Einkorn

Einkorn wheat (from German Einkorn, literally "single grain") can refer to either a wild species of wheat (Triticum) or a domesticated form of wheat. The wild form is T. boeoticum (syn. T. m. subsp. boeoticum), and the domesticated form is T. monococcum (syn. T. m. subsp. monococcum). Einkorn is a diploid species (2n = 14 chromosomes) of hulled wheat, with tough glumes (husks) that tightly enclose the grains. The cultivated form is similar to the wild, except that the ear stays intact when ripe<ref name = "Complex-Origins" /> and the seeds are larger. The domestic form is known as {{#invoke:Lang|lang}} in French, {{#invoke:Lang|lang}} in German, "einkorn" or "littlespelt" in English, {{#invoke:Lang|lang}} in Italian and {{#invoke:Lang|lang}} in Spanish.<ref name=LeBrun1992>Template:Cite journalTemplate:Open access</ref> The name refers to the fact that each spikelet contains only one grain.

Einkorn wheat was one of the first plants to be domesticated and cultivated. The earliest clear evidence of the domestication of einkorn dates from 10,600 to 9,900 years before present (8650 BCE to 7950 BCE) from Çayönü and Cafer Höyük, two Early Pre-Pottery Neolithic B archaeological sites in southern Turkey.<ref>Template:Cite journal</ref> Remnants of einkorn were found with the iceman mummy Ötzi, dated the late 4th millennium BCE.<ref>Template:Cite magazine</ref>

Description

Einkorn is a short variety of wild wheat, usually less than Template:Convert tall and is not very productive of edible seeds.<ref name=ZoharyHopf3343/> The principal difference between wild einkorn and cultivated einkorn is the method of seed dispersal. In the wild variety the seed head usually shatters and drops the kernels (seeds) of wheat onto the ground.<ref name="Complex-Origins"/> This facilitates a new crop of wheat. In the domestic variety, the seed head remains intact. While such a mutation may occasionally occur in the wild, it is not viable there in the long term: the intact seed head will only drop to the ground when the stalk rots, and the kernels will not scatter but form a tight clump which inhibits germination and makes the mutant seedlings susceptible to disease. But harvesting einkorn with intact seed heads was easier for early human harvesters, who could then manually break apart the seed heads and scatter any kernels not eaten. Over time and through selection, conscious or unconscious, the human preference for intact seed heads created the domestic variety, which has slightly larger kernels than wild einkorn. Domesticated einkorn thus requires human planting and harvesting for its continuing existence.<ref>Weiss and Zohary, pp. S239–S242</ref> This process of domestication may have taken only 20 to 200 years, resulting in a wheat that was easier to harvest.<ref>Template:Cite book</ref>

An important characteristic facilitating the domestication of einkorn and other annual grains is that the plants are largely self-pollinating. Thus, the desirable (for human management) traits of einkorn could be perpetuated at less risk of cross-fertilization with wild plants which might have traits – e.g. smaller seeds, shattering seed heads,<ref name = "Complex-Origins" >Template:Cite journal</ref> as less desirable for human management.<ref>Template:Cite book</ref>

Ecology and distribution

Einkorn wheat commonly grows wild in the hill country in the northern part of the Fertile Crescent and Anatolia, although it has a wider distribution reaching into the Balkans and south to Jordan near the Dead Sea.<ref name=ZoharyHopf3343/>

History

Early human use

Einkorn wheat is one of the earliest cultivated forms of wheat, alongside emmer wheat (T. dicoccum). Hunter gatherers in the Fertile Crescent may have started harvesting einkorn as early as 30,000 years ago, according to archaeological evidence from Syria.<ref>Arranz-Otaegui, A., Carretero, L. G., Ramsey, M. N., Fuller, D. Q., & Richter, T. (2018). "Archaeobotanical evidence reveals the origins of bread 14,400 years ago in northeastern Jordan." Proceedings of the National Academy of Sciences. doi:10.1073/pnas.1801071115</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name=Allaby>Template:Cite journal</ref>

Domestication

Although gathered from the wild for thousands of years, einkorn wheat was first domesticated approximately 10,000 years BP in the Pre-Pottery Neolithic A (PPNA) or B (PPNB) periods.<ref name=ZoharyHopf38>Template:Cite book</ref> Evidence from DNA fingerprinting suggests einkorn was first domesticated near Karaca Dağ in southeast Turkey, an area in which a number of PPNB farming villages have been found.<ref name="Heun1997">Template:Cite journal</ref> One theory by Yuval Noah Harari suggests that the domestication of einkorn was linked to intensive agriculture to support the nearby Göbekli Tepe site.<ref>Template:Cite book</ref>

Spread of cultivation

From the northern part of the Fertile Crescent, the cultivation of einkorn wheat spread to the Caucasus, the Balkans, and central Europe. Einkorn wheat was more commonly grown in cooler climates than emmer wheat, the other domesticated wheat. Cultivation of einkorn in the Middle East began to decline in favor of emmer wheat around 2000 BC. Cultivation of einkorn was never extensive in Italy, southern France, and Spain. Einkorn continued to be cultivated in some areas of northern Europe throughout the Middle Ages and until the early part of the 20th century.<ref name=ZoharyHopf3343>Template:Cite book</ref>

Taxonomy and phylogeny

Cultivated Einkorn was described as a taxon, Triticum monococcum, by Carl Linnaeus in 1753. Later descriptions by other taxonomists, now treated as synonyms, include Triticum pubescens by von Bieberstein in 1800; Triticum hornemanii by Clementi in 1818; Nivieria monococcum in 1841; Triticum vulgare monococcum by Alefeld in 1866; Triticum monococcum subsp. cereale by Albert Thellung in 1918.<ref name="Zaharieva 2014"/> Wild Einkorn is known either as Triticum monococcum subsp. aegilopoides or as Triticum boeoticum.<ref name="Zaharieva 2014"/>

File:Polyploid wheat origins.svg

Einkorn is related to emmer and bread wheat but is not a hybrid.<ref name="Golovnina-2007"/>

Wild and domesticated einkorns are diploid wheats. Unlike emmer and bread wheat, which were formed by hybridisation with Aegilops goatgrasses, einkorn is not a hybrid.<ref name="Golovnina-2007">Template:Cite journal</ref>

Agronomy

Einkorn wheat is low-yielding but can survive on poor, dry, marginal soils where other varieties of wheat will not. It is primarily eaten boiled in whole grains or in porridge.<ref name=ZoharyHopf3343 /> As with other ancient varieties of wheat such as emmer, Einkorn is a "covered wheat" as its kernels do not break free from its seed coat (glume) with threshing. This makes it difficult to separate the husk from the seed.<ref name=Stallknecht>Stallknecht, G. F., Gilbertson, K. M., and Ranney, J.E. (1996), "Alternative Wheat Cereals as Food Grains: Einkorn, Emmer, Spelt, Kamut, and Triticale" in J. Janick, ed., Progress in New Crops, Alexandria, VA: ASHA Press, pp. 156–170</ref>

Food use and nutrition

Einkorn is a common food in northern Provence (France).<ref>Template:Cite book</ref> It is used for bulgur or as animal feed in mountainous areas of countries including France, India, Italy, Morocco, the former Yugoslavia, and Turkey.<ref name=Stallknecht/> It contains gluten (so is not suitable for people with gluten-related disorders<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>) and has a higher percentage of protein than modern red wheats. It is considered more nutritious because it has higher levels of fat, phosphorus, potassium, pyridoxine, and beta-carotene.<ref name=Stallknecht/>

As a resource for plant breeding

Einkorn is the source of many potential introgressions for immunity – Nikolai Vavilov called it an "accumulator of complex immunities."<ref name="Zaharieva 2014">Template:Cite journal</ref> T. monococcum is the source of Sr21, a stem rust resistance gene which has been introgressed into hexaploid worldwide.<ref name = "Concepts-and-Methods" >Template:Cite book</ref> It is also the source of Yr34, a resistance gene for yellow rust.<ref name="Locate rust resistance gene donated from Einkorn">Template:Cite journal</ref>

The salt-tolerance feature of T. monococcum has been bred into durum wheat.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Images

• Usdaeinkorn2.jpg

  From Thuringia, Germany

• Triticum monococcum MHNT.BOT.2015.2.37.jpg

  MHNT

• Wildeinkorn.jpg

  Wild einkorn, Mount Karadağ

• Triticum boeoticum Bajuwarenhof Kirchheim 2012-08-05.jpg
• Associations of wild cereals and other wild grasses in northern Israel.jpg

  Associations of wild cereals and other wild grasses in northern Israel

• Usdaeinkorn1 Triticum monococcum.jpg

  The seeds remain inside the threshed spikelets.

• Leiden University Library - Seikei Zusetsu vol. 17, page 004 - 大麦奴 - Triticum monococcum L., 1804.jpg

  T. monococcum, Japanese agricultural encyclopedia Seikei Zusetsu (1804)