Farmers In Low-income Countries Research Articles

Design and implementation of a cost-aware and smart oyster mushroom cultivation system

Mushrooms are a nutritious food source, which can play a crucial role in providing affordable sources of proteins, vitamins and minerals for people worldwide, but their cultivation requires extensive training and considerable relevant expertise in order to fine-tune multiple environmental parameters.Internally displaced people in the Northern regions of Syria rely on very small-scale traditional oyster mushroom production, which cannot meet their local demand. Many international and local non-governmental organizations (NGOs) working for Syrian refugees, work on mushroom cultivation projects. They have reported significant difficulties and challenges in mushroom cultivation amongst the targeted beneficiaries. Therefore, the two main questions driving this research are: (1) How can organic mushroom cultivation be promoted using a robust and affordable intelligent mushroom farming system? (2) How can organic mushroom farming practices be simplified to support internally displaced and refugee Syrians?This research evaluates the process of automating mushroom cultivation by designing and implementing a smart oyster (Pleurotus ostreatus) mushroom farming system to remotely monitor and manage environmental parameters, such as temperature, humidity, air quality and illumination, inside the farm. Furthermore, ready and dedicated user-friendly web interfaces were also implemented to enable farmers to remotely monitor and manage their farms through the Internet. As a result, a dependable and cost-effective intelligent oyster mushroom cultivation system was designed and implemented in this work. The system includes remote monitoring and management via user-friendly interfaces. This simplifies mushroom cultivation for not only refugees and displaced communities, but also for mushroom farmers in low-income countries. This work can contribute to the eradication of poverty and hunger, in line with the United Nations Sustainable Development Goals one and two.

Smallholder farmers’ knowledge, attitudes, and practices (KAP) regarding agricultural inputs with a focus on agricultural biologicals

There is a general drive to reduce pesticide use owing to the potential negative effects of pesticides on the environment and human health. The EU Commission, for example, through its “Farm to Fork Strategy,” has proposed to decrease the use of hazardous chemical pesticides by 50% by 2030. In addition, smallholder farmers in low-income countries do not always follow pesticide safety precautions. This necessitates the introduction of low-risk crop protection strategies also suited for these farmers. Agricultural biologicals can substitute for, or at least partially replace hazardous chemical pesticides. While the market for and use of biologicals is growing quickly in industrialized countries, this practice remains limited in sub-Saharan Africa. To understand the reason behind the low adoption of biologicals, this study examined the knowledge, attitudes, and practices toward biologicals among 150 smallholder farmers in the Chole district in Ethiopia. All farmers used chemical pesticides and/or inorganic fertilizers to protect crops, improve yields, and comply with government regulations. The use of biologicals was, however, restricted to one group of biologicals, bio-fertilizers, which approximately 60% of farmers used, and no use of biologicals for plant protection was reported. Even though the understanding of the concept of biologicals was deemed high among respondents, the majority (90%) did not identify biologicals as safer alternatives to conventional agricultural inputs. More than half of the respondents (54%) did not recommend biologicals as safer alternatives to their colleagues. Nevertheless, even if the responding farmers did not perceive biologicals as risk-free, they had a positive attitude towards biologicals when it came to producing healthy food and increasing crop yields and incomes. In comparison to the positive attitude, farmers’ knowledge and practice of biologicals were generally low; thus, efforts are needed to create awareness among farmers.

Nutritional, ecological and livelihood significance of Moringa oleifera: A review

The potential ecological and livelihood benefits of Moringa plants are often overlooked. There is a need to raise awareness and encourage farmers and decision makers to adopt Moringa on marginal and degraded lands with changing climate risks. Previous studies have focused mainly on the pharmacological uses and oil content from a commercial point of view and failed to explore its ecological benefits and economic potential to address the growing problems of global food insecurity, malnutrition, and climate risks. Planting Moringa on unused and marginal land can improve soil fertility, food production, and resilience to climate change, offering a significant opportunity for diversification of livelihoods and economic development in the changing climate. Henceforth, this study compiles scientific evidence through a systematic literature search to highlight the ecological benefits and livelihood opportunities associated with the use of Moringa. Initially, we retrieved 206 pieces of global literature and, through the application of inclusion and exclusion criteria, extracted information from 22 articles. Various studies have consistently shown that Moringa leaves are highly nutritious and that their consumption can combat food and nutrition insecurity in low-income countries. Its seeds offer the potential for the commercial production of oils with heart-healthy properties. The oil is stable and suitable for cooking and its quality varies depending on location and environmental factors. When included in the diet, Moringa leaves improve the quality and quantity of goat milk and support the growth of fish in aquaculture. The extract of Moringa provides versatile uses in water purification, offering sustainable solutions to water pollution. We thus conclude that Moringa's diverse applications can contribute to the livelihood enhancement and economic well-being of poor and marginalized farmers in low-income countries. Planting Moringa trees in abandoned croplands and other degraded areas can have positive ecological and socioeconomic outcomes for rural communities. However, to support smallholders in low-income countries, favorable policies, field-based research evidences, and products development are crucial.

Applying sunflower oil to rapeseed plants reduces water loss.

Hydrophobic polymers are used as antitranspirants to block stomata and reduce water loss from plants and thus drought stress, although the use of current commercial products is limited because they are expensive. Plant oils may be much cheaper hydrophobic polymers if they have similar efficacy to commercial antitranspirant products. Two experiments with pot-grown rapeseed plants were conducted to compare sunflower oil with the commercially-available antitranspirant di-1-p-menthene (DPM) for efficacy in reducing water loss, and to test for a linear response to increasing oil concentration. Sunflower oil at the same concentration as DPM (0.5%) was similar in efficacy in reducing the rate of water loss, measured as both rate of weight loss of the plant and rate of stomatal conductance decline. There was a linear response to increasing concentrations of oil, as found in previous research with DPM on rapeseed, with a slower rate of water loss the greater the concentration. If other plant oils are equally or more effective in reducing water loss as sunflower oil, there may be potential for plant oils to be used as low-cost antitranspirants to reduce drought damage on large-scale commodity crops, and also by smallholder farmers in low-income countries using locally-produced plant oils. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Participatory Guarantee Systems, a more inclusive organic certification alternative? Unboxing certification costs and farm inspections in PGS based on a case study approach

The importance of Participatory Guarantee Systems (PGS) as an alternative organic certification to third-party certification (TPC) has grown remarkably in recent years. PGS are argued to be less costly than TPC, and adopt the exchange of advice and knowledge as a key element of farm inspections. For these reasons, PGS are promoted as being more accessible for smallholder farmers in low-income countries and as a tool for supporting organic conversion and standard compliance, and ultimately contributing to food system sustainability. PGS certification costs have not yet been studied thoroughly and empirical studies on PGS farm inspections are rare. This paper applies a mixed-methods case study approach in a Costa Rican PGS initiative and explores explicit and implicit PGS certification costs and PGS farm inspections. The framework for assessing actor participation in PGS and transaction cost theory were used as the theoretical foundation. Semi-structured interviews (n = 10), PGS member surveys (n = 17), and participant observations of PGS farm inspections (n = 11) were conducted and complemented with data from internal documents and informal interviews. The results showed that reduced explicit costs for PGS certification were accompanied by substantial implicit costs in terms of the time dedicated to the PGS certification process. These implicit costs were largely attributed to the legal requirements for PGS, and were borne by only a few members, resulting in differences in total certification costs between PGS members. Despite legal formalization, information exchange was an important part of PGS farm inspections. Against the backdrop of small audit teams and low participation in farm inspections, PGS members implementing farm inspections nurtured transparency and an exchange of experience within the PGS. The study provides novel insight into PGS, and defines cost components and PGS characteristics affecting PGS certification costs that may also be relevant to other PGS initiatives and related fields of action.

Policy incentives for smallholder adoption of climate-smart agricultural practices

There is a large and growing literature on the potential use of policy instruments for stimulating the adoption of Climate-Smart Agriculture (CSA) practices amongst smallholders. The objective of this article is to review and understand how the array of potential policy incentives can serve as mechanisms for enhancing adoption and upscaling of potential CSA practices by small-scale farmers in low-income countries. The review follows a matrix approach capturing where specific CSA practices (rows) are supported by typical policy instruments (columns) for enhancing widespread adoption. We first identify six key CSA practices, namely water management, soil and nutrient management, crop tolerance to stress, agroforestry and intercropping, crop rotation and mixed systems, and pest and disease management. Then we discuss the impact of those typical policy instruments, namely market prices, taxes and subsidies, land rights, rural finance, training and information, and certification and labeling. The review finds that most studies on this subject have a rather narrow focus on functional properties of a specific policy instrument and a particular CSA practice, thereby ignoring substitution, complementary or conditional effects between policy measures and CSA practices. Consequently, previous studies identify few incentives, particularly effective on their own. Wider perspectives on impact pathways point to the importance of sequencing and scaling for enhancing farmers' CSA adoption. We therefore advocate for more integrated approaches that also consider indirect effects of policy instruments on CSA adoption and pursue their systematic anchoring through successful policies that enhance widespread adoption.

Can Drones Help Smallholder Farmers Improve Agriculture Efficiencies and Reduce Food Insecurity in Sub-Saharan Africa? Local Perceptions from Malawi

Smallholder farmers in sub-Saharan Africa play a vital role in achieving food security and nutrition, yet they are often overlooked by development policies and lack access to the technology and information needed to increase their agricultural productivity. This is particularly true in Malawi, where smallholder farmers make up over 80% of the population and face a range of risks and challenges, including vulnerability to climate change, that threaten their livelihoods, food security, and nutrition. While drones and precision agriculture technology have had a significant impact on agriculture in high-income countries, their application by smallholder farmers in low-income countries is not well understood. This study, conducted in 2022, examines how drones can assist smallholder farmers in increasing their agricultural productivity and food security in Malawi. It explores how smallholders perceive the use of drones and the potential benefits and limitations of using drones in their farming operations. A unique aspect of this study aims to understand smallholders’ perceptions of open data and data privacy. The results show that when smallholder farmers interact with drone data, they have a better understanding of their farm and are able to make more informed decisions that use fewer inputs and reduce production costs. Overall, this study demonstrates the potential for drones to assist smallholder farmers improve their on-farm knowledge, increase agricultural productivity, and mitigate the risks and challenges they face, leading to improved livelihoods and a more sustainable and secure food supply. Policymakers can promote the adoption of drone technology among smallholder farmers by developing policies that encourage public–private partnerships to create affordable, locally adapted drone technologies and programs that meet their unique needs, while also ensuring responsible use of drones in agriculture through regulations that address concerns about data privacy and security.

The influence of off-farm work on farm income among smallholder farm households in northern Ghana

Income diversification is an essential livelihood strategy among small-scale farmers in low-income countries. Through income diversification, farmers can potentially invest off-farm earnings into their farm business to enhance productivity and income from farming. Conversely, working off-farm can lead to a labour-loss effect which can reduce farm performance. This study therefore assesses the effect of off-farm work (OFW) on farm income using data from 486 smallholder farmers in northern Ghana. An endogenous treatment regression model was used to assess the effect of diversifying income sources on farm income. The results showed that involvement in OFW enhanced farm income per acre by GH¢ 386. Other factors that enhanced farm income included years of formal education and access to extension services and input subsidy. Farmer group membership and household size however reduced farm income. The farm sector can therefore take advantage of the positive linkage with the non-farm sector to improve farm income levels of farmers. In this light, government’s rural industrialization policy should seek to provide more job opportunities outside the farm sector to enable smallholder farmers to take advantage of such opportunities to improve income from on-farm activities.

A Climate Change Vulnerability Assessment Design Framework: The Case of Small-scale Farmers in Western Honduras

Climate change is now affecting every known society. Small-scale farmers in low-income countries are especially vulnerable to climate change because they depend heavily on rain, seasonality patterns, and known temperature ranges. Prioritizing the efforts of building climate change resilience and adaptive capacity for small-scale farmers is essential in achieving Sustainable Development Goals 13, 1, and 2. An important first step towards those efforts is to assess the climate change vulnerability among the population. We propose a Climate Change Vulnerability Assessment Framework Design Framework (CCVA-DF) to guide the design of innovative digital CCVA solutions to enhance the adaptive capacity and climate change resilience of small-scale farmers. The framework outlines modern methods for vulnerability data collection and processing through Remote Sensing and GIS, advanced spatial analysis and modeling for measuring vulnerabilities, and visual analytics to support decision-making in the planning and implementation of suitable interventions. The framework is instantiated into a web application that is used by a real-world organization for transforming household resilience in Western Honduras. The CCVA-DF showcases novel measures of vulnerability using geospatial technology. It provides guidelines to design digital vulnerability assessment tools that can be used by researchers and practitioners worldwide to tackle climate change challenges.

Role of inclusive market systems development in promoting resilience: evidence from World Vision projects

Evidence on whether market systems development (MSD) programmes for extremely poor smallholder farmers in low-income countries are associated with resilient outcomes when shocks/stressors appear is limited. We discuss the role of the inclusive MSD (iMSD) approach to generate resilience among vulnerable populations and report empirical evidence from World Vision’s project areas (with iMSD activities) and comparison communities in Tanzania and Rwanda. The panel data collected between 2017 and 2021 provide evidence on differences in household-level resilience in the face of COVID-19 shock. Descriptive estimates from the 2021 survey show project households had statistically greater food security, market participation, and perception of being fully/partially recovered than comparison households in both Tanzania and Rwanda. Integration in market systems helped buffer participants. Though food insecurity declined between survey rounds in Tanzania, it worsened in Rwanda, but more so among comparison households. Respondents in Rwanda experienced stricter COVID-19 ‘lockdowns’ and more limited iMSD activities than Tanzanians.

Animal manures and plant residue-based amendments for sustainable rice-wheat production and soil fertility improvement in eastern Uttar Pradesh, North India

Agroecological interventions are imperative for boosting agricultural productivity and soil fertility while increasing profitability of subsistence farmers in low-income countries by replacing synthetic fertilizers. With this context, the present study was aimed to evaluate the impact of animal manures (sheep and poultry manure) and plant residue-based organic amendments (rice husk biochar and sugarcane pressmud) on soil quality, nutrient uptake and balance, yield, and sustainability of rice-wheat cropping in alluvial (rainfed) and red lateritic soil (dryland) of middle Gangetic plains (Narayanpur) and Vindhyan region (Rajgarh) of Mirzapur district in eastern UP. The field experiments were conducted for three years at the above two sites and amendments were done at a rate by replacing 30% standard recommended doses of fertilizer (RDF) for rice-wheat cropping system. Field trials were conducted with the 100% RDF as control, and 70% RDF with sheep manure, poultry manure, rice-husk biochar and sugarcane pressmud in a randomized block design. The organic amendments were done during the rice cultivation stage and the residual effect was observed during the subsequent wheat cultivation. Though soil organic carbon (SOC) was found to show significant (p ≥ 0.05) increase in biochar amended plots, animal manures followed by pressmud showed year wise increase in both SOC and microbial biomass carbon. In rainfed areas, plant growth and yield attributes for both rice and wheat were at par in amendments than control while in dryland, the 100% RDF showed better performance during the first year, after that amended plot showed better performance. All amendments resulted in higher benefit: cost ratio except biochar addition in Narayanpur, whereas in Rajgarh, the poultry manure resulted in significant improvement in benefit: cost ratio from second year onward. Our study advocates that validation of suitable amendment packages based on organic inputs are imperative for improving the yield, soil quality and nutrient balance of rice-wheat cropping system and thereby attaining the UN-SDGs at the village/local level.

Recent pesticide exposure affects sleep: A cross-sectional study among smallholder farmers in Uganda.

Poorly educated smallholder farmers in low-income countries are highly exposed to pesticides. This can result in adverse mental health issues, of which sleep problems might be an underlying indicator. We aim to examine the association between sleep problems and pesticide exposure among smallholder farmers in Uganda. A cross-sectional survey with 253 smallholder farmers was conducted between October and December 2019. Sleep problems were assessed during the week before the visit using the Medical Outcomes Study Sleep Scale (MOS-SS). Exposure to pesticides was assessed as application days of any pesticide and as use of 2,4-D, glyphosate, mancozeb, organophosphates & carbamates, pyrethroids and other pesticides during the week and year prior to the visit. Associations were assessed using adjusted multivariable logistic regression models. Increased odds ratio (OR) for the sleep problem index 6-items (OR [95% Confidence Interval] 1.99 [1.04; 3.84] and 3.21 [1.33; 7.82]), sleep inadequacy (1.94 [1.04; 3.66] and 2.49 [1.05-6.22]) and snoring (3.17 [1.12; 9.41] and 4.07 [1.04; 15.14]) were observed for farmers who respectively applied pesticides up to two days and three or more days in the past week compared to farmers who did not apply during the past week. Gender-stratified analyses showed a higher OR for female applicators (4.27 [1.76-11.16]) than for male applicators (1.82 [0.91-3.79]) for the association between the sleep problem index 6-items and pesticide use in the week before the visit. Increased ORs were also observed for the association between the sleep problem index 6-item and mancozeb exposure during the past year 2.28 [1.12-4.71] and past week 2.51 [0.86-7.55] and glyphosate exposure during the past week 3.75 [1.24-11.8] compared to non-applicators. Our findings suggest an increased risk of sleep problems among smallholder farmers in a pesticide-exposure-dependent way in a low-income context. Further gender-stratified, longitudinal investigations are warranted to confirm these findings.

Valuing meteorological services in resource-constrained settings: Application to smallholder farmers in the Peruvian Altiplano

Changing climate and weather patterns have resulted in reduced agricultural productivity in some parts of the world and put pressure on global food security. Availability and improved quality of meteorological information is seen as a potentially propitious means of adaptation to changing climate conditions. Forecasts of extreme weather events are especially valuable in resource-poor settings where climate-related vulnerability is high, such as for smallholder farmers in low-income countries. In this paper we provide estimates of frost warnings valuation in the context of small-scale quinoa production in the Peruvian Altiplano using a cross-disciplinary approach. We first present a detailed contextual assessment of quinoa production in the study region based on agrometeorological and socio-economic data that was obtained through a representative farm household survey conducted in December 2016. Building on this assessment, we propose a stochastic life-cycle model, replicating the lifetime cycle of a quinoa-producing household, in order to derive a theoretical valuation of frost warnings. Calibrating the model to our data we provide estimates of frost-warning valuation which are in the range of $30–50 per household per year, depending on the forecast accuracy and agents’ risk aversion. In a last step, using the observational data from the farm household survey, we show that access to existing meteorological services is empirically associated with avoided losses in agricultural production that amount to $18 per average household and per year. Our findings point to high climate vulnerabilities of smallholders in the Peruvian Altiplano and potentially large welfare gains from incorporating improved meteorological services into their decision-making process. At the same time, we highlight that attention must also be paid to complementary non-meteorological interventions that bear the potential to leverage these welfare gains.

Between water stewardship and independent global water certification: learning from smallholder rice farmers, Karonga, Malawi

Cooperation and locally driven water management are at the forefront of food production water management for smallholder farmers in low-income countries. The aim of this paper was to critically reflect on the experiences of 5,819 smallholder rice farmers in Karonga District, Malawi, who were members of a farmers’ organization that achieved improved water stewardship, but could not achieve Alliance for Water Stewardship certification within a three-year project. The data for this paper were obtained through farmer and stakeholder interviews. The partnership attempted to bring together four parties: academics, farmers, local government, and a non-governmental organization. The farmers were trained by combining stewardship and certification topics through a train-the-trainer approach. The farmers’ organization primarily focuses on agribusiness; therefore, they did not have any water-related data or detailed farm boundaries from the large and dispersed group of farmers and could not obtain a collective water permit. Understanding water governance was difficult for many farmers. Furthermore, moving from stewardship to certification presented some financial challenges. Critical thinking and questioning are required, along with a deeper understanding of the local context, logistical hindrances, priorities, alternatives, culture, and science, to evaluate how projects are designed and partially succeed or fail from the perspective of low-income farmers in the Global South.

Exploring Sustainability Features and Determinants of Agricultural Insurance Programmes in Low-income Countries

Agriculture is the main occupation and source of livelihood for the majority of the inhabitants in low-income countries. However, agricultural activities in these countries are confronted with a plethora of challenges, including production and marketing risks. Some of the farmers in low-income countries have been employing autonomous and planned adaptation strategies, including agricultural insurance contracts to cope with the agricultural risks. Agricultural insurance has been acclaimed to possess enormous potential for managing agricultural risks in low-income countries. This study employed the literature review approach to identify the features and determinants of sustainable agricultural insurance programmes in low-income countries. The study found that the appropriate institutional arrangements, socio-economic and ecological pillars could interact to make agricultural insurance programmes in low-income countries sustainable. Since most low-income countries are still piloting and up scaling their agricultural insurance programmes, I recommend incorporating the institutional, socio-economic and ecological dimensions into the design and implementation of their agricultural insurance schemes.

Improved storage mitigates vulnerability to food-supply shocks in smallholder agriculture during the COVID-19 pandemic

Millions of smallholder farmers in low-income countries are highly vulnerable to food-supply shocks, and reducing this vulnerability remains challenging in view of climatic changes. Restrictions to limit the spread of the COVID-19 pandemic produced a severe supply-side shock in rural areas of Sub-Saharan Africa, including through frictions in agricultural markets. We use a large-scale field experiment to examine the effects of improved on-farm storage on household food security during COVID-19 restrictions. Based on text message survey data we find that the prevalence of food insecurity increased in control group households during COVID-19 restrictions (coinciding with the agricultural lean season). In treatment households, equipped with an improved on-farm storage technology and training in its use, food insecurity was lower during COVID-19 restrictions. This underscores the benefits of improved on-farm storage for mitigating vulnerability to food-supply shocks. These insights are relevant for the larger, long-term question of climate change adaptation, and also regarding trade-offs between public health protection and food security.

A simple, hand-held decision support designed tool to help resource-poor farmers improve potato late blight management

Many decision support systems (DSS) have been developed to manage potato late blight caused by Phytophthora infestans, but most of these require sophisticated equipment and are not realistic alternatives for small-scale farmers in low-income countries. This research evaluates a simple, hand-held decision support tool (HH-DST) consisting of a disk with three concentric circles, two of which represent factors that drive late blight epidemics and the third providing a spray recommendation. Three disks of different colors have been designed for potato varieties of varying levels of host resistance. The HH-DST was compared with locally used fungicide spray regimes in three trials in Peru, and in six trials in Ecuador, where the tool had been slightly modified. In two additional trials in Peru, the HH-DST was compared with local practices, calendar spraying and two other DSS. The HH-DST and local spray regimes both gave relatively good disease control in all cases, however, the HH-DST was more effective with highly susceptible cultivars both in Ecuador and Peru. The HH-DST also had equal or lower number of sprays per season and had a lower environmental impact, based on the environmental impact quotient (EIQ), than did the local practices. Results were similar in trials comparing different DSS, where all approaches, including the HH-DST, adequately controlled disease, and the HH-DST was among the lowest for both number of sprays per season and environmental impact. The HH-DST is a simple tool that can help resource-poor farmers improve management of potato late blight.

Plant resistance inducers (PRIs): perspectives for future disease management in the field.

Abstract Plants are confronted with numerous biotic stresses that may affect productivity. Besides their constitutive defence, plants can activate specific metabolic processes to enhance resistance upon stress detection. These defence mechanisms can also be activated through the recognition of plant resistance inducers (PRIs). This review highlights some of the current challenges that prevent the adoption of PRIs in agriculture, and explore research topics and knowledge gaps to be addressed for bringing PRIs closer to practice. First, we present studies on the variance of induced defence responses and examine the possibility of employing inducibility in breeding strategies as well as the possible role of epigenetics. We also discuss the efficiency of PRIs in future climate and knowledge gaps on this subject. Remote sensing, high-throughput phenotyping and modelling in combination with PRIs as part of decision support systems and integrated pest management are further possibilities to advance the use of PRIs. Finally, we discuss the challenges which need to be addressed to make PRIs available for small-scale farmers in low-income countries. Although PRIs have successfully presented significant rates of disease prevention under controlled conditions, converting these findings into field application still depends on more studies, e.g. on how they can be integrated into disease management programmes. Better mechanistic understanding of IR together with the coupling of PRIs to new disease monitoring and protection strategies can give PRIs a stronger role in future agricultural practice.

Realizing the potential of digital development: The case of agricultural advice.

The rapid spread of mobile phones creates potential for sustainably raising agricultural productivity for the 2 billion people living in smallholder farming households. Meta-analyses suggest that providing agricultural information via digital technologies increased yields by 4% and the odds of adopting recommended inputs by 22%. Benefits likely exceed the cost of information transmission by an order of magnitude. The spread of GPS-enabled smartphones could increase these benefits by enabling customized information, thus incentivizing farmers to contribute information to the system. Well-known distortions in markets for information limit the ability of such systems to reach the socially efficient scale through purely commercial means. There is a clear role for public support for digital agricultural extension, but messages designed by agricultural ministries are often difficult for farmers to understand and use. Realizing the potential of mobile communication systems requires feedback mechanisms to enable rigorous testing and continuous improvement.

Mobile farming advice

Agriculture Mobile phones are almost universally available, and the costs of information transmission are low. They are used by smallholder farmers in low-income countries, largely successfully, to optimize markets for their produce. Fabregas et al. review the potential for boosting mobile phone use with smartphones to deliver not only market information but also more sophisticated agricultural extension advice. GPS-linked smartphones could provide locally relevant weather and pest information and video-based farming advice. But how to support the financial requirements of such extension services is less obvious, given the unwieldiness of government agencies and the vested interests of commercial suppliers. Science , this issue p. [eaay3038][1] [1]: /lookup/doi/10.1126/science.aay3038