Perennial vegetables: A neglected resource for biodiversity, carbon sequestration, and nutrition

meet nutrient needs and b) an emphasis is placed on woody PVs rather than vines and herba- ceous perennials. PVs offer a modest but important contribution to agricultural climate change mitigation on vegetable cropland. Potential global impact of improved management of all global cropland is estimated at 1,400–2,300 MMT CO2-eq by 2050 [14]. As 3.5% of world cropland is in vegetable production currently [6], the mitigation potential for this land is 49–80 MMT CO2-eq/yr in 2050 under improved management. Increased PV adoption would sequester 22.7–280.6 MMT CO2-eq in 2050, demonstrating a notable improvement in carbon dioxide removal and storage in soils and perennial biomass via the partial perennialization of vegetable production. Perennial crops, as a class, are not more nutritious than annual crops as a class. Indeed some annual crops (notably the Amaranthus species) greatly exceed the nutrition of the refer- ence crops, clearly standing out for their ability to address nutrient deficiencies. However, the nutrition of perennials as a class, and of many individual perennial crops, certainly outper- forms the reference vegetables tracked by FAO (the reference vegetables include both annuals and perennials, but only those that are widely grown and traded). The high frequency of super- abundance in woody PVs is clearly shown in Fig 4. Table 5. Multi-nutrient species to address industrial diet deficiencies. Name Form Thermal Climate Moisture Part Fiber Ca Mg A C E Asclepias syriaca Perennial herb Temperate Humid, semi-arid Leaf VH VH XH

Atriplex halimus Woody Tropical, temperate Humid semi-arid, arid Leaf VH XH XH Bambusa polymorpha Woody Tropical Humid Shoot VH VH VH Cnidoscolus aconitifolius Woody Tropical Humid semi-arid, arid Leaf VH VH XH VH Coccinia grandis Perennial vine Tropical Humid Leaf, unripe fruit VH H XH Dicliptera chinensis Perennial herb Tropical Humid Leaf VH VH XH Epilobium angustifolium Perennial herb Temperate, boreal/arctic Humid, semi-arid Shoot H H VH VH Gnetum gnemon Woody Tropical Humid Leaf VH H H VH H Limnocharis flava Perennial herb Tropical Aquatic Leaf, stem, flowerbud VH XH XH H Manihot esculenta Woody Tropical Humid, semi-arid Leaf H VH VH XH XH Momordica cochinchinensis Perennial vine Tropical Humid Leaf, unripe fruit, fruit H VH VH XH XH Moringa oleifera Woody Tropical Humid, semi-arid Leaf, unripe fruit, flowerbud H VH VH VH VH H Morus alba Woody Tropical, temperate Humid, semi-arid Leaf VH VH VH VH VH Pisonia umbellifera Woody Tropical Humid Leaf VH VH VH Sauropus androgynus Woody Tropical Humid Leaf VH VH XH Senna obtusifolia Woody Tropical Humid Leaf� VH XH VH Senna sophera Woody Tropical Humid Leaf H VH VH VH Sesbania grandiflora Woody Tropical Humid Leaf XH VH VH H H Silene vulgaris Perennial herb Temperate, boreal/arctic Humid, semi-arid Leaf VH VH XH Solanum aethiopicum Perennial herb Tropical� Humid, semi-arid Leaf VH VH XH Toona sinensis Woody Tropical, temperate Humid, semi-arid Leaf VH XH VH XH

Trichanthera gigantea Woody Tropical Humid Leaf XH XH Urtica dioica Perennial herb Temperate, boreal/arctic Humid Leaf H VH H VH XH Vitis vinifera Perennial vine Tropical, temperate Humid, semi-arid Leaf XH VH VH VH H “Tropical” indicates lowland tropics, highland tropics, and/or subtropics. “Temperate” indicates warm temperate and/or cold temperate. “Boreal/arctic” indicates boreal and/or arctic. �Perennial frequently grown as an annual. “XH” indicates extremely high levels, over twice the highest level found in the reference crops. “VH” indicates very high levels between the highest level of reference crops and double the level of reference crops. “H” indicates high levels, in the highest tertile of the reference crops. � Cultivated for its young leaves as a vegetable in four African countries, but mature leaves are a powerful laxative [36]. https://doi.org/10.1371/journal.pone.0234611.t005 PLOS ONE Perennial vegetables: A neglected resource for biodiversity, carbon sequestration, and nutrition PLOS ONE | https://doi.org/10.1371/journal.pone.0234611 July 10, 2020 13 / 19