Archaeology. Sedimentary DNA from a submerged site reveals wheat in the British Isles 8000 years ago.

The Mesolithic-to-Neolithic transition marked the time when a hunter-gatherer economy gave way to agriculture, coinciding with rising sea levels. Bouldnor Cliff, is a submarine archaeological site off the Isle of Wight in the United Kingdom that has a well-preserved Mesolithic paleosol dated to 8000 years before the present. We analyzed a core obtained from sealed sediments, combining evidence from microgeomorphology and microfossils with sedimentary ancient DNA (sedaDNA) analyses to reconstruct floral and faunal changes during the occupation of this site, before it was submerged. In agreement with palynological analyses, the sedaDNA sequences suggest a mixed habitat of oak forest and herbaceous plants. However, they also provide evidence of wheat 2000 years earlier than mainland Britain and 400 years earlier than proximate European sites. These results suggest that sophisticated social networks linked the Neolithic front in southern Europe to the Mesolithic peoples of northern Europe.

Emergence of agriculture in the foothills of the Zagros Mountains of Iran.

The role of Iran as a center of origin for domesticated cereals has long been debated. High stratigraphic resolution and rich archaeological remains at the aceramic Neolithic site of Chogha Golan (Ilam Province, present-day Iran) reveal a sequence ranging over 2200 years of cultivation of wild plants and the first appearance of domesticated-type species. The botanical record from Chogha Golan documents how the inhabitants of the site cultivated wild barley (Hordeum spontaneum) and other wild progenitor species of modern crops, such as wild lentil and pea. Wild wheat species (Triticum spp.) are initially present at less than 10% of total plant species but increase to more than 20% during the last 300 years of the sequence. Around 9800 calendar years before the present, domesticated-type emmer appears. The archaeobotanical remains from Chogha Golan represent the earliest record of long-term plant management in Iran.

The paradox of plows and productivity: an agronomic comparison of cereal grain production under Iroquois hoe culture and European plow culture in the seventeenth and eighteenth centuries.

Iroquois maize farmers in the seventeenth and eighteenth centuries produced three to five times more grain per acre than wheat farmers in Europe. The higher productivity of Iroquois agriculture can be attributed to two factors. First, the absence of plows in the western hemisphere allowed Iroquois farmers to maintain high levels of soil organic matter, critical for grain yields. Second, maize has a higher yield potential than wheat because of its C4 photosynthetic pathway and lower protein content. However, tillage alone accounted for a significant portion of the yield advantage of the Iroquois farmers. When the Iroquois were removed from their territories at the end of the eighteenth century, US farmers occupied and plowed these lands. Within fifty years, maize yields in five counties of western New York dropped to less than thirty bushels per acre. They rebounded when US farmers adopted practices that countered the harmful effects of plowing.

Wheat domestication: lessons for the future.

Wheat was one of the first crops to be domesticated more than 10,000 years ago in the Middle East. Molecular genetics and archaeological data have allowed the reconstruction of plausible domestication scenarios leading to modern cultivars. For diploid einkorn and tetraploid durum wheat, a single domestication event has likely occurred in the Karacadag Mountains, Turkey. Following a cross between tetraploid durum and diploid T. tauschii, the resultant hexaploid bread wheat was domesticated and disseminated around the Caucasian region. These polyploidisation events facilitated wheat domestication and created genetic bottlenecks, which excluded potentially adaptive alleles. With the urgent need to accelerate genetic progress to confront the challenges of climate change and sustainable agriculture, wild ancestors and old landraces represent a reservoir of underexploited genetic diversity that may be utilized through modern breeding methods. Understanding domestication processes may thus help identifying new strategies.

Norman Borlaug: the man I worked with and knew.

Much has been written about Norman Borlaug the agricultural scientist and humanitarian whose achievements are recognized with many accolades; to add to those writings is a difficult task. This brief paper is an attempt to provide a personal perspective on Norman Borlaug that can come only from someone who has worked closely with him throughout his professional life. I have endeavored to recollect my early impressions of working with Borlaug as a wheat breeder in Mexico and to highlight his innovative approach to wheat breeding, as well as his views on global population and food security, fertilizers, organic agriculture, biotechnology, and conventional academia. His work ethic was instrumental in his vision for the international agricultural system as an instrument of change in the world. His spirit serves as a reminder to future agricultural scientists that the battle must be vigorously engaged and can be won.

New series for agricultural prices in London, 1770­1914.

New annual series for the prices of major agricultural commodities sold in London markets between 1770 and 1914 are presented. These series are based on bimonthly observations drawn from newspaper market reports. The products covered are wheat, barley (grinding and malting), oats, potatoes, hay, butter, beef, mutton, and pork. Annual prices are calculated for both calendar and production years. The new series are compared to existing series.

Fascist labscapes: geneticists, wheat, and the landscapes of Fascism in Italy and Portugal.

This paper explores the role of scientists in the building of fascist regimes in Italy and Portugal by focusing on plant geneticists' participation in the Italian and Portuguese wheat wars for bread self-sufficiency. It looks closely at the work undertaken by Nazareno Strampelli at the National Institute of Genetics for Grain Cultivation (Italy) and by António Sousa da Câmara at the National Agronomic Experiment Station (Portugal), both of whom took wheat as their prime experimental object of genetics research. The main argument is that the production of standardized organisms­the breeder's elite seeds­in laboratory spaces is deeply entangled with their circulation through extended distribution networks that allowed for their massive presence in Italian and Portuguese landscapes such as the Po Valley and the Alentejo. The narrative pays particular attention to the historical development of fascist regimes in the two countries, advancing the argument that breeders' artifacts were key components of the institutionalization of the new political regimes.

[Allelic diversity at gliadin-coding gene loci in cultivars of spring durum wheat (Triticum durum Desf.) bred in Russia and former Soviet Republics in the 20th century].

Allelic diversity at five gliadin-coding gene loci has been studied in the most important spring durum wheat cultivars released in Russia and former Soviet republics in the 20th century (66 cultivars). Seven, 5, 8, 13, and 2 allelic variants of blocks of gliadin components controlled by the loci Gli-A1d, Gli-B1d, Gli-A2d, Gli-B2d, and Gli-B5d, respectively, have been identified. The allelic diversity did not exhibit a consistent trend during the period studied. Nei's diversity index (H) was 0.68 in the period from 1929 to 1950, increased to 0.70 in 1951-1980, and decreased to 0.58 after the year 1981. It has been found that the most frequent alleles in this collection are relatively rare in other regions of the world, which suggests unique ways of the formation of the diversity of durum wheat cultivars in the former Soviet Union. The efficiency of electrophoresis of storage proteins as a method for identification of durum wheat cultivars by the gliadin electrophoretic pattern has been estimated.

Sir Charles Edward Saunders, Dominion cerealist.

Charles Edward Saunders was born in London, Ontario, in 1867. His father, Sir William Saunders, was the first director of the Dominion Experimental Farms (1886-1911). Charles received his B.A. with honours in science from the University of Toronto in 1888 and his Ph.D. in chemistry from Johns Hopkins University in Baltimore, Maryland, in 1891. He attempted a career in music, his first love, from 1893 to 1902. With his father, Charles attended the 1902 International Conference on Plant Breeding and Hybridization in New York, where he learned of Mendel's theories of inheritance and their applicability to plant breeding. When he began work in 1903 in the Division of Cereal Breeding and Experimentation at the Central Experimental Farm in Ottawa, he used the knowledge he had gained at that conference. It was Charles's goal to achieve "fixity" in the varieties that had been bred and released using phenotypic mass selection, prior to his tenure as Cerealist. He selected four heads from the wheat variety Markham and in the winter of 1904 he performed a "chewing test" to select for gluten elasticity and colour. Seeds from two heads were chosen, and seeds from one went on to produce the variety Marquis after extensive yield trials on the Prairies. Marquis was 7 to 10 days earlier than Red Fife, the standard bread wheat of the Prairies. The earliness and tremendous yield of Marquis wheat resulted in the rapid and successful settlement of the Great Plains and countless billions of dollars in revenue to Canada. By 1923, 90% of the spring wheat in Canada and 70% in the USA was Marquis. Charles continued as Dominion Cerealist until his retirement in 1922. He was knighted in 1934, and died in 1937.

Stable carbon and nitrogen isotopes and quality traits of fossil cereal grains provide clues on sustainability at the beginnings of Mediterranean agriculture.

We present a novel approach to study the sustainability of ancient Mediterranean agriculture that combines the measurement of carbon isotope discrimination (Delta(13)C) and nitrogen isotope composition (delta(15)N) along with the assessment of quality traits in fossil cereal grains. Charred grains of naked wheat and barley were recovered in Los Castillejos, an archaeological site in SE Spain, with a continuous occupation of ca. 1500 years starting soon after the origin of agriculture (ca. 4000 BCE) in the region. Crop water status and yield were estimated from Delta(13)C and soil fertility and management practices were assessed from the delta(15)N and N content of grains. The original grain weight was inferred from grain dimensions and grain N content was assessed after correcting N concentration for the effect of carbonisation. Estimated water conditions (i.e. rainfall) during crop growth remained constant for the entire period. However, the grain size and grain yield decreased progressively during the first millennium after the onset of agriculture, regardless of the species, with only a slight recovery afterwards. Minimum delta(15)N values and grain N content were also recorded in the later periods of site occupation. Our results indicate a progressive loss of soil fertility, even when the amount of precipitation remained steady, thereby indicating the unsustainable nature of early agriculture at this site in the Western Mediterranean Basin. In addition, several findings suggest that barley and wheat were cultivated separately, the former being restricted to marginal areas, coinciding with an increased focus on wheat cultivation.

Historical changes in the concentrations of selenium in soil and wheat grain from the Broadbalk experiment over the last 160 years.

Selenium (Se) intake has decreased substantially in the UK population since 1970s. To investigate whether Se concentration in wheat grain has changed as a result of yield improvement or environmental changes, we analyzed archived wheat grain from the Broadbalk Wheat Experiment at Rothamsted, England, which has been run continuously for over 160 years. Wheat grain and soil samples were selected from plots receiving different fertilizer or manure treatments. Grain Se concentration varied from 11 to 236 ng g(-1), with a mean and median of 44 and 32 ng g(-1), respectively. Grain samples from the unfertilized control plot had significantly higher concentrations of Se than those from fertilized or manured plots; the latter received various amounts of S and also had higher grain yield. No significant trends in grain Se concentrations were detected in the fertilized or manured plots, in spite of a dramatic increase in grain yield since the introduction of modern short-straw cultivars in the mid 1960s. In the control plot, grain samples had higher Se concentrations in the periods before 1920 or after 1970 than those during 1920-1970. This temporal pattern mirrored that of SO(2) emissions and atmospheric S deposition. Soil Se concentrations showed an increasing trend in all plots over 160 years. The results show that the Se concentration of wheat grain from the Broadbalk experiment was influenced by S inputs from fertilizers and atmospheric deposition, and that improving grain yield through plant breeding has not resulted in a significant decrease in grain Se concentration in the fertilized plots.

Association analysis of historical bread wheat germplasm using additive genetic covariance of relatives and population structure.

Linkage disequilibrium can be used for identifying associations between traits of interest and genetic markers. This study used mapped diversity array technology (DArT) markers to find associations with resistance to stem rust, leaf rust, yellow rust, and powdery mildew, plus grain yield in five historical wheat international multienvironment trials from the International Maize and Wheat Improvement Center (CIMMYT). Two linear mixed models were used to assess marker-trait associations incorporating information on population structure and covariance between relatives. An integrated map containing 813 DArT markers and 831 other markers was constructed. Several linkage disequilibrium clusters bearing multiple host plant resistance genes were found. Most of the associated markers were found in genomic regions where previous reports had found genes or quantitative trait loci (QTL) influencing the same traits, providing an independent validation of this approach. In addition, many new chromosome regions for disease resistance and grain yield were identified in the wheat genome. Phenotyping across up to 60 environments and years allowed modeling of genotype x environment interaction, thereby making possible the identification of markers contributing to both additive and additive x additive interaction effects of traits.

[Dynamics of genetic diversity in winter common wheat Triticum aestivum L. cultivars released in Russia from 1929 to 2005].

Genealogical analysis was used to study the dynamics of genetic diversity in Russian cultivars of winter common wheat from 1929 to 2005. The Shannon diversity index of the total set of released cultivars remained almost unchanged, although the number of original ancestors (landraces and genetic lines) increased almost tenfold in the period under study. This was explained in terms of the dependence of the modified Shannon diversity index on two parameters, the number of original ancestors and the mean coefficient of parentage. Significant direct effects were revealed: a positive effect of the former parameter and a negative of the latter. As a result, the increase in the number of original ancestors was compensated by the increase in relatedness of cultivars. Genetic erosion of realized diversity was observed, as a half of Russian landraces were lost. Although the mean coefficient of parentage did not reach its critical value (R = 0.25), cultivars of some regions (Central and Volga-Vyatka) proved to be closely related. A favorable gradual decrease in the mean coefficient of parentage was observed in the past 15 years. A set of modem winter wheat cultivars, which were introduced in the Russian State Catalog from 2002 to 2005, displayed a cluster structure. The overwhelming majority of cultivars formed two clusters originating from Bezostaya 1 (67% of cultivars) and Mironovskaya 808 (31%).

The ripples of "The Big (agricultural) Bang": the spread of early wheat cultivation.

Demographic expansion and (or) migrations leave their mark in the pattern of DNA polymorphisms of the respective populations. Likewise, the spread of cultural phenomena can be traced by dating archaeological finds and reconstructing their direction and pace. A similar course of events is likely to have taken place following the "Big Bang" of the agricultural spread in the Neolithic Near East from its core area in southeastern Turkey. Thus far, no attempts have been made to track the movement of the founder genetic stocks of the first crop plants from their core area based on the genetic structure of living plants. In this minireview, we re-interpret recent wheat DNA polymorphism data to detect the genetic ripples left by the early wave of advance of Neolithic wheat farming from its core area. This methodology may help to suggest a model charting the spread of the first farming phase prior to the emergence of truly domesticated wheat types (and other such crops), thereby increasing our resolution power in studying this revolutionary period of human cultural, demographic, and social evolution.