMaking a living from a small farm is difficult in sub-Saharan Africa. In this paper, we quantify how difficult, using a simple, robust, relation between per capita daily income from farming (FPDI), land per capita and whole-farm net profitability per hectare. This relation allows the calculation of the land area required to generate various levels of household income as a function of farm performance. We use nationally representative household data for Tanzania to investigate the range of whole-farm profitability and to estimate an upper limit for it. For 6818 cases where households with land reported figures for gross crop and livestock revenues and for costs in any of the three years 2009, 2011 or 2013, actual median whole-farm net profitability was only 238/ha/y, i.e. a net loss. The maximum whole-farm profitability achieved was 2742/ha/y with it. We evaluated actual and potential farm performance for their ability to generate a range of values of FPDI up to $10 per person per day. Most farms are not very profitable, particularly when household labour costs are considered, and few would be considered economically prosperous. Our analysis underscores the fact that improving their operations or adopting new technologies alone is unlikely to lift many smallholder farmers out of poverty in developing countries, given typical farm size distributions and reasonable assumptions about the realized economic returns to adoption of currently available agricultural technologies. While continued agricultural R&D investments are certainly worthwhile, such efforts alone will be insufficient to meaningfully address welfare needs of the world's rural poor. This suggests that agricultural development programs should expand their attention to incorporate off-farm and non-farm components of the rural economy.131–14
Knowledge, attitudes, and food safety practices of informal market maize grain vendors and consumers in Meru County, Kenya
No full textAflatoxin contamination in food poses a significant health risk, especially in low- and middle-income nations. While there is a need to increase food safety, there is a lack of aflatoxin-related sociodemographic factors, knowledge, attitudes, and practices (KAPs) among aflatoxin-risk populations. The study is aimed at collecting information from the vendors and consumers of maize grains to investigate their sociodemographic factors and KAPs of aflatoxin contaminations in Kenya's small- and medium-sized informal markets. A cross-sectional survey using a simple random sampling approach was conducted from July 2022 to August 2022 in Meru County, Kenya. Vendors and consumers of maize grain markets were interviewed using face-to-face interviews and semistructured questionnaires. Females were the predominant gender among the maize grain vendor (82.7%) and consumer (83.72%) participants. Most vendors (95.7%) and consumers (94.2%) have formal education. Almost all vendors (96.2%) and consumers (95.3%) check for maize selling and purchasing quality. The proportion of visibly mouldy grains (25.5%, 29.0%), moisture level (20.2%, 12.9%), and size of grains (11.4%, 14.8%) were the commonest quality dimensions checked by vendors and consumers, respectively. Most vendors (86.8%) and consumers (70.9%) have heard about aflatoxin, but only 48.2% of the vendors and 52.1% of the consumers were aware and could mention the correct aflatoxin health effects. Vendors' and consumers' KAPs on aflatoxin varied significantly (p < 0.05) across subcounties, education levels, genders, and ages. Promoting public awareness, building capacity, and implementing aflatoxin-related policies at all levels are crucial to ensure food safety
Mapping field-level maize yields in Ethiopian smallholder systems using sentinel-2 imagery
No full textRemote sensing offers a low-cost method for estimating yields at large spatio-temporal scales. Here, we examined the ability of Sentinel-2 satellite imagery to map field-level maize yields across smallholder farms in two regions in Oromia district, Ethiopia. We evaluated how effectively different indices, the MTCI, GCVI, and NDVI, and different models, linear regression and random forest regression, can be used to map field-level yields. We also examined if models improved by adding weather and soil data and how generalizable our models were if trained in one region and applied to another region, where no data were used for model calibration. We found that random forest regression models that used monthly MTCI composites led to the highest yield prediction accuracies (R-2 up to 0.63), particularly when using only localized data for training the model. These models were not very generalizable, especially when applied to regions that had significant haze remaining in the imagery. We also found that adding soil and weather data did little to improve model fit. Our results highlight the ability of Sentinel-2 imagery to map field-level yields in smallholder systems, though accuracies are limited in regions with high cloud cover and haze
Food systems accelerator report: Strengthening smallholder sorghum contract farming business model in Mbire District
No full text16 page
Corrigendum to “Cost-effective opportunities for climate change mitigation in Indian agriculture” [Sci. Total Environ. 655 (2019) 1342–1354]
No full textComparing traditional and commercial nixtamalization of three maize landraces: Impact on pozole quality and consumer acceptance
No full textOne of the most typical dishes of traditional Mexican cuisine is pozole, made with nixtamalized maize. This dish has a special place as part of the identity of Mexican culture. However, it is time-consuming to prepare. With an increasing demand for precooked maize for pozole and the limited information on its preparation process, this study aims to assess the impact of both traditional (TN) and commercial nixtamalization (CN) on the quality of processed maize and its reception by consumers, focusing on the three most popular maize landraces used in pozole recipes. This study was carried out with the Cacahuacintle (‘CAC’), Elotes Occidentales (‘EO’) and Ancho (‘AN’) landraces, which were nixtamalized using the traditional method (only lime) and the commercial method (lime + additives) and the grain was flowered. The quality of the flowered grain was determined, and a sensory analysis consisting of magnitude of difference tests, a descriptive analysis, affective test and evaluation of consumer preferences was carried out. The ‘CAC’ landrace, when processed traditionally, yielded the highest sensory and commercial quality. The ‘EO’ landrace demanded a longer flowering time, resulting in less volume but retaining the aleurone layer. This characteristic helped preserved a portion of the anthocyanins. Consistently, maize landraces subjected to traditional nixtamalization displayed higher ratings for attributes related to masa and nejayote aroma. The ‘CAC’ landrace subjected to CN faced challenges in acceptability due to odors of acetic acid and sulfuric acid. These findings underscore the importance and advantages the TN techniques. They also emphasize the need to preserve grain quality and meeting consumer preferences when exploring alternative maize processing methods for emerging markets