Both natural and man-made disasters often drastically affect food and nutrition security. For instance, the Ethiopian famines of the 1970s' and 1980s' proved lethal for many, especially before foreign aid (Crummey, 2018). More recently, droughts in Australia and the COVID-19 pandemic have highlighted the fragility of many food supply chain networks (Singh-Peterson and Lawrence, 2015; Deconinck et al., 2021). These disasters and their effects on food security would pale in comparison to sun-blocking global catastrophic risks (GCRs), such as a nuclear war, asteroid strike, or super volcano eruption. For example, several crop models have clearly predicted that any-scale nuclear war between nations would significantly decrease food production across the globe (Denkenberger and Pearce, 2015; Xia et al., 2015; Jagermeyr et al., 2020). In addition to inevitable supply-chain disruptions after a GCR, severe climate-shifts to a drier, colder, and darker environment would drive crop production decline for many years (Toon et al., 1979, 2019; Coupe et al., 2019). The annual risk of a nuclear war occurring has been estimated as high as 1%, which could certainly continue to be decreased with more strategic diplomacy (Barrett et al., 2013). Concurrently, the world has seen unprecedented and rapid shifts in climate warming, causing more frequent and more severe natural disasters (Garner et al., 2017; Smith et al., 2022). Both the increased risk of natural disasters and higher risk of GCRs mean that creating a more resilient global food system is even more important than ever.

One strategy for food sustainability and resilience, even through disasters, is by increasing and preserving agrobiodiversity. Agrobiodiversity is very broadly defined by the FAO as “the variety and variability of animals, plants and micro-organisms that are used directly or indirectly for food and agriculture, including crops, livestock, forestry, and fisheries. It comprises the diversity of genetic resources (varieties, breeds) and species used for food, fodder, fiber, fuel, and pharmaceuticals. It also includes the diversity of non-harvested species that support production (soil micro-organisms, predators, pollinators), and those in the wider environment that support agro-ecosystems (agricultural, pastoral, forest, and aquatic) as well as the diversity of the agro-ecosystems” (FAO, 1999). Increases in agrobiodiversity mean increased resilience to any changes in the environment and can help dampen the effects from climate change on food production, such as drought (Gonzalez, 2011; Ortiz, 2011; Chivenge et al., 2015). In addition to resiliency from climate change, agrobiodiversity also protects against the spread of crop diseases and buffers yield losses (Gonzalez, 2011). In addition to direct crop-system resilience, increased agrobiodiversity leads to better overall nutrition, boosts in local economies, community independence, and cultural preservation (Birol et al., 2006; Gonzalez, 2011; Dwivedi et al., 2013; Bioversity International., 2019; Mabhaudhi et al., 2019; Odhiambo et al., 2019; Chatzopoulou et al., 2020; Carney, 2021; Tamariz, 2022). If done correctly, agrobiodiversity can also increase native biodiversity by emulating native environments (Gonzalez, 2011; Khumalo et al., 2012).

According to Bioversity International. (2020), the United States scores below average on their agrobiodiversity index compared to other developed nations. Likewise, the US government does not seem to be prioritizing plans for increasing or preserving agrobiodiversity resources for the future, exemplified by their not submitting a National Biodiversity Strategies and Action Plan (NBSAP) to the Convention on Biological Diversity (Jones et al., 2021). To increase the resilience of the US agricultural and food system to these many potential future threats, actions need to be taken to prioritize strategies of increasing and preserving agrobiodiversity resources within US agroecosystems, preferably at a local scale (Paci-Green and Berardi, 2015; Bioversity International., 2019).

North America has no shortage of available plants to use for this purpose, having thousands of seldom-used wild edible plants (WEP)s and hundreds of unique crop varieties (Moerman, 1998; Veteto, 2014). The crops and WEPs once used abundantly by Native Americans are a largely underutilized resource of North America and if developed and valorized could increase the United States' agrobiodiversity, and consequently, food resilience in the face of disaster events and a changing climate (Small, 2013; Bioversity International., 2019). Sadly, much of the knowledge on how to use these species was lost with the extermination and extirpation of many Native American people groups (Moerman, 1998; Veteto, 2014). Even those plant species that were not necessarily domesticated by Native Americans may have still been grown in manipulated ecosystems for the purpose of increased yield and not natural “wild” landscapes (Hladik et al., 1993). For these reasons, we have refrained from using the term WEPs, as the line between wild and semi-domesticated plants is somewhat blurred and cannot be confirmed because some of those who used these plants are no longer living. Throughout this paper we will refer to these plants once used as staple foods by Native American as Native American food plants (NAFPs).

The purpose of this study is to better direct the attention of researchers and industry leaders toward NAFPs that would increase nutritional, economic, and ecological resilience of the United States. The NAFPs with the most available research are likely the most useful options as an abundant foundation of knowledge and focused attention is needed for the efficient use and scaling up and profitability of any new crop and plant resource (Cerón-Souza et al., 2021). In this study we propose a list of several plant species and genetic resources of interest, that would increase America's agrobiodiversity and food resilience if preserved and valorized.

To create this list of species and cultivars, we have conducted a literature review on species listed as “staple foods” in Daniel Moerman's book and database Native American Ethnobotany (Moerman, 1998), which was created using primary records and ethnographic studies of 291 native people groups in North America. The top NAFPs in this literature review will be highlighted with their nutritional content and possible yields if available in the literature.

A total of 225 NAFPs are listed in Daniel Moerman's book as being used as “Staple” foods by one or more native nations of North America. Of those plants, 196 are native to North America. Of those, 7 do not have species level identification listed and 11 are duplicated as different subspecies. Of the remaining 178 plants, 4 were excluded from the literature search as they have become common mainstream domesticated crops. Those species were cayenne pepper (Capsicum annuum), field pumpkin (Cucurbita pepo), wild strawberry (Fragaria vesca), and common sunflower (Helianthus annuus). The remaining 174 plants were used in the systematic literature review.

The systematic literature review was conducted with the following criteria using Penn States available 940 databases accessed between 03/23/2022 - 11/20/2022: Literature published between 03/23/1982 – 03/23/2022, only Peer-Reviewed articles, only articles in English, only search titles of articles (Figure 1). The purpose of limiting the keyword search to only within the title is to only focus on research that is prioritizing or valorizing specific NAFPs and not merely mentioning them. The genus and species of each NAFP (i.e., “Genus species”) was then searched using the criteria and all available literature was then categorized into one or more subjects with the definitions in Table 1. All duplicates or articles in other languages other than English were not included in total numbers. In addition to the literature review, the regionality, botanical family, habit, ecological status (Either IUCN or NatureServe if IUCN not available), part(s) used, and duration (annual, perennial, or biannual) for each NAFP were collected. Plant region data were gathered from the USDA Plant Database and regionality assigned to plants depending on the states and provinces they were native to Supplementary material.

The micro- and macronutrient profiles of these plants were compiled using available literature and their nutritional density scores, and powerhouse fruit and vegetable (PFV) scores were calculated if enough nutrient value information was available using the methods from di Noia (2014). These scores were calculated using the following equations, where “nutrient_i” is one of 17 nutrients chosen by di Noia (2014) for evaluation:

The top ten NAFPs with the most total peer-reviewed literature available, top ten NAFPs with the most nutritional articles, and top ten annual NAFPs with the most total peer-reviewed literature available were compiled into a list (excluding duplicates) (Table 2). Among the top 24 selected plants, only Zizania spp. and Amaranthus spp. had all data available to calculate a nutrient adequacy score, therefore if more than half of the nutrient data was available, a nutrient adequacy score was calculated.

A total of 5,302 peer-reviewed articles were categorized and codified for 127 of the staple NAFPs. Yet, 47 of the reviewed NAFPs from Moerman's database did not have any peer-reviewed literature available with their species name in the title over the past 40 years among the databases available to Penn State University Libraries. Only 32 NAFPs had any nutritional literature available about them in the last 40 years.

Although there was more information available on some of these NAFPs' nutrition, only data on the raw whole portion of plant used as a staple food was considered when evaluating the 24 NAFPs' micro- and macronutrients (Table 3) (Darmon et al., 2005; di Noia, 2014). Even still some plants only had genus specific nutritional data which we have labeled accordingly. These nutritional values and nutrition adequacy scores for species are compared with yellow corn grain in Table 4. Among the NAFPs examined, the genus Zizania had the highest nutrient adequacy (22.69) and nutrient density score (6.36), followed by the genus Amaranthus (16.38 and 4.4, respectively). These values were higher than the yellow corn nutrient adequacy score (13.61) and nutrient density score (3.73). All the other NAFPs considered had nutrient adequacy and density scores similar to or lower than yellow corn grain, with Vaccinium myrtillus having the lowest nutrient adequacy score.

Currently, the most researched NAFPs for their nutrition and domestication are Mojave Yucca (Yucca schidigera), Whortleberry (Vaccinium myrtillus), Saskatoon serviceberry (Amelanchier alnifolia), and tepary bean (Phaseolus acutifolius). However, most literature for Mojave yucca was directed toward its use as a feedstock for animals rather than the nutritional value of its fruits, which is the plant part listed as a staple for Native American nations. The NAFPs with the most available nutritional values were amaranth (Amaranthus spp.), black walnut (Juglans nigra), wild rice (Zizania spp.), Saskatoon serviceberry (Amelanchier alnifolia), and acorns (Quercus spp.). Although these top five have the most nutritional information available, three of them are only to genus level, and most values for black walnut are for the dried nut and not raw. This leaves Saskatoon serviceberry with the most available nutritional values and one of the plants with the most literature available making it a good candidate for domestication and use.

Most plants reviewed could be found in the Western US (88.5% of NAFPs), or Southwest US (70.7% of NAFPs). The least represented areas were the central, Atlantic, and northern Canadian regions. Only 14.9% of staple NAFPs had ecological statuses that were not a G5 NatureServe rating or Least Concern IUCN rating. There were 45 botanical families represented among the listed staple NAFPs. The five most commonly represented botanical families among the staple NAFPs were the oak and beech family (Fagaceae: 19), sunflower and daisy family (Asteraceae: 16), grass family (Poaceae: 15), cactus family (Cactaceae: 14), and bean family (Fabaceae: 11).

Our systematic review exposes the lack of literature and ongoing development of NAFPs and their domestication. The lack of substantial nutritional research for most of the listed staple NAFPs shows the lack of interest, funding, and attention to these food crops and likewise, the lack of attention to Native American voices and cultures. Similarly, more literature on NAFPs had been focused on decreasing their growth and prevalence as weeds rather than on how to increase their growth and prevalence through horticultural methods. More than half of the available literature on these staple NAFPs fell under the ecological or organismal study categories, with the next most interest being their pharmaceutical value.

Only 18.4% of staple NAFPs have any literature concerning their nutritional value, and only eight NAFPs have more than five articles on their nutritional value. This shows the overall lack of attention on this group of plants as an agricultural resource. The staple NAFPs regionality follow similar geographic trends to plant diversity geographical distribution in North America, where there is more diversity the farther south in latitude and west in longitude on the North American continent (Qian, 1999).

Wild rice, amaranth seeds, and saskatoon serviceberry all have nutrient adequacy scores and nutrient density scores higher than yellow corn grain. Although there is not much species-specific nutritional information for the species listed in this review, it is important to note that many are congeners with other food plants. It has been shown that plants of the same genus usually have similar nutritional profiles, meaning that many of the plants listed, although understudied, have high nutritional potential given their relation to other nutritious plants (Cantwell-Jones et al., 2022).

Love and Spaner (2007) suggest that “conservation of agrobiodiversity is a prerequisite for the development of sustainable agricultural systems.” The state of research of NAFPs in North America leaves much to be desired. Although there is current research on some of these staple NAFPs, most of this research has no focus on their nutritional value or potential domestication. We have discussed how the incorporation of these staple NAFPs into the U.S. agricultural system, would increase the resilience of the U.S. food system. The partnership and approval of Native American nations toward domestication pipelines for staple NAFPs with clear delineations on GMO statuses is imperative. As the risk and likelihood of catastrophes and one-off disaster occurrences increase, so also should the U.S. agricultural system grow in its resilience to anticipate these increased risks. We have shown that the limited literature available for the nutritional information of NAFPs is promising by their high Powerhouse Fruit and Vegetable value scores. Future research should focus on the incorporation of these NAFPs into government incentive programs and school food systems, as well as the domestication of the most well-known and highly nutritious NAFPs. Although the U.S. agricultural system is currently mostly monoculture agronomy systems, proper government incentive programs and accessibility to post-harvest preparation would facilitate NAFP agroforestry as there is already farmer interest. Not only do these changes have direct agricultural benefits, but the valorization of NAFPs may lead to a valorization of the voice and culture of many Native American nations and the conservation of our native biodiversity.

The original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author.

DW and FD developed the idea. DW, FD, and MJ contributed to conception and design of the work. DW conducted the literature search, organized the database, conducted the analysis, and with the support of FD and MJ wrote the first draft of the manuscript. All authors contributed to manuscript revision, read, and approved the submitted version.