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Science attempts to be a meritocracy; however, in recent years, there has been increasing evidence for systematic gender bias against women. This bias is present in many metrics commonly used to evaluate scientific productivity, which in turn influences hiring and career success. Here we explore a new metric, the Altmetric Attention Score, and find no evidence of bias across many major journals (Nature, PNAS, PLOS One, New England Journal of Medicine, Cell, and BioRxiv), with equal attention afforded to articles authored by men and women alike. The exception to this rule is the journal Science, which has marked gender bias against women in 2018, equivalent to a mean of 88 more tweets or 11 more news articles and a median of 20 more tweets or 3 more news articles for male than female first authors. Our findings qualify Altmetric, for many types and disciplines of journals, as a potentially unbiased measure of science communication in academia and suggest that new technologies, such as those on which Altmetric is based, might help to democratize academic evaluation.

Sweet potato (Ipomoea batatas [L.] Lam.) is one of the most important staple crops globally with particular cultural and economic significance in the Hawaiian Islands, yet the extent to which traditional cultivars persist remains unknown. The objective of this study was to elucidate the relationships between traditional Hawaiian sweet potato varieties and cultivars that originated elsewhere in the world. We sought to characterize genetic and phenotypic diversity of sweet potatoes represented in the Hawaiian Islands. To this end, a genetic assignment analysis was conducted on a sample of 77 individuals that consisted of traditional Hawaiian, USDA NPGS accessions, and recent herbarium samples. Additionally, voucher specimens of Hawaiian cultivars from the early twentieth century were assessed for variation in leaf morphology. We identified several inconsistencies within the Hawaiian-named varieties, as identically named varieties turned out to be genetically distinct, and similarly named voucher specimens varied in leaf morphology. Our findings call attention to the value of a set of Hawaiian sweet potatoes as “heirloom.” These genetically distinct traditional cultivars have unique value in local markets and present an opportunity to increase cultivar diversity in the markets and fields, support farmer income and diversified agriculture, all while contributing to reinvigoration of Hawaiian cultural heritage.

Adopting modern gene-editing technologies for trait improvement in agriculture requires important workflow developments, yet these developments are not often discussed. Using tropical crop systems as a case study, we describe a workflow broken down into discrete processes with specific steps and decision points that allow for the practical application of the CRISPR-Cas gene editing platform in a crop of interest. While we present the steps of developing genome-edited plants as sequential, in practice parts can be done in parallel, which are discussed in this perspective. The main processes include 1) understanding the genetic basis of the trait along with having the crop’s genome sequence, 2) testing and optimization of the editing reagents, development of efficient 3) tissue culture and 4) transformation methods, and 5) screening methods to identify edited events with commercial potential. Our goal in this perspective is to help any lab that wishes to implement this powerful, easy-to-use tool in their pipeline, thus aiming to democratize the technology.

Societal Impact Statement Plant breeding is crucial for improving agricultural crops for human use. However, an urgent rethink is needed to ensure the next generation of plant breeders have the necessary breadth of skills to provide ever more efficient, nutritious, profitable, and environmentally sustainable crops. Plant breeding is a multifaceted endeavor, which intersects with many other disciplines and professions. To help ensure that future plant breeding efforts are sustainable and relevant to the needs of society, it is vital that the interdisciplinary nature of the plant breeding profession is adequately reflected in student training and development. Summary Breeders need to have many faces to understand not only genetics but also environmental, social, and economic factors that are relevant for maintaining or improving crops for human use. In the United States, there is a long history of public involvement in agriculture and plant breeding. However, recent changes in the social systems underpinning public agriculture (i.e., funding structure) necessitate a rethinking of how agriculture education, specifically plant breeding education, should be facilitated. To provide viable plant breeding programs, it is necessary to explicitly acknowledge that breeding has been an interdisciplinary, long‐standing public endeavor to increase food system stability. Acknowledging this complexity has important pedagogical implications: the core of plant breeding resides in genetics, but the changing nature of this profession requires breeders to embrace a much broader training. Here, we suggest specific curricular objectives for plant breeders.

Plant breeding has been central to global increases in crop yields. Breeding deserves praise for helping to establish better food security, but also shares the responsibility of unintended consequences. Much work has been done describing alternative agricultural systems that seek to alleviate these externalities, however, breeding methods and breeding programs have largely not focused on these systems. Here we explore breeding and selection strategies that better align with these more diverse spatial and temporal agricultural systems. Published version

Global climate change is having a significant effect on agriculture by causing greater precipitation variability and an increased risk of drought. To mitigate these effects, it is important to identify specific traits, adaptations, and germplasm that improve tolerance to soil water deficit. Local varieties, known as landraces, have undergone generations of farmer-mediated selection and can serve as sources of variation, specifically for tolerance to abiotic stress. Landraces can possess local adaptations, where accessions adapted to a particular environment will outperform others grown under the same conditions. We explore adaptations to water deficit in chile pepper landraces from across an environmental gradient in Mexico, a center of crop domestication and diversity, as well in improved varieties bred for the US. In the present study, we evaluated 25 US and Mexico accessions in a greenhouse experiment under well-watered and water deficit conditions and measured morphological, physiological, and agronomic traits. Accession and irrigation regime influenced biomass and height, while branching, CO2 assimilation, and fruit weight were all influenced by an interaction between accession and irrigation. A priori group contrasts revealed possible adaptations to water deficit for primary branching, CO2 assimilation, and plant height associated with geographic origin, domestication level, and pepper species. Additionally, within the Mexican landraces, the number of primary branches had a strong relationship with precipitation from the environment of origin. This work provides insight into chile pepper response to water deficit and adaptation to drought and identifies possibly tolerant germplasm.

Improved nitrogen (N) use is key to future food security and environmental sustainability. While many regions still experience N shortages, agriculture is the leading global emitter of N2O due to losses exacerbated by N surpluses in other regions. In order to sustainably maintain or increase food production, farmers and their advisors need a comprehensive and actionable understanding of how nutrient management affects both yield and N2O emissions, particularly in tropical and subtropical agroecosystems. We performed a meta‐analysis to determine the effect of N management and other factors on N2O emissions, plant N uptake, and yield. Our analysis demonstrates that performance indicators—partial N balance and partial factor productivity—predicted N2O emissions as well as or better than N rate. While we observed consistent production and environmental benefits with enhanced‐efficiency fertilizers, we noted potential trade‐offs between yield and N2O emissions for fertilizer placement. Furthermore, we observed confounding effects due to management dynamics that co‐vary with nutrient application practices, thus challenging the interpretation of the effect of specific practices such as fertilization frequency. Therefore, rather than providing universally prescriptive management for N2O emission reduction, our evidence supports mitigation strategies based upon tailored nutrient management approaches that keep N balances within safe limits, so as to minimize N2O emissions while still achieving high crop yields. The limited evidence available suggests that these relationships hold for temperate, tropical, and subtropical regions, but given the potential for expansion of N use in crop production, further N2O data collection should be prioritized in under‐represented regions such as Sub‐Saharan Africa., Our findings show that, unlike many soil and climate variables, fertilizer management had consistent impacts on crop yields and N2O emissions with potential synergies and trade‐offs. Our evidence supports mitigation strategies based upon tailored nutrient management approaches that keep N balances within safe limits, so as to minimize N2O emissions while still achieving high crop yields. Practices that enhance partial factor productivity of N can result in lower N2O emissions for a given level of productivity and “shift” the exponential increase in N2O emissions as productivity increases.

The diversity observed among crop wild relatives and their ability to flourish in unfavorable and harsh environments have drawn the attention of plant scientists and breeders for many decades. However, it is also recognized that the benefit gained from using crop wild relatives in breeding is a potential rose between thorns of detrimental genetic variation that is linked to the trait of interest. Despite the increased interest in crop wild relatives, little attention was given so far to the statistical, analytical, and technical considerations that should guide the sampling design, the germplasm characterization, and later its implementation in breeding. Here, we review the entire process of sampling and identifying beneficial genetic variation in crop wild relatives and the challenge of using it in breeding. The ability to detect beneficial genetic variation in crop wild relatives is strongly affected by the sampling design which should be adjusted to the spatial and temporal variation of the target species, the trait of interest, and the analytical approach used. Moreover, linkage disequilibrium is a key factor that constrains the resolution of searching for beneficial alleles along the genome, and later, the ability to deplete linked deleterious genetic variation as a consequence of genetic drag. We also discuss how technological advances in genomics, phenomics, biotechnology, and data science can improve the ability to identify beneficial genetic variation in crop wild relatives and to exploit it in strive for higher-yielding and sustainable crops.

Cover cropping is considered a cornerstone practice in sustainable agriculture; however, little attention has been paid to the cover crop production supply chain. In this Perspective, we estimate land use requirements to supply the United States maize production area with cover crop seed, finding that across 18 cover crops, on average 3.8% (median 2.0%) of current production area would be required, with the popular cover crops rye and hairy vetch requiring as much as 4.5% and 11.9%, respectively. The latter land requirement is comparable to the annual amount of maize grain lost to disease in the U.S. We highlight avenues for reducing these high land use costs., In this Perspective, Bryan Runck and colleagues discuss an often-overlooked consequence of scaling up cover cropping – a cornerstone of sustainable agriculture. Using published seed yield data from common cover crops, they demonstrate the potentially large land use cost and discuss ways for reducing this cost.

Bitcoin is a power-hungry cryptocurrency that is increasingly used as an investment and payment system. Here we show that projected Bitcoin usage, should it follow the rate of adoption of other broadly adopted technologies, could alone produce enough CO2 emissions to push warming above 2 °C within less than three decades.

Graphics are becoming increasingly important for scientists to effectively communicate their findings to broad audiences, but most researchers lack expertise in visual media. We suggest collaboration between scientists and graphic designers as a way forward and discuss the results of a pilot project to test this type of collaboration.

In the interest of diversifying the global food system, improving human nutrition, and making agriculture more sustainable, there have been many proposals to domesticate wild plants or complete the domestication of semidomesticated orphan crops. However, very few new crops have recently been fully domesticated. Many wild plants have traits limiting their production or consumption that could be costly and slow to change. Others may have fortuitous preadaptations that make them easier to develop or feasible as high-value, albeit low-yielding, crops. To increase success in contemporary domestication of new crops, we propose a pipeline approach, with attrition expected as species advance through the pipeline. We list criteria for ranking domestication candidates to help enrich the starting pool with more preadapted, promising species. We also discuss strategies for prioritizing initial research efforts once the candidates have been selected: developing higher value products and services from the crop, increasing yield potential, and focusing on overcoming undesirable traits. Finally, we present new-crop case studies that demonstrate that wild species’ limitations and potential (in agronomic culture, shattering, seed size, harvest, cleaning, hybridization, etc.) are often only revealed during the early phases of domestication. When nearly insurmountable barriers were reached in some species, they have been (at least temporarily) eliminated from the pipeline. Conversely, a few species have moved quickly through the pipeline as hurdles, such as low seed weight or low seed number per head, were rapidly overcome, leading to increased confidence, farmer collaboration, and program expansion. Fil: DeHaan, Lee R.. The Land Institute; Estados Unidos Fil: Van Tassel, David L.. The Land Institute; Estados Unidos Fil: Anderson, James A.. University of Minnesota; Estados Unidos Fil: Asselin, Sean R.. University of Manitoba; Canadá Fil: Barnes, Richard. University of Minnesota; Estados Unidos Fil: Baute, Gregory J.. University of British Columbia; Canadá Fil: Cattani, Douglas J.. University of Manitoba; Canadá Fil: Culman, Steve W.. Ohio State University; Estados Unidos Fil: Dorn, Kevin M.. University of Minnesota; Estados Unidos Fil: Hulke, Brent S.. United States Department of Agriculture. Agriculture Research Service; Estados Unidos Fil: Kantar, Michael. University of British Columbia; Canadá Fil: Larson, Steve. Forage and Range Research Laboratory; Estados Unidos Fil: David Marks, M.. University of Minnesota; Estados Unidos Fil: Miller, Allison J.. Saint Louis University; Estados Unidos Fil: Poland, Jesse. Kansas State University; Estados Unidos Fil: Ravetta, Damián Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; Argentina Fil: Rude, Emily. University of Wisconsin; Estados Unidos Fil: Ryan, Matthew R.. Cornell University; Estados Unidos Fil: Wyse, Don. University of Minnesota; Estados Unidos Fil: Zhang, Xiaofei. University of Minnesota; Estados Unidos

Historically, agroecosystems have been designed to produce food. Modern societies now demand more from food systems—not only food, fuel, and fiber, but also a variety of ecosystem services. And although today's farming practices are producing unprecedented yields, they are also contributing to ecosystem problems such as soil erosion, greenhouse gas emissions, and water pollution. This review highlights the potential benefits of perennial grains and oilseeds and discusses recent progress in their development. Because of perennials' extended growing season and deep root systems, they may require less fertilizer, help prevent runoff, and be more drought tolerant than annuals. Their production is expected to reduce tillage, which could positively affect biodiversity. End-use possibilities involve food, feed, fuel, and nonfood bioproducts. Fostering multidisciplinary collaborations will be essential for the successful integration of perennials into commercial cropping and food-processing systems.

The pages of this extensive book document the potential of a great many North American plants to enhance the productivity, sustainability, and nutritional quality of crops or to be further developed into important cultivated species in their own right. But this potential can only be realized if the plants are adequately conserved to ensure their survival and availability for research, invested in to promote their development, and marketed so as to be attractive to producers and consumers. We outline some of the key steps needed to boost the conservation and use of our regional cornucopia. In situ and ex situ conservation of North America’s useful plants are being accomplished by a variety of institutions with different mandates, but habitat destruction and other threats to wild populations continue to negatively impact many species. Information sharing, coordinating efforts, filling research gaps for wild plants, and increasing support for conservation will be necessary to more comprehensively safeguard these plants and to make them available for use. Technologies enabling more efficient exploration of the diversity within these species are rapidly advancing and offer the potential to contribute to quick advances in improvement of cultivars, but considerable further research and partnerships are needed to generate and share the results widely. Marketing of new crops can take advantage of the increasing public interest in diverse and nutritious foods, learning from successful collaborations between producers, researchers, and consumers. As a whole, North America already possesses a strong foundation from which the conservation and use of its flora can be enhanced. This includes many protected areas, strong conservation institutions, innovative research, and the willingness to collaborate across fields, institutions, and borders. There are still many silos that need to be broken down and reorganized through innovative partnerships to better conserve and benefit from the North American cornucopia. But given the incredible diversity of interesting and useful plants in the region, the remarkable efforts for many decades by many organizations to care for these plants and share them with humanity, and the increasing public interest in more diverse, healthy, and resilient food and agricultural systems, there is reason for hope.

Changes in crop yield and production over time are driven by a combination of genetics, agronomics, and climate. Disentangling the role of these various influences helps us understand the capacity of agriculture to adapt to change. Here we explore the impact of climate variability on rice yield and production in the Philippines from 1987-2016 in both irrigated and rainfed production systems at various scales. Over this period, rice production is affected by variations in soil moisture, which are largely driven by the El Nino-Southern Oscillation (ENSO). We found that the climate impacts on rice production are strongly seasonally modulated and differ considerably by region. As expected, rainfed upland rice production systems are more sensitive to soil moisture variability than irrigated paddy rice. About 10% of the variance in rice production anomalies on the national level co-varies with soil moisture changes, which in turn are strongly negatively correlated with an index capturing ENSO variability. Our results show that while temperature variability is of limited importance in the Philippines today, future climate projections suggest that by the end of the century, temperatures might regularly exceed known limits to rice production if warming continues unabated. Therefore, skillful seasonal prediction will likely become increasingly crucial to provide the necessary information to guide agriculture management to mitigate the compounding impacts of soil moisture variability and temperature stress. Detailed case studies like this complement global yield studies and provide important local perspectives that can help in food policy decisions.

Climate change is expected to severely impact farming in sub-Saharan Africa. Now research shows that crop wild relatives might be able to secure Africa’s existing cropping practices by providing the genetic diversity needed to adapt crops to climates that they have never seen before.

Over the last half-century, crop breeding and agro- nomic advances have dramatically enhanced yields in temperate summer-annual cropping systems. Now, diversification of these cropping systems is emerging as a strategy for sustainable intensifica - tion, potentially increasing both crop production and resource conservation. In temperate zones, diversification is largely based on the introduc - tion of winter-annual and perennial crops at spatial and temporal locations in annual-crop production systems that efficiently increase production and resource conservation. Germplasm development will be critical to this strategy, but we contend that to be feasible and efficient, germplasm improve - ment must be closely integrated with commercial- ization of these crops. To accomplish this integra- tion, we propose a novel approach to germplasm development: the reflective plant breeding para - digm (RPBP). Our approach is enabled by develop- ments in genomics, agroecosystem management, and innovation theory and practice. These develop- ments and new plant-breeding technologies (e.g., low-cost sequencing, phenotyping, and spatial modeling of agroecosystems) now enable germ- plasm development to proceed on a time scale that enables close coordination of breeding and com- mercialization (i.e, development of cost-effective production systems and supply-value chains for end-use markets). The RPBP approach is based on close coordination of germplasm development with enterprise development. In addition to supporting strategic diversification of current annual-cropping systems, the RPBP may be useful in rapid adap- tation of agriculture to climate change. Finally, the RPBP may offer a novel and distinctive pathway for future development of the public plant-breeding programs of land-grant universities with implica- tions for graduate education for public- and private- sector plant breeders.

Indigenous crops, tremendously valuable both for food security and cultural survival, are experiencing a resurgence in Hawaiʻi. These crops have been historically valued by agricultural researchers as genetic resources for breeding, while cultural knowledge, names, stories and practices persisted outside of formal educational and governmental institutions. In recent years, and following conflicts ignited over university research on and patenting of kalo (Hāloa, Colocasia esculenta), a wave of restoration activities around indigenous crop diversity, cultivation, and use has occurred through largely grassroots efforts. We situate four crops in Hawaiian cosmologies, review and compare the loss and recovery of names and cultivars, and describe present efforts to restore traditional crop biodiversity focusing on kalo, ʻuala (Ipomoea batatas), kō (Saccharum officinarum), and ʻawa (Piper methysticum). The cases together and particularly the challenges of kalo and ‘awa suggest that explicitly recognizing the sacred role such plants hold in indigenous worldviews, centering the crops’ biocultural significance, provides a foundation for better collaboration across multiple communities and institutions who work with these species. Furthermore, a research agenda that pursues a decolonizing approach and draws from more participatory methods can provide a path forward towards mutually beneficial exchange among research, indigenous, and farmer communities. We outline individual and institutional responsibilities relevant to work with indigenous crops and communities and offer this as a step towards reconciliation, understanding, and reciprocity that can ultimately work to create abundance through the restoration of ancestral crop cultivar diversity.

Perennial agriculture has been proposed as an option to improve the sustainability of cropping systems, by increasing the efficiency of resource use, while also providing ecosystem services. Neo-domestication, the contemporary domestication of plants that have not previously been used in agriculture, can be used to generate new crops for these systems. Here we explore the potential of a tetraploid (2n = 4x = 68) interspecific hybrid sunflower as a perennial oilseed for use in multifunctional agricultural systems. A population of this novel tetraploid was obtained from crosses between the annual diploid oilseed crop Helianthus annuus (2n = 2x = 34) and the perennial hexaploid tuber crop Helianthus tuberosus (2n = 6x = 102). We selected for classic domestication syndrome traits for three generations. Substantial phenotypic gains were made, in some cases approaching 320%. We also analyzed the genetic basis of tuber production (i.e., perenniality), with the goal of obtaining molecular markers that could be used to facilitate future breeding in this system. Results from quantitative trait locus (QTL) mapping suggest that tuber production has an oligogenic genetic basis. Overall, this study indicates that substantial gains towards domestication goals can be achieved over contemporary time scales.

Natural populations across a species range demonstrate population structure owing to neutral processes such as localized origins of mutations and migration limitations. Selection also acts on a subset of loci, contributing to local adaptation. An understanding of the genetic basis of adaptation to local environmental conditions is a fundamental goal in basic biological research. When applied to crop wild relatives, this same research provides the opportunity to identify adaptive genetic variation that may be used to breed for crops better adapted to novel or changing environments. The present study explores an ex situ conservation collection, the USDA germplasm collection, genotyped at 32,416 SNPs to identify population structure and test for associations with bioclimatic and biophysical variables in Glycine soja, the wild progenitor of Glycine max (soybean). Candidate loci were detected that putatively contribute to adaptation to abiotic stresses. The identification of potentially adaptive variants in this ex situ collection may permit a more targeted use of germplasm collections.

The White Earth Tribe of Ojibwe and the University of Minnesota have partnered to identify antimicrobial properties in native plant species in the Upper Mississippi River and Red River Basins. Optimization of harvest time, tissue preparation, and extracting solvent methods was completed using extracts from two species with known antimicrobial activity, Betula papyriferaand Rhus typhina. Tissue was collected at three different times (July, August, and September) corresponding to different developmental states (juvenile, reproductive, post-reproductive) and extracts were prepared from fresh, frozen, or dried tissue using one of three solvents, acetone, ethanol, or methanol. Using optimized methods plant extracts from 265 above ground plant components (flower, leaves, stems, berries) of 130 species were tested against four microorganisms (Escherichia coli, Pseudomonas aeruginosa, Candida albicans,Staphylococcus aureus). Eighty extracts were found to inhibit at least one microorganism. Sixteen extracts inhibited two microorganisms, six extracts inhibited three microorganisms, and three extracts inhibited all four microorganisms. Extracts from R. typhina and B. papyrifera leaves were also tested against soil borne pathogens, Fusarium solani, Phytophthora sojae, Rhizoctonia solani, and Pythium spp, in order to assess potential uses as seed protectants. Rhus spp extracts inhibited F. solani and Pythium spp as well as a commercial fungicide seed treatment applied as a control. Key words: Antimicrobial, native plants, antifungal seed treatment.