Apios americana

Apios americana, sometimes called theAmerican groundnut,potato bean,hopniss,Indian potato,hodoimo,America-hodoimo,cinnamon vine, orgroundnut(not to be confused with other plants in the subfamilyFaboideaesometimes known by that name) is aperennialvinethat bears ediblebeansand large edibletubers.
The vine of American groundnut can grow to1–6 metres (3+1⁄2–19+1⁄2feet) long. It has pinnateleaves8–15 centimetres (3–6 inches) long with 5–7 leaflets.The flowers are usually pink, purple, or red-brown, and are produced in denseracemes7.5–13 cm (3–5 in) in length.The fruit is alegume(pod) 5–13 cm (2–5 in) long.In botanical terms, thetubersarerhizomatousstems, not roots.
The species is normally 2n=2x=22,diploid, but both diploid andtriploidforms exist.Only diploids are capable of producing seeds; triploids will produce flowers but not seeds.Thus, triploids are entirely dependent on tuber division for propagation whereas diploids can be propagated through both seeds and tubers.Other than seed production, there are no easily identifiable differences between diploids and triploids.Triploids are generally found in the northern part of American groundnut's range whereas diploids predominate in the southern part of the range.Triploids have been identified in Canada (inNew Brunswick,Quebec, andOntario) and the United States (inConnecticut,Vermont,Massachusetts,New York,Pennsylvania,Ohio,New Hampshire,Rhode Island,Wisconsin, andIowa).A few diploids have been found in the northeastern part of the range, such as along theBlack RiverinCentral Ontario.All samples tested in theSoutheastern United Stateshave been found to be diploid.
The plant's natural range is from southern Canada (including Ontario, Quebec, and New Brunswick) down throughFloridaand west as far as the border ofColorado.
The species is a larval host for theEpargyreus clarus.
American groundnutfixesits ownnitrogen, which could be a great advantage in comparison to other roots crops, such as potatoes,true yams, and sweet potatoes. These do not fix their own nitrogen and require large applications of nitrogen fertilizer or cover cropping with nitrogen fixing plants.American groundnut can be nodulated by bacterial strains that are normally found in symbiosis with soybeans or cowpeas.
Research has been done on the potential of the soybean strainBradyrhizobium japonicumto nodulate American groundnut.It was found that plants nodulated withB. japonicumyielded ~30% better than unnodulated plants if no nitrogen fertilizer was used.It was also determined that nodulated plants partitioned more carbon into non-edible shoots when they were given nitrogen fertilizer, whereas unnodulated plants responded to nitrogen fertilizer with greater tuber yields than nodulated plants.This data suggests that nitrogen fertilization may be required to maximize tuber size and yields inA. americana.
The American groundnut is generally considered to be an undomesticated crop. In her 1939 description of the Native American use of American groundnut, Gretchen Beardsley states that several historical sources describe the "cultivation" of American groundnut by indigenous peoples. She dismisses the ambiguous term "cultivation" as perhaps referring to the transplantation of tubers near a settlement. She quotes the historical author Waugh on this subject of cultivation: "sometimes planted in suitable locations, though they are not, strictly speaking, cultivated."Subsequent authors on the American groundnut have followed Beardsley's interpretation of "cultivation" when referring to the early use by Indigenous peoples of American groundnut. However, recent evidence suggests that North American indigenous peoples likely intervened significantly as cultivators of the native plants of the region, in a manner similar to contemporary Westernpermaculturepractices.So, from a permacultural perspective, Native Americans may well have "cultivated" the groundnut. Evidence suggests it was cultivated by the Shawnee tribe with corn and squash in a method known as three sisters gardening. Apios would provide nitrogen for the heavy-feeding squash.
In 1985, Dr. William J. Blackmon, Dr. Berthal D. Reynolds, and their colleagues atLouisiana State UniversityinBaton Rouge,Louisiana, began a program of deliberate domestication of American groundnut. Their primary goal was to develop an American groundnut that can produce a significant yield in a single season.Early trials identified LA85-034 as a promisingcultivar, with "elongate tubers of uniform, medium size with light brown skin and little extra rhizomatous material".By 1988, they had collected wild seeds and tubers from 210 plants found in 19 states, although the bulk of their selections came from the state of Louisiana.From these wild materials, and a small number of single crosses, they rigorously selected for plants that met their primary breeding goals of larger tuber size, denser tuber set, single season production, and productivity in untrellised cultivation.The American groundnut domestication program at Louisiana State University continued in various forms until the mid-1990s.Cultivars from this program can still occasionally be found available from small seed companies.
From 1985 to 1994, anApiosbreeding program took place that resulted in the collection of over 200 wild accessions. These accessions underwenthybridizationand selection, and over 2,200 lines were assessed.Of these lines, only 53 genotypes were kept for further analysis. Three different locations and three different growing conditions—field, pots, and grow-bags—were used. There was significant variation found among almost all of the 20 genotypes in the field growing condition. Inter-node length, plant vigor, and stem diameter during plant growth were positively correlated with the plant yield below ground.There were four distinct genotypic clusters found in this collection ofApioslines. Several genotypes yielded large plants in all locations, maxing up to 1.5 kilograms (3.3 pounds) of subterraneous tuber.This suggests that the plant has a good ability to adapt and grow in a wide variety of locations and conditions. Furthermore, the superior germplasm identified in this project may be suitable as cultivars, and will aid in further development ofApioslines as a crop.
The largest germplasm collection ofA. americanacultivars today is found atIowa State Universityunder the direction of Dr. Steven Cannon.It is maintained there for scholarly and academic use. Research continues at Iowa State on the domestication of American groundnut.
Despite these efforts at domestication, the American groundnut remains largely uncultivated and underused in North America and Europe.There are challenges to breeding and domesticating this plant, as well.There seems to be a partial self-incompatibility withApiosbreeding and manual pollinations, resulting in rare seed-sets.Disadvantages inApiosas a crop are its vining habit.The crop has small tuber size for most genotypes.These sizes are typically smaller than 50 g (1.8 oz); however, some do average around 100 g (3.5 oz).The tuber plant is difficult to harvest because of the "beads on a string" arrangement onstolons, which extend for over a meter.
The only place in the world today where American groundnuts are commercially farmed in any significant quantities is inJapan.Before the American groundnut was introduced to Japan, the people on the main island ofHonshuand the northern island ofHokkaidowere already familiar with a native, wild plant called hodoimo (A. fortunei), which was occasionally eaten as an emergency food.American groundnut was introduced, accidentally or deliberately, to Japan during theMeiji period(1868–1912).One theory is that it was accidentally brought to Japan as a stowaway weed amongappleseedlings imported from North America.Another theory is that American groundnut may have been deliberately brought to Japan in the middle of the Meiji period as an ornamental flower.
It has become a culinary specialty of theAomori Prefecture, where American groundnut agriculture is centered. It has been eaten there for more than one hundred years.Although American groundnut agriculture is primarily identified with agriculture in the Aomori prefecture, it is grown in the nearby prefectures of Akita and Miyagi as well.In addition, it is known to be grown in the southern part of Honshu in the Tottori prefecture. Radioactive testing records following theFukushima nuclear disasterrecord cesium testing of American groundnut agricultural products in the central prefecture of Tochigi.
An important part of the spread and popularization of American groundnut consumption in Japan has been the efforts of Dr. Kiyochika Hoshikawa to promote the cultivation of this crop in Japan, and the flurry of scientific articles on the health benefits of eating American groundnut tubers.Japanese websites that sell American groundnut continue to emphasize its health benefits in their marketing efforts.There are reports of American groundnut cultivation inSouth Koreaas well, where it is grown for its nutritional benefits.
Studies in rats suggest that raw tubers should not be consumed. They contain harmfulprotease inhibitorsthat are denatured by cooking.
The tubers and seeds can both be cooked and eaten.
The tubers have traditionally been astaple foodamong mostIndigenous peoples of the Americaswithin the natural range of the plant.In 1749, the travelling Swedish botanist Peter Kalm writes, "Hopniss or Hapniss was the Indian name of a wild plant, which they ate at that time... The roots resemble potatoes, and were boiled by the Indians who ate them instead of bread."Strachey in 1612 recorded observations of the Indigenous peoples inVirginia: "In June, July, and August they feed upon roots oftockohow, berries, groundnutts, fish, and greene wheate..."In EasternCanada, the Jesuit missionary, Le Jeune, observed  that the Indigenous peoples there would, "eat, besides, roots, such as the bulbs of the red lily; ... another that our French people call 'Rosary' because it is distinguished by tubers in the form of beads."The early author Rafinesque observed that theCreewere cultivating the plant for both its tubers and seeds.The author Brinton wrote in 1885 in regards to theLenapepeople, "Of wild fruits and plants they consumed the esculent and nutritious tubers on the roots of the Wild Bean, Apios tuberosa... which the Indians called hobbenis..."In 1910, Parker writes that theIroquoiswere consuming significant quantities of groundnuts up until about thirty years before his writing.The Paris Documents of 1666 record that the sixth tribe of the second division of the Iroquois were identified as, "that of the Potatoe, which they call Schoneschironon" and an illustration of tubers is found in the Paris Documents with the explanation, "This is the manner they paint the tribe of the Potatoe."The author Gilmore records the use of groundnuts by theCaddoanand Siouan tribes of the Missouri river region, and the authors Prescott and Palmer record its use among theSioux.The Indigenous peoples would prepare the tubers in many different ways, such as frying them in animal fat or drying them into flour.Many tribes peel them and dry them in the sun, such as theMenominiwho have traditionally built scaffolds of cedar bark covered with mats to dry their tubers for winter use.The Menomini are recorded as having dried the tubers inmaple syrupor making a preserve of Groundnut tubers by boiling them in maple syrup.ThePotawatomihave traditionally boiled their tubers.The traditionalMeskwakiandChippewapreparation involves peeling, parboiling, slicing, and drying the tubers. The Chippewa have historically used them as a sort of seasoning in all their foods.
The Europeans learned to use the American groundnut from the Indigenous peoples of the Americas. As a result, the American groundnut became interwoven with the history of the American colonies andEurope. The early travelerJohn Breretonwas sustained by the "good meat" and "medicinable" qualities of American groundnut during his travels inNew Englandin 1602.In 1613, the followers of Biencourt atPort-Royalate the tubers to help them survive in the New World.The American groundnut was an important factor in the survival of the Pilgrims during the first few winters of their settlement.In 1623 the Pilgrims, "having but a small quantity of corn left," were "enforced to live on groundnuts... and such other things that the country afforded... and were easily gotten..."The Pilgrims were taught to find and prepare American groundnut by theWampanoag people.The groundnut was likely eaten at the harvest festival of November 1621 that is regarded as the firstThanksgiving, although onlyvenisonwas specifically named as a food item at this meal by a Pilgrim eyewitness account.
PhilosopherHenry David Thoreaucommented on the nutty flavor and dry texture in October 1852.
It is believed that American groundnut may have been shipped to Europe as early as 1597. It was listed in 1885 as a European garden crop.In 1845 it was evaluated as a possible alternative potato crop in Ireland during theGreat Famine.These early introductions to Europe appear to have resulted in little or no assimilation of the new food into the European diet.A primary reason for this lack of assimilation was that the two-year cycle for an acceptable tuber yield did not match the cropping systems that were familiar to Europeans.
The tubers are highly palatable with culinary characteristics of a potato, although the flavor can be somewhat nuttier than a potato and the texture can be finer.These tubers contain roughly three times the protein content of a potato (16.5% by dry weight), and theamino acidbalance is good with the exception ofcysteineandmethionine.A. americanatubers were found to have a protein concentration of 15–30 milligrams per gram (0.24–0.48 ounces per pound),similar to that of other species in the genus,A. carneaandA. fortunei.However,A. americanahad larger levels ofgenisteinthan the other two species.Thefatty acidcontent of tubers is approximately 4.2% to 4.6%, with linoleic fatty acids predominating.The fresh weight of a tuber is 36% ofcarbohydrate(primarily starch).The tubers are also an excellent source of calcium and iron.Calciumcontent is tenfold greater than a potato andironis twofold greater than a potato, althoughvitamin Cwas considerably less than a potato.The tuber and the flower also containmonosaccharidesandoligosaccharides.The tuber has more of these types of carbohydrates than thesoybean, potato, andsweet potato.
In addition, the tubers appear to have numerous health-promoting factors. Hypertensive rats that were fed powdered tubers as 5% of their total diet had a 10% decrease in blood pressure and also a reduction incholesterolandtriglycerides.It has been shown that the tubers contain genistein and otherisoflavonesthat have various health benefits, including an anti-carcinogenic function against colon, prostate, and breast cancer.Genistein-7-O-gentiobioside is a novel isoflavone that is found in the American groundnut.Extract from the American groundnut was shown to drive the anti-oxidative pathway in cells although it did not have anti-oxidative activity itself.Human breast carcinoma MCF-7 cells were pretreated with the extract ofA. americanafor 24 hours.Subsequent analysis showed an increase in expression ofheme oxygenase-1, a protein induced during oxidative stress.The American groundnut, like soybean, is a great source ofisoflavone.
Furthermore, a study onA. americanaand its flower shows that the flower of the particular plant is not toxic to mice.Consumption of the flower was shown to lower plasma glucose levels in diabetic mice.The flower was shown to have an inhibitory activity onmaltoseand an anti-hyperglycemic effect in mice, suggesting that not only is it a viable and novel food source for the general population, but also in the prevention ofdiabetes.