How was wheat domesticated during the agricultural revolution

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It was a key event in the agricultural revolution that occurred about 10,000 years ago in the Fertile Crescent of the Middle East. Transitions of forms with natural seed dispersal mechanisms to forms with non-brittle rachises led to the domestication of diploid einkorn and tetraploid emmer wheat in southeast Turkey.

In the second phase of cultivation, domesticated forms consisting of einkorn and emmer wheat were grown by early farmers. These wheats acquired a non-brittle rachis, which allowed early farmers to efficiently harvest the grain without the spikes shattering and falling to the ground before harvest.Nov 7, 2013

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Answer

What is the history of wheat domestication?

However, the domestication history for wheat is more complex. Hexaploid bread wheat ( Triticum aestivum L. ssp. aestivum) derives its three genomes (A, B and D) from three diploid wild ancestors: Triticum urartu Tumanian ex Gandylian, an unknown relative of Aegilops speltoides Tausch and Ae. tauschii Coss, respectively.

How did farmers harvest wheat after it was ripe?

One possible way that might have occurred is that farmers harvested wheat after it was ripe, but before it self-dispersed, thereby collecting only the wheat that was still attached to the plant. By planting those seeds the next season, the farmers were perpetuating plants that had later-breaking rachises.

What culture brought wheat from Asia to Europe?

The culture generally associated with the introduction of wheat and other crops from Asia to Europe is generally the Lindearbandkeramik (LBK) culture, which may have been made up of part immigrant farmers and part local hunter-gatherers adapting new technologies. LBK is typically dated in Europe between 5400–4900 BCE.

What genes are involved in the domestication of wheat?

Free-threshing grain is another important domestication trait and is controlled by at least two groups of genes in wheat, the Tenacious glumes ( Tg) genes and the Q locus on chromosome 5A.

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How was wheat domesticated?

Wheat was domesticated ten thousand years ago in the present-day Middle East, when humans rapidly modified the crop’s key traits. Nowadays, we continue to produce domestic wheat.


When did wheat become domesticated?

around 10,000 years agoCorresponding author. The domestication of wheat around 10,000 years ago marked a dramatic turn in the development and evolution of human civilization, as it enabled the transition from a hunter-gatherer and nomadic pastoral society to a more sedentary agrarian one.


Did we domesticate wheat or did wheat domesticate us?

We did not domesticate wheat. It domesticated us. The word ‘domesticate’ comes from the Latin domus, which means ‘house’.


Where did domesticated wheat come from?

The origins of our modern wheat, according to genetics and archaeological studies, are found in the Karacadag mountain region of what is today southeastern Turkey—emmer and einkorn wheats are two of the classic eight founder crops of the origins of agriculture.


How did wheat become cultivated?

More than 17,000 years ago, humans gathered the seeds of plants and ate them. After rubbing off the husks, early people simply chewed the kernels raw, parched or simmered. Wheat originated in the “cradle of civilization” in the Tigris and Euphrates river valley, near what is now Iraq.


Was wheat the first domesticated crop?

Einkorn wheat The crop is among the first eight crops to be domesticated and cultivated.


Has America domesticated wheat?

We did not domesticate wheat. It domesticated us. The word “domesticate” comes from the Latin domus, which means “house.” Who’s the one living in a house?


What does Harari mean when he suggests that wheat domesticated humans?

The fraudsters, in Harari’s telling, were wheat, rice, potatoes and a few other plants, who “domesticated Homo sapiens, rather than vice versa.” That is, by allowing themselves to be domesticated, which many other plants refused to do, these plants tricked human beings into spreading their genes, turning the plants …


Who domesticated man?

A new study—citing genetic evidence from a disorder that in some ways mirrors elements of domestication—suggests modern humans domesticated themselves after they split from their extinct relatives, Neanderthals and Denisovans, approximately 600,000 years ago.


Where and when wheat was first domesticated and what people first domesticated it?

The earliest known emmer wheat dates back to 8500 b.c. and came from a region in the near Middle East, called the “Fertile Crescent.” After its domestication there, it spread further west, to Greece in 6500 b.c. and Germany in 5000 b.c. Perhaps the most widely used wheat, bread wheat (dated to 6000 b.c.), is strictly a …


Who domesticated wheat and barley?

humansEinkorn and emmer wheat together with barley were among the first cereals domesticated by humans more than 10,000 years ago, long before durum or bread wheat originated. Domesticated einkorn wheat differs from its wild progenitor in basic morphological characters such as the grain dispersal system.


What are characteristics of domesticated wheat?

Other domestication-related and crop evolution traits include: glume reduction (easier threshing), changes in plant architecture, changes in ear and kernel size, loss of seed dormancy, lower grain protein and mineral concentrations, and increased grain carbohydrate content (Harlan et al., 1973). Fig.


When was wheat first domesticated?

Wheat was domesticated ten thousand years ago in the present-day Middle East, when humans rapidly modified the crop’s key traits.


What is the purpose of the study of wild emmer wheat?

Their work analyses the genome of wild emmer wheat to better link the grain’s physical traits to the genes responsible for them. They found two main genes responsible for shattering spikes in wild wheat—two genes that are not functional in domesticated wheat.


How much of the world’s calories are from wheat?

Wheat is an essential part of diets around the globe: in fact, twenty percent of the world’s total calorie consumption is from wheat alone.


Is wheat over genetics?

But modifications to wheat may not be over, especially with these new genetic discoveries. “Now that wheat is in the ‘post-genomic era,’ many scientists will feel comfortable working on wheat instead of model plants, so wheat improvement will be faster,” Distelfeld said.


What two crops were the founders of the agricultural revolution?

Abstract. Wheat and barley are two of the founder crops of the agricultural revolution that took place 10,000 years ago in the Fertile Crescent and both crops remain among the world’s most important crops.


Where is wheat grown?

Modern wheat is grown as far north as the Arctic Circle and as far south as 41 ° S in Chile ( fao.org ). Barley has a similar range ( croptrust.org ).


What genes control wheat?

Baking quality in wheat is controlled by genes known as prolamins (gliadins and glutenins) (Payne 1987 ). A recent assembly of the bread wheat genome (Clavijo et al. 2017) identified all previously known gluten genes, corrected 21 of these genes and identified an additional 33 genes.


Where did barley come from?

Archaeological and genetic evidence suggest that one of the origins of barley and wheat could have been the Fertile Crescent, specifically in the Israel-Jordan area in the Fertile Crescent (Badr et al. 2000 ).


When did wheat and barley start?

Wheat and barley are two of the founding crops that started the agricultural revolution about 10,000 years ago in the Fertile Crescent (Zohary et al. 2012 ). In fact, many of the wild progenitors of these crops still exist in this region (Harlan and Zohary 1966 ).


Is spelt more primitive than bread wheat?

Since spelt is not free-threshing, it can be considered to be more primitive than free-threshing bread wheat, at least from an anthropocentric view. Two genes are important for the free-threshing character: tenacious glumes ( Tg) and the domestication locus Q (which also affects other domestication traits).


What were the two founder crops of the agricultural revolution?

Wheat and barley are two of the founder crops of the agricultural revolution that took place 10,000 years ago in the Fertile Crescent and both crops remain among the world’s most important crops. Domestication of these crops from their wild ancestors required the evolution of traits useful to humans …. Wheat and barley are two of the founder crops …


What traits are most pronounced between wild and domesticated crops?

Of these traits, grain retention and threshability, yield improvement, changes to photoperiod sensitivity and nutritional value are most pronounced between wild and domesticated forms.


What are the genetic mutations in wheat?

Genetic mutations in genes governing wheat threshability were critical for domestication. Knowing when these genes mutated during wheat evolution will provide more insight into the domestication process and lead to further exploitation of primitive alleles for wheat improvement. We evaluated a population of recombinant inbred lines derived from a cross between the durum variety Rusty and the cultivated emmer accession PI 193883 for threshability, rachis fragility, and other spike-related traits. Quantitative trait loci (QTL) associated with spike length, spikelets per spike, and spike compactness were primarily associated with known genes such as the pleiotropic domestication gene Q. Interestingly, rachis fragility was not associated with the Q locus, suggesting that this trait, usually a pleiotropic effect of the q allele, can be influenced by the genetic background. Threshability QTL were identified on chromosome arms 2AS, 2BS, and 5AL corresponding to the tenacious glume genes Tg2A and Tg2B as well as the Q gene, respectively, further demonstrating that cultivated emmer harbors the primitive non-free-threshing alleles at all three loci. Genetic analysis indicated that the effects of the three genes are mostly additive, with Q having the most profound effects on threshability, and that free-threshing alleles are necessary at all three loci to attain a completely free-threshing phenotype. These findings provide further insight into the timeline and possible pathways of wheat domestication and evolution that led to the formation of modern day domesticated wheats.


Where is durum wheat grown?

Durum wheat (Triticum turgidum L. subsp. durum (Desf.) van Slageren) is an important crop in the Mediterranean Rim, and it is deeply rooted in the history and tradition of this region. Recently, several studies that examined DNA markers on Mediterranean landrace collections have successfully elucidated the pathways of this crop across the Mediterranean Rim, but the historical frame is still rather diffuse. This paper aims at tracing the historical evolution of durum wheat throughout the Mediterranean Rim since its commencement as a crop until present times. A search was carried out through archaeological references where durum wheat remains were found. Historical descriptions about cultivation of this crop, references to products made from its grain, and articles interpreting DNA marker information from Mediterranean landraces were also consulted. The present article also examines the currently available durum wheat genetic resources. Durum wheat was domesticated in the Levant area. Phoenicians, Greeks, and above all Romans were active in the expansion and success of durum cultivation in all Mediterranean Rim that started displaced emmer by the mid first millennium BCE. Early Arab empire expanded in the area of durum wheat cultivation promoting food types based on semolina (dry pasta and couscous). Up to 1955 most durum areas in this area were planted with landraces, but several breeding programs were initiated in Italy, and later at CIMMYT and at ICARDA. Landrace collection and conservation efforts were carried out along the Mediterranean Rim countries to preserve the legacy of this crop.


What are the challenges of durum wheat?

The productivity of durum wheat [Triticum turgidum subsp. durum (Desf.) van Slageren] is affected by drought and/or high temperatures, challenges to be amplified by climate change. Pre-breeding using wild relatives can supply useful traits for durum wheat improvement to adapt to major abiotic and biotic stresses. Sixty-seven lines issued from backcrosses of Cham5 and Haurani durum wheat varieties with accessions of Triticum aegilopoides (Link) Bal. ex Koern., T. dicoccoides Koern. ex Schweinf., T. urartu Thumanian ex Gandilyan, and Aegilops speltoides Tausch were evaluated for drought and heat tolerance. The trials were conducted during two seasons (2016−2017 and 2017–2018) at Tessaout, Morocco, under full irrigation (optimal conditions) and rainfed conditions (drought stressed) and at Wed Medani, Sudan, under full irrigation combined with heat stress. The recurrent parents, along with eight best cultivars and elite breeding lines, were used as checks. Drought reduced the grain yield by 62%. Grain yield and drought tolerance index were used to identify lines to be used by breeding programs to enhance drought and heat tolerance. The derivatives lines 142014 (Cham5*3/T. aegilopoides), 142074 (Cham5*3/T. dicoccoides), and 142015 along with the checks Icarachaz and Gidara 2 ranked among the best under heat stress. Under drought stress, the lines 141972 (Haurani*2/T. urartu) and 141973 (Cham5*2/T. dicoccoides) yielded 196 and 142% of their recurrent parents’ yield, respectively. High variation was found for agronomic and phenology traits, with heading time explaining 16% of grain yield under drought, while thousand kernel weight accounted for 18% of the yield under heat. We conclude that gene introgression from wild relatives pays off and can increase wheat resilience to cope with climate change effects. © 2020 The Authors. Crop Science


What are the most important food sources for humans?

Crop production and natural resource use, especially in developing countries, represents one of the most important food sources for humans. In particular, two wheat species (tetraploid, which is mostly used for pasta and hexaploid, which is primarily used for bread) account for about 20% of the whole calories consumed worldwide. In order to assess the mineral accumulation capability of some popular tetraploid wheat genotypes, a metabolomic (metallomic) approach was used in this study. The metallomic profile related to micro- (Zn, Fe, Cu, Mn, Ni and Cr), macro- (Ca, Mg and K) and toxic trace elements (Cd and Pb) was obtained by ICP-AES analysis in a large set of tetraploid wheat genotypes (Triticum turgidum L.) that were grown in two different experimental fields. Correlations and multivariate statistical analyses were performed, grouping the samples under two wheat sets, comprising cultivated durum cultivars (T. turgidum subsp. durum) and wild accessions (T. turgidum subsp. dicoccum and subsp. dicoccoides). The site dependence ranking for the selected genotypes with the highest nutrient accumulation was obtained. The significantly higher content of Mg (among the macronutrients) and the highest levels of Mn, Fe and Zn (among the micronutrients) were found for wild accessions with respect to durum cultivars. Moreover, the former genotypes were also the ones with the lowest level of accumulation of the trace toxic elements, in particular Cd. According to the performed statistical analyses, the wild accessions appeared also to be less influenced by the different environmental conditions. This is in accord with literature data, indicating the superiority of “old” with respect to modern wheat cultivars for mineral content. Although further studies are required on a wider range of genotypes to confirm these findings, the obtained results could be used to better select the less demanding and better performing cultivars in specific target wheat growing environments.


What are SAPs in wheat?

Stresses associated proteins (SAPs), a fast emerging class of zinc-finger proteins (ZFPs), are composed of special types (A20/AN1) of ZFP domains and were identified for the first time in rice as products of multiple stress responsive genes. SAPs are potential candidates for biotechnological approaches in order to improve abiotic stress tolerance in plants-the ultimate aim of which is crop-yield protection. In wheat there is a member of the stress association protein (SAP) gene family, named TaSAP1-A1 (located on chromosome 7A), involved in response to several abiotic stresses including drought, salt and cold. We analysed 33 European winter wheat cultivars using the markers T7AM5, T7AM2606 and T7AM39, developed by Chang et al. (2013), and located in the promoter region of TaSAP1-A1 gene. Compared to Chang study, our analysis revealed different sizes for the PCR products obtained with T7AM5 and T7AM2606 markers. Furthermore, digestion of PCR product obtained with T7AM5 marker revealed the existence of a new allelic variant (present in four cultivars). Results showed that Hap II is the main haplotype, present in 18 cultivars (55%). Hap II was found to be significantly associated (p<0.05) with thousand kernel weight (TKW). © 2018, National Agricultural Research and Development Institute. All rights reserved.


Is Triticum boeoticum wild?

The status of Triticum boeoticum subsp. aegilopoides (Link) Schiem. is somehow confusing, suggesting a need to verify whether this subspecies is a truly wild or a feral form. After reviewing some rather inaccessible older literature, a half-diallel of three pure einkorn lines (truly wild, domesticated and aegilopoides) was performed. The F2 and F3 analyses of brittleness and microscope-based studies of the abscission scars on rachis fragments were combined with extant genome maps. Two QTL segregated in the cross domesticated × wild (one on chromosome 4 and one on chromosome 7), but only one segregated in the cross feral × wild (same as before on chromosome 7), indicating that the feral form carried a wild (or equivalent) allele. Within the cross domesticated × feral, quantitative segregation occurred and could be caused by some neat abscission scars, but without the typical ‘fish-mouth-like’ appearance of the truly wild form. We suggest that aegilopoides and domesticated einkorn emerged in patches of semi-brittle mutants in the Karacadağ Mountains and were collected and maintained by humans. When agriculture moved from South-East Turkey into Western Turkey and later into the Balkans, aegilopoides became the feral form we know today, characterized by a semi-brittle rachis that makes it less wild compared to the truly wild Triticum boeoticum subsp. thaoudar (Reut. ex Hausskn.) Grossh.


How do plants modulate the soil microbiome?

Plants modulate the soil microbiota by root exudation assembling a complex rhizosphere microbiome with organisms spanning different trophic levels. Here, we assessed the diversity of bacterial, fungal and cercozoan communities in landraces and modern varieties of wheat. The dominant taxa within each group were the bacterial phyla Proteobacteria, Actinobacteria and Acidobacteria; the fungi phyla Ascomycota, Chytridiomycota and Basidiomycota; and the Cercozoa classes Sarcomonadea, Thecofilosea and Imbricatea. We showed that microbial networks of the wheat landraces formed a more intricate network topology than that of modern wheat cultivars, suggesting that breeding selection resulted in a reduced ability to recruit specific microbes in the rhizosphere. The high connectedness of certain cercozoan taxa to bacteria and fungi indicated trophic network hierarchies where certain predators gain predominance over others. Positive correlations between protists and bacteria in landraces were preserved as a subset in cultivars as was the case for the Sarcomonadea class with Actinobacteria. The correlations between the microbiome structure and plant genotype observed in our results suggest the importance of top-down control by organisms of higher trophic levels as a key factor for understanding the drivers of microbiome community assembly in the rhizosphere.


Why did humans need to cultivate wheat?

It required hard work to cultivate wheat. Human beings began to have more children to use as extra labor to harvest the wheat, which in turn created more mouths to feed, which increased the demand for wheat and perpetuate overpopulation that continues today.


How has wheat changed the world?

Many would say wheat saves human existence. Wheat became a stable and reliable food source that allowed a human being to grow cities and modern culture.


How does agriculture affect the environment?

Agriculture alters both the animals and plants it domesticates. Ultimately, it changes the very landscape itself. The growing of a single crop in a field by definition substitutes a biological monoculture for the complex ecological system that existed on the same ground previously. This change has several effects.


What are the unintended effects of crop growing?

Unwittingly, they are also “selecting for” any organism that can live on wheat: wheat-eating “vermin,” pathogens, and diseases of wheat, etc.


Can growing crops deplete soil?

Over a relatively short period of time, growing a single crop can deplete even very rich soil. This was a problem which rendered many early agricultural sites uninhabitable after a time. It is still a very serious problem. There are other unintended effects of crop-growing.

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