- Proceedings of the National Academy of Sciences of the United States of America
- Published about 7 years ago
The Near East Fertile Crescent is well recognized as a primary center of barley origin, diversity, and domestication. A large number of wild barleys have been collected from the Tibetan Plateau, which is characterized by an extreme environment. We used genome-wide diversity array technology markers to analyze the genotypic division between wild barley from the Near East and Tibet. Our results confirmed the existence of Tibetan wild barley and suggested that the split between the wild barleys in the Near East and those in Tibet occurred around 2.76 million years ago (Mya). To test the concept of polyphyletic domestication of barley, we characterized a set of worldwide cultivated barley. Some Chinese hulless and six-rowed barleys showed a close relationship with Tibetan wild barley but showed no common ancestor with other cultivated barley. Our data support the concept of polyphyletic domestication of cultivated barley and indicate that the Tibetan Plateau and its vicinity is one of the centers of domestication of cultivated barley. The current results may be highly significant in exploring the elite germplasm for barley breeding, especially against cold and drought stresses.
Dietary recommendations emphasize increased consumption of fruit, vegetables, and whole grain cereals for prevention of chronic disease.
Starch grain, phytolith and cereal bran fragments were analyzed in order to identify the food remains including cakes, dumplings, as well as porridge unearthed at the Astana Cemeteries in Turpan of Xinjiang, China. The results suggest that the cakes were made from Triticum aestivum while the dumplings were made from Triticum aestivum, along with Setaria italica. The ingredients of the porridge remains emanated from Panicum miliaceum. Moreover, direct macrobotantical evidence of the utilization of six cereal crops, such as Triticum aestivum, Hordeum vulgare var. coeleste, Panicum miliaceum, Setaria italica, Cannabis sativa, and Oryza sativa in the Turpan region during the Jin and Tang dynasties (about 3(rd) to 9(th) centuries) is also presented. All of these cereal crops not only provided food for the survival of the indigenous people, but also spiced up their daily life.
Despite the global value of barley, compared to its wild progenitor, genetic variation in this crop has been drastically reduced due to the process of domestication, selection and improvement. In the medium term, this will negatively impact both the vulnerability and yield stability of barley against biotic and abiotic stresses under climate change. Returning to the crop wild relatives (CWR) as sources of new and beneficial alleles is a clear option for enhancing the resilience of diversity and adaptation to climate change. Southeastern Anatolia constitutes an important part of the natural distribution of wild barley in the Fertile Crescent where important crops were initially domesticated. In this study, we investigated genetic diversity in a comprehensive collection of 281 geo-referenced wild barley individuals from 92 collection sites with sample sizes ranging from 1 to 9 individuals per site, collected from southeastern Anatolia and 131 domesticated genotypes from 49 different countries using 40 EST-SSR markers. A total of 375 alleles were detected across entire collection, of which 283 were carried by domesticated genotypes and 316 alleles were present in the wild gene pool. The number of unique alleles in the wild and in the domesticated gene pool was 92 and 59, respectively. The population structure at K = 3 suggested two groups of wild barley namely G1-W consisting wild barley genotypes from the western part and G1-E comprising those mostly from the eastern part of the study area, with a sharp separation from the domesticated gene pool. The geographic and climatic factors jointly showed significant effects on the distribution of wild barley. Using a Latent Factor Mixed Model, we identified four candidate loci potentially involved in adaptation of wild barley to three environmental factors: temperature seasonality, mean temperature of driest quarter, and precipitation of coldest quarter. These loci are probably the targets of genomic regions, with potential roles against abiotic stresses.
Limit dextrinase (LD) is a unique de-branching enzyme involved in starch mobilization of barley grains during malting, and closely related to malt quality. Genotypic variation of LD activity is controlled by genetic factors and also affected by environmental conditions. Correlation analysis between LD activity and four malt quality parameters showed that LD activity was positively correlated with diastatic power, Kolbach index and the quality of malt extract, while negatively correlated with viscosity. The structure-based association analysis demonstrated that HvLDI, a gene encoding limit dextrinase inhibitor, was a major determinant of LD activity and malt quality. The single nucleotide polymorphisms associated with LD activity could be used in early generation selection for barley breeding.
Copper (Cu) containing fungicides have been used for more than one century in Europe on agricultural soils, such as vineyard soils. Total Cu concentrations in such soils can exceed toxicological limits that are commonly derived using artificially spiked soils. This study surveyed Cu toxicity in vineyard soils with reference to soils spiked with CuCl(2). Soil was collected in six established European vineyards. At each site, samples representing a Cu concentration gradient were collected. A control (uncontaminated) soil sampled nearby the vineyard was spiked with CuCl(2). Toxicity was tested using standard ecotoxicity tests: two plant assays (Lycopersicon esculentum Miller (tomato) and Hordeum vulgare L. (barley) growth), one microbial assay (nitrification) and one invertebrate assay (Enchytraeus albidus reproduction). Maximal total Cu concentrations in the vineyard sites ranged 435-690mgCukg(-1), well above the local background (23-105mgCukg(-1)). Toxicity in spiked soils (50% inhibition) was observed at added soil Cu concentrations from 190 to 1039mgCukg(-1) (mean 540mgCukg(-1)) depending on the assay and the site. In contrast, significant adverse effects were only found for three bioassays in vineyard samples of one site and for two bioassays in another site. Biological responses in these cases were more importantly explained by other soil properties than soil Cu. Overall, no Cu toxicity to plants, microbial processes and invertebrates was observed in vineyard soil samples at Cu concentrations well above European Union limits protecting the soil ecosystem.
A maltotetraose-producing enzyme (G4-amylase) was utilized to improve the baking performance of whole-grain wheat flour. Whole-grain bread dough prepared with G4-amylase showed reduced water absorption and increased development time, while the dough stability was not affected. Also, the G4-amylase-treated samples exhibited lower Mixolab torque values than the control upon heating and cooling. Rheological measurements showed the decreased ratio of Rmax /E and increased tan δ, clearly demonstrating that the viscous characteristics of whole-grain bread dough became dominant with increasing levels of G4-amylase. The use of G4-amylase produced whole-grain wheat breads with a variety of maltooligosaccharides, primarily maltotetraose that positively contributed to the bread volume (1.2-fold higher than the control). Moreover, G4-amylase delayed the crumb firming of whole-grain wheat bread during a 7-d storage period, showing that it can function as an antiretrogradation agent to enhance the quality attributes of whole-grain wheat bread.
Beer is a popular alcoholic malt beverage resulting from a fermentation of the aqueous extract of malted barley with hops. The aroma of brewing barley impacts on the flavor of beer indirectly because some flavor compounds or their precursors in beer came from the barley. The objectives of this research were to study volatile profiles and to characterize odor-active compounds in brewing barley in order to find out the variability of the aroma composition among different brewing barley cultivars.
Today, farmers in many regions of eastern Asia sow their barley grains in the spring and harvest them in the autumn of the same year (spring barley). However, when it was first domesticated in southwest Asia, barley was grown between the autumn and subsequent spring (winter barley), to complete their life cycles before the summer drought. The question of when the eastern barley shifted from the original winter habit to flexible growing schedules is of significance in terms of understanding its spread. This article investigates when barley cultivation dispersed from southwest Asia to regions of eastern Asia and how the eastern spring barley evolved in this context. We report 70 new radiocarbon measurements obtained directly from barley grains recovered from archaeological sites in eastern Eurasia. Our results indicate that the eastern dispersals of wheat and barley were distinct in both space and time. We infer that barley had been cultivated in a range of markedly contrasting environments by the second millennium BC. In this context, we consider the distribution of known haplotypes of a flowering-time gene in barley, Ppd-H1, and infer that the distributions of those haplotypes may reflect the early dispersal of barley. These patterns of dispersal resonate with the second and first millennia BC textual records documenting sowing and harvesting times for barley in central/eastern China.
Crop production and yield estimation using remotely sensed data have been studied widely, but such information is generally scarce in arid and semi-arid regions. In these regions, inter-annual variation in climatic factors (such as rainfall) combined with anthropogenic factors (such as civil war) pose major risks to food security. Thus, an operational crop production estimation and forecasting system is required to help decision-makers to make early estimates of potential food availability. Data from NASA’s MODIS with official crop statistics were combined to develop an empirical regression-based model to forecast winter wheat and barley production in Iraq. The study explores remotely sensed indices representing crop productivity over the crop growing season to find the optimal correlation with crop production. The potential of three different remotely sensed indices, and information related to the phenology of crops, for forecasting crop production at the governorate level was tested and their results were validated using the leave-one-year-out approach. Despite testing several methodological approaches, and extensive spatio-temporal analysis, this paper depicts the difficulty in estimating crop yield on an annual base using current satellite low-resolution data. However, more precise estimates of crop production were possible. The result of the current research implies that the date of the maximum vegetation index (VI) offered the most accurate forecast of crop production with an average R(2)=0.70 compared to the date of MODIS EVI (Avg R(2)=0.68) and a NPP (Avg R(2)=0.66). When winter wheat and barley production were forecasted using NDVI, EVI and NPP and compared to official statistics, the relative error ranged from -20 to 20%, -45 to 28% and -48 to 22%, respectively. The research indicated that remotely sensed indices could characterize and forecast crop production more accurately than simple cropping area, which was treated as a null model against which to evaluate the proposed approach.