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Predicting the consequences of manipulating genotype (G) and agronomic management (M) on agricultural ecosystem performances under future environmental (E) conditions remains a challenge. Crop modelling has the potential to enable society to assess the efficacy of G × M technologies to mitigate and adapt crop production systems to climate change. Despite recent achievements, dedicated research to develop and improve modelling capabilities from gene to global scales is needed to provide guidance on designing G × M adaptation strategies with full consideration of their impacts on both crop productivity and ecosystem sustainability under varying climatic conditions. Opportunities to advance the multiscale crop modelling framework include representing crop genetic traits, interfacing crop models with large-scale models, improving the representation of physiological responses to climate change and management practices, closing data gaps and harnessing multisource data to improve model predictability and enable identification of emergent relationships. A fundamental challenge in multiscale prediction is the balance between process details required to assess the intervention and predictability of the system at the scales feasible to measure the impact. An advanced multiscale crop modelling framework will enable a gene-to-farm design of resilient and sustainable crop production systems under a changing climate at regional-to-global scales.

Food systems are increasingly challenged to meet growing demand for specialty crops due to the effects of climate change and increased competition for resources. Here, we apply an integrated methodology that includes climate, crop, economic and life cycle assessment models to US potato and tomato supply chains. We find that supply chains for two popular processed products in the United States, French fries and pasta sauce, will be remarkably resilient, through planting adaptation strategies that avoid higher temperatures. Land and water footprints will decline over time due to higher yields, and greenhouse gas emissions can be mitigated by waste reduction and process modification. Our integrated methodology can be applied to other crops, health-based consumer scenarios (fresh versus processed) and geographies, thereby informing decision-making throughout supply chains. Employing such methods will be essential as food systems are forced to adapt and transform to become carbon neutral due to the imperatives of climate change. An integrated methodology that includes climate, crop, economic and life cycle assessment models was developed to explore the climate adaptation and mitigation opportunities throughout the US potato and tomato supply chains. This study shows that supply chains for two popular processed products in the United States, French fries and pasta sauce, will be remarkably resilient, through planting adaptation strategies.

Food systems are increasingly challenged to meet growing demand for specialty crops due to the effects of climate change and increased competition for resources. We apply a novel integrated methodology that includes climate, crop, economic, and life cycle assessment (LCA) models to US potato and tomato supply chains. We assess the effectiveness of changing management strategies to address climate change and the opportunity to relocate away from regions with increased water scarcity. We find that supply chains for two popular processed products in the United States, French fries and pasta sauce, will be remarkably resilient, through planting adaptation strategies that avoid higher temperatures. Land and water footprints will decline over time due to higher yields, and GHG emissions can be mitigated by waste reduction and process modification. Our integrated methodology can be applied to other crops and geographies, and the results could inform decision-making at multiple steps along supply chains.

Twenty-first-century challenges for food and nutrition security include the spread of obesity worldwide and persistent undernutrition in vulnerable populations, along with continued micronutrient deficiencies. Climate change, increasing incomes and evolving diets complicate the search for sustainable solutions. Projecting to the year 2050, we explore future macronutrient and micronutrient adequacy with combined biophysical and socioeconomic scenarios that are country-specific. In all scenarios for 2050, the average benefits of widely shared economic growth, if achieved, are much greater than the modelled negative effects of climate change. Average macronutrient availability in 2050 at the country level appears adequate in all but the poorest countries. Many regions, however, will continue to have critical micronutrient inadequacies. Climate change alters micronutrient availability in some regions more than others. These findings indicate that the greatest food security challenge in 2050 will be providing nutritious diets rather than adequate calories. Research priorities and policies should emphasize nutritional quality by increasing availability and affordability of nutrient-dense foods and improving dietary diversity. Global environmental change complicates the goal of securing adequate nutrition for a growing world population. This study assesses the per capita availability of food nutrients for various scenarios to the year 2050. Results suggest that economic growth will expand food and macronutrient access more than climate change will suppress it, but that micronutrient inadequacies will plague some regions.

Recent analyses indicate that global fruit and vegetable (F&V) production will need to increase by 50%–150% by 2050 in order to achieve sustainable and healthy diets for 10 billion people. Although global production of F&V has grown by 50% during the last two decades alone, simply scaling up current systems of F&V production, supply chains, and consumption will inevitably worsen environmental and socioeconomic tradeoffs. This article examines three examples of important F&V—avocados, leafy greens, and tomatoes—to assess the global challenge of meeting dietary recommendations at affordable prices to consumers while sustaining producer livelihoods and minimizing environmental damage. These three cases highlight key characteristics of F&V systems that make the challenge of sustainable expansion especially difficult: knowledge-, input-, and labor-intensive production, high rates of food loss and waste, and low affordability to consumers relative to less nutrient-dense food groups. Our analysis shows that only by investing in innovations that increase diversity, integrate technology, and improve equity will truly sustainable expansion of F&V systems be possible.

We’re being warned of future grain failures—not by the dreams of a biblical Pharaoh, but by modern computer model predictions. Climate science forecasts rising temperatures, changing rainfall patterns, and episodes of increasingly extreme weather, which will harm crop yields at a time when the world’s growing population can ill afford declines, especially in its most productive areas, such as the US Midwest. In order to adequately prepare, we call for the establishment of a new field research network across the US Midwest to fully integrate all methods for improving cropping systems and leveraging big data (agronomic, economic, environmental, and genomic) to facilitate adaptation and mitigation. Such a network, placed in one of the most important grain-producing areas in the world, would provide the set of experimental facilities, linked to farm settings, needed to explore and test the adaptation and mitigation strategies that already are needed globally.

Nutrition science-based dietary advice urges changes that may have a great impact on agricultural systems. For example, the 2016 Dietary Guidelines for Americans (DGA) recommends greatly increased fruit and vegetable consumption, but the present domestic production is insufficient to accommodate large-scale adoption of these guidelines. Increasing production to the extent needed to meet the DGA will necessitate changes in an already stressed agriculture and food system and will require nutrition and agriculture professionals to come together in open and collegial discourse. All involved need to understand the stress placed on the food system by increasing populations, changing diets, and changing environments, and recognize the major diet-based public health challenges. Furthermore, there is a need to understand the intricate interplay of the myriad parts of the food system and the vast amount of work necessary to make even small changes. New systems approaches are needed, especially at the research level, where nutrition, public health, agriculture, and the food industry work together to solve interconnected problems. Future well-being depends on a sustainable food system that continues to deliver optimal health with minimal impact on the environment.

The literature on the importance of plant pathogens sometimes emphasizes their possible role in historical foodshortages and even in famines. Aside from such major crises, plant pathogens should also be seen as important reducers of crop performances, with impacts on system sustainability, from the ecological, agronomical, social, and economic standpoints – all contributing ultimately to affecting food security. These views need reconciliation in order to produce a clearer picture of the multidimensional effects of plant disease epidemics. Such a picture is needed for disease management today, but would also be useful for future policies. This article attempts to develop a framework that would enable assessment of the impacts of plant diseases, referred collectively to as crop health, on food security via its components. We have combined three different existing definitions of food security in order to develop a framework consisting of the following six components: (1) Availability. Primary production; (2) Availability. Import - Stockpiles; (3) Access. Physical and supply chain; (4) Access. Economic; (5) Stability of food availability; (6) Utility-Safety-Quality- Nutritive value. In this framework, components of food security are combined with three attributes of production situations: the nature of the considered crop (i.e. food- or non- food), the structure of farms (i.e. subsistence or commercial), and the structure of markets (i.e. weakly organized and local, to strongly organized and globalized). The resulting matrix: [Food security components] × [Attributes of production situations] provides a framework where the impacts of chronic, acute, and emerging plant disease epidemics on food security can be examined. We propose that, given the number of components and interactions at play, a systems modelling approach is required to address the functioning of food systems exposed to plant disease risks. This approach would have application in both the management of the current attrition of crop performances by plant diseases, and also of possible disease-induced shocks. Such an approach would also enable quantifying shifts in disease vulnerability of production situations, and therefore, of food systems, as a result of climate change, globalization, and evolving crop health.

Sustainability considerations should be an integral component of food security assessments. Nourishing the expected global population of nine billion in the face of fast diminishing land and water resources and looming climate change has tremendous economic, environmental, and social implications. Furthermore, whereas much past work on food security had focused on feeding the world through more staple crop calories, the current emphasis is on nourishing the global population through the provision of a more nutrient-rich diet. Hence the focus on micronutrient deficiencies (so-called ‘hidden hunger’), dietary diversity, and the nutrient density of the food supply—all critical components of overall nutritional status. To aid future assessments of ‘sustainable nutrition security’, we need a new methodology and some novel assessment metrics and tools. Seven metrics are proposed, each based on a combination of multiple indicators, for use in characterizing sustainable nutrition outcomes of food systems: (1) nutrient adequacy of foods and diets; (2) ecosystem stability; (3) food affordability and availability; (4) sociocultural wellbeing; (5) food safety; (6) resilience; and (7) waste and loss reduction. Each of the metrics comprises multiple indicators that are combined to derive an overall score (0–100). The metrics can be combined with simulation models and then deployed by decision-makers and investors to set meaningful goals, track progress, and evaluate the potential impact of targeted food system interventions. The goal is to improve food system sustainability and resilience and to improve human nutrition and health outcomes.

A session was convened at the ASN Nutrition 2018 annual meeting to discuss the scientific evidence on what makes individual foods and dietary patterns both sustainable and nutritious, and the role of various stakeholders in the actions needed to implement food systems that deliver “sustainable nutrition.” This commentary is a structured synthesis of the primary themes of the session, and concludes with a set of implications and research recommendations. Consumers are becoming increasingly aware of the environmental implications of what they eat, and there is growing momentum toward changes in the food system. However, ecological challenges persist, and although the literature is evolving, methodologic improvements are needed in the scientific approaches to address dietary patterns that meet nutrition needs in more holistically sustainable ways. The session concluded with encouraging evidence that consumers, businesses, scientists, and policy-makers are collectively “rising to the occasion,” with cross-sectoral partnerships to address these issues.

Sustainability considerations have been absent from most food security assessments conducted to date, despite the tremendous economic, environmental, and social implications of meeting accelerating food demand in the face of water shortages and climate change. In addition, previous food security work has generally focused only on achieving adequate calories, rather than addressing dietary diversity and micronutrient adequacy, both of which are critical to maintaining a healthy overall nutritional status. In response to the limitations of previous assessments, a new methodology is proposed here based on the concept of “sustainable nutrition security” (SNS). This novel assessment methodology is intended to remedy both kinds of deficiencies in the previous work by defining seven metrics, each based on a combination of multiple indicators, for use in characterizing sustainable nutrition outcomes of food systems: (1) food nutrient adequacy; (2) ecosystem stability; (3) food affordability and availability; (4) sociocultural wellbeing; (5) food safety; (6) resilience; and (7) waste and loss reduction. Each of the metrics comprises multiple indicators that are combined to derive an overall score (0–100). A novel SNS assessment methodology based on these metrics can be deployed by decision-makers and investors to set meaningful goals, track progress, and evaluate the potential impact of food system interventions intended to improve sustainability and human nutrition outcomes.

Convincing data now show that temperatures are increasing, and that changing precipitation patterns are already affecting agriculture. Predicted future impacts vary by region, but all are projected to suffer productivity declines by the late twenty-first century unless successful mitigation measures are implemented soon. Exacerbating the climate change challenge, doubling of overall crop productivity will be required by mid-century. Clearly, crop protection will become increasingly difficult as higher-yielding varieties present a larger and more tempting target to all pests, and the pests themselves extend their ranges poleward and into other new geographies owing to reduced winter kill and longer growing seasons. Fortunately, good progress on enhancing crop protection technology to meet these challenges is already being made, but the scope of this climatic provocation is such that complacency is not an option. Increased investment into new technologies and adoption of new agricultural practices with improved adaptive and mitigation potential are both essential. Copyright © 2011 Society of Chemical Industry

DiGiovanni and Kevan (2008, Environ. Biosafety Res. 7 : 105–108) commented extensively on the empirical approach that I and my co-authors took in our previous modeling of pollen-mediated gene flow in maize (Gustafson et al. (2006) Crop Sci. 46 : 2133–2140). As we detailed in that original paper, gene flow is a highly complex process that necessarily requires at least some level of empiricism in order to adequately quantify all of the biological, meteorological, and physical phenomena that are involved. DiGiovanni and Kevan favor a mechanistic modeling approach, and they proposed a number of potential advantages for such a method over our entirely empirical technique. However, the 20 m buffers we had proposed based on our empirical model continue to be supported by the rapidly growing body of experimental data on maize gene flow that has now been collected in Europe and elsewhere around the world. This does not mean there is no place for mechanistic modeling of gene flow, but it does suggest that properly implemented empirical approaches have a valid role to play. They offer a degree of simplicity and practical utility that is not available from more complicated approaches.

Agreement is developing among agricultural scientists on the emerging inability of agriculture to meet growing global food demands. The lack of additional arable land and availability of freshwater have long been constraints on agriculture. However, the increased frequency of extreme and unpredictable weather events, in a manner consistent with the changes predicted by global climate models, is expected to exacerbate the global food challenge as we move toward the middle of the 21st century. These climate- and constraint-driven crop production challenges are interconnected within a complex global economy, where diverse factors add to price volatility and food scarcity. The present report projects the impact of climate change on food security through the year 2050. The analysis presented here suggests that climate change in the first half of the 21st century does not represent a near-term threat to food security in the US due to the availability of adaptation strategies. However, as climate continues to trend away from 20th century norms current adaptation measures will not be sufficient to enable agriculture to meet growing food demand. High-end projections on carbon emissions will exacerbate the food shortfall, although uncertainty in climate model projections (particularly precipitation) is a limitation to impact studies.

Roundup Ready (glyphosate-resistant) cropping systems enable the use of glyphosate, a non-selective herbicide that offers growers several benefits, including superior weed control, flexibility in weed control timing and economic advantages. The rapid adoption of such crops in North America has resulted in greater glyphosate use and concern over the potential for weed resistance to erode the sustainability of its efficacy. Computer modeling is one method that can be used to explore the sustainability of glyphosate when used in glyphosate-resistant cropping systems. Field tests should help strengthen the assumptions on which the models are based, and have been initiated for this purpose. Empirical evaluations of published data show that glyphosate-resistant weeds have an appearance rate of 0.007, defined as the number of newly resistant species per million acres treated, which ranks low among herbicides used in North America. Modeling calculations and ongoing field tests support a practical recommendation for growers occasionally to include other herbicides in glyphosate-resistant cropping systems, to lower further the potential for new resistance to occur. The presented data suggest that the sustainability of glyphosate in North America would be enhanced by prudent use of additional herbicides in glyphosate-resistant cropping systems.

The article by Swan et al. (2003) suggested that alachlor exposure was linked to reduced sperm quality in fertile men; after publication of the article, Monsanto (St. Louis, MO) began a detailed examination of the issue because the findings were entirely unexpected and inconsistent with both our information and the extensive published literature on alachlor. Most surprisingly, alachlor mercapturate (AM) was reportedly found in the urine of 92% of study participants in Columbia, Missouri. Because this metabolite arises exclusively from exposure to the parent compound, few, if any, detects would be expected based on declining alachlor use (National Agricultural Statistics Service 2005) and our detailed understanding of its biological and environmental properties (Feng et al. 1994). Also, extensive water monitoring studies submitted to the U.S. Environmental Protection Agency (EPA) have shown that parent alachlor occurs very infrequently in both potable wells (Holden et al. 1992) and drinking water from surface water sources (Hackett et al. 2005), thereby calling into question the plausibility of such widespread exposure. We met with Swan and colleagues at the University of Missouri in Columbia (UMC), and with the personnel at the Centers for Disease Control and Prevention (CDC) who conducted the analyses, to discuss our surprise at the findings. Our concern about the reported frequent detections of alachlor in urine was heightened when we learned that the liquid chromatography/mass spectrometry–mass spectrometry method employed by the CDC (Olsson et al. 2004) included no confirmatory ions, a standard technique for avoiding false positives in the analysis of urine (Department of Health and Human Services 1998). An 18-month collaboration ensued, which included numerous discussions and a round-robin study conducted between Monsanto and the CDC, with involvement by UMC researchers, to assess the performance and transferability of the methods used by each laboratory. After successful completion of the round-robin study, several frozen urine samples retained from the original study were sent to Monsanto. In results that we intend to submit for publication, we found no detectable level of AM (limit of detection < 0.10 ppb) in samples that the CDC reported to contain up to 3 ppb (Swan et al. 2003). Sample degradation does not explain this difference, because we have data demonstrating AM stability under such conditions. Our analyses followed Good Laboratory Practice standards [U.S. Environmental Protection Agency (EPA) 1989] and included confirmatory ions. We also analyzed urine samples of 52 volunteers from agricultural areas across North America, none of which actually contained detectable AM, but 11 of which showed false positives when confirmatory ions were not used. The CDC has now modified its method to include confirmatory ions for alachlor. We are confident that little or no AM would have been detected had they included confirmatory ions in the original analysis. The CDC previously declined Monsanto's request that they analyze the original samples using a modified method with confirmatory ions. However, after receiving an earlier version of this letter, the CDC quickly performed new analyses of 14 retained frozen samples and informed us that analysis with confirmatory ions validated their original findings. Unfortunately, the CDC has not provided us with sufficient data to confirm the validity of the new method and results. Monsanto continues to believe the detections are spurious. From our perspective, the only possible resolution of the matter at this time would be for the retained samples to be sent to an independent third-party laboratory for confirmatory analysis. We understand Swan et al. are now having urine samples from other similar agricultural areas analyzed using a confirmatory method, and that AM is no longer being routinely detected. This would affirm that alachlor exposure is rare and the alleged link to semen quality is implausible. It would be very informative to identify the apparent interferent using high-resolution mass spectrometry methodology, but our collaboration has clearly shown that it was not AM. The evidence presented by our analyses of the samples provided by Swan, supported by our successful performance in the round-robin analysis of fortified samples, demonstrates that the reported detections of alachlor were most likely attributable to an interferent. The data refute any link between alachlor exposure and reduced sperm quality in fertile men.

Biomonitoring was used to assess the combined dermal, oral, and inhalation exposure associated with the agricultural use of Harness Plus, an emulsifiable concentrate formulation of the herbicide acetochlor. Twenty Spanish farmers handled and applied acetochlor to maize in the spring of 2003, following the product label recommendations. Open- and closed-cabin applications were equally represented. Urine was collected during six consecutive days, starting the day prior to application. Daily composites were analyzed for 2-ethyl-6-methyl-aniline, a common chemophore representing the major urinary acetochlor metabolites. All applicators showed detectable concentrations in urine after application. Although, the open-cabin applicators treated fewer hectares, they showed significantly higher exposure compared to the closed-cabin applicators (average exposure: 0.004 and 0.002 mg/kg bw/day, respectively). Linear regression analysis suggested that untracked incidents had a significant impact on the total exposure. Other events that may have contributed to the observed exposure are repair of faulty equipment, accidental spillages, splashes, and inadequate use of protective gloves. The average margins of exposure (MOE) for farmers ranged from 23,000 (open cabin) to about 44,000 (closed cabin). For professional applicators the MOEs were 10-fold lower. These MOEs clearly indicate that no adverse health effects should be expected from agricultural acetochlor applications.

An updated empirical approach is proposed for specifying coexistence requirements for geneti- cally modified (GM) maize ( Zea mays L.) produc- tion to ensure compliance with the 0.9% label- ing threshold for food and feed in the European Union. The model improves on a previously published (Gustafson et al., 2006) empirical model by adding recent data sources to supple- ment the original database and including the fol- lowing additional cases: (i) more than one GM maize source field adjacent to the conventional or organic field, (ii) the possibility of so-called "stacked" varieties with more than one GM trait, and (iii) lower pollen shed in the non-GM recep- tor field. These additional factors lead to the possibility for somewhat wider combinations of isolation distance and border rows than required in the original version of the empirical model. For instance, in the very conservative case of a 1-ha square non-GM maize field surrounded on all four sides by homozygous GM maize with 12 m isolation (the effective isolation distance for a single GM field), non-GM border rows of 12 m are required to be 95% confident of gene flow less than 0.9% in the non-GM field (with adventi - tious presence of 0.3%). Stacked traits of higher GM mass fraction and receptor fields of lower pollen shed would require a greater number of border rows to comply with the 0.9% threshold, and an updated extension to the model is pro- vided to quantify these effects.

Surveys of drinking water quality throughout the agricultural regions of the world have revealed the tendency of certain crop protection chemicals to enter water supplies. Fortunately, the trace concentrations that have been detected are generally well below the levels thought to have any negative impact on human health or the environment. However, the public expects drinking water to be pristine and seems willing to bear the costs involved in further regulating agricultural chemical use in such a way so as to eliminate the potential for such materials to occur at any detectable level. Of all the tools available to assess exposure to agricultural chemicals via drinking water, computer models are one of the most cost-effective. Although not sufficiently predictive to be used in the absence of any field data, such computer programs can be used with some degree of certainty to perform quantitative extrapolations and thereby quantify regional exposure from field-scale monitoring information. Specific models and modeling techniques will be discussed for performing such exposure analyses. Improvements in computer technology have recently made it practical to use Monte Carlo and other probabilistic techniques as a routine tool for estimating human exposure. Such methods make it possible, at least in principle, to prepare exposure estimates with known confidence intervals and sufficient statistical validity to be used in the regulatory management of agricultural chemicals.

Agricultural chemicals sporadically occur at detectable levels in the surface waters of intensively farmed watersheds. HSPF, a previously released model of agricultural chemicals in surface water, had been used to predict concentrations which were much higher (10 X) than those actually observed during monitoring studies. A new model, SURFACE, is described here which is much simpler than HSPF and gives better predictions of surface water concentrations. SURFACE uses PRZM, an EPA model, to calculate edge‐of‐field runoff losses and simple hydraulic routing algorithms to determine concentrations at the bottom of large river basins. In water systems sampled during 1985 and 1986, SURFACE predictions of annualized mean concentrations for alachlor, atrazine, cyanazine and metolachlor were within 0.09 ppb half of the time.

Reforestation efforts throughout the world are often hindered by animal browse damage. Numerous harmful natural phenomena affect seedling growth, including nutrient deficiencies, competing vegetation, insects, disease, and drought. However, animal damage is often found to have the most severely deleterious effects on the tree. Loss of time in reestablishing trees on harvested sites can necessitate costly replanting practices. The financial incentive for protecting seedlings has led to the development of several mechanical and chemical repellent systems.