Grains from ear to ear: the morphology of spelt and free-threshing wheat from Roman Mursa (Osijek), Croatia

Cereals were a significant part of the Roman diet, yet knowledge about their cultivation, distribution and consumption in certain regions is particularly lacking. In Europe, studies generally suggest that from the Iron Age to the Roman period there was a reduction in barley cultivation, an increase in spelt over emmer, a preference for free-threshing wheat over glume wheats, as well as the increased cultivation of rye and oats. Up till now, there was little evidence on crop cultivation in Croatia, but the discovery of around 24,000 cereal grains from the oven of a 2nd-4th c. ad Roman villa in the modern town of Osijek provides important insights into diet and subsistence in the Roman province of Pannonia. Here, the dominance of free-threshing wheat, spelt and rye with only a relatively small amount of other cereals, chaff and weeds corresponds well with this pattern seen elsewhere in Europe. The relatively clean grain deposit suggests that this sample represents processed grain ready for final food preparation and consumption at the villa. The morphological variation and overlap seen between the carbonised spelt and free-threshing wheat grains, as well as the identification of ‘stunted’ cereal grains, is also discussed.

     

Differential response of rye,triticale, bread and durum wheats to zinc deficiency in calcareous soils

Field and greenhouse experiments were carried out to study the response of rye (Secale cereale L. cv. Aslim), triticale (× Triticosecale Wittmark. cv. Presto), two bread wheats (Triticum aestivum L, cvs. Bezostaja-1 and Atay-85) and two durum wheats (Triticum durum L. cvs. Kunduru-1149 and C-1252) to zinc (Zn) deficiency and Zn fertilization in severely Zn-deficient calcareus soils (DTPA-Zn=0.09 mg kg^-1 soil). The first visible symptom of Zn deficiency was a reduction in shoot elongation followed by the appearance of whitish-brown necrotic patches on the leaf blades. These symptoms were either absent or only slight in rye and triticale, but occurred more rapidly and severely in wheats, particularly in durum wheats. The same was true for the decrease in shoot dry matter production and grain yield. For example, in field experiments at the milk stage, decreases in shoot dry matter production due to Zn deficiency were absent in rye, and were on average 5% in triticale, 34% in bread wheats and 70%, in durum wheats. Zinc fertilization had no effect on grain yield in rye but enhanced grain yield of the other cereals. Zinc efficiency of cereals, expressed as the ratio of yield (shoot dry matter or grain) produced under Zn deficiency compared to Zn fertilization were, on average, 99% for rye, 74% for triticale, 59% for bread wheats and 25% for durum wheats.These distinct differences among and within the cereal species in susceptibility to Zn deficiency were closely related to the total amount (content) of Zn per shoot, but not with the Zn concentrations in shoot dry matter. For example, the most Zn-efficient rye and the Zn-inefficient durum wheat cultivar C-1252 did not differ in shoot Zn concentration under Zn deficiency, but the total amount of Zn per whole shoot was approximately 6-fold higher in rye than the durum wheat. When Zn was applied, rye and triticale accumulated markedly more Zn both per whole shoot and per unit shoot dry matter in comparison to wheats.The results demonstrate an exceptionally high Zn efficiency of rye and show that among the cereals studied Zn efficiency declines in the order rye>triticale>bread wheat>durum wheat. The differences in expression of Zn efficiency are possibly related to a greater capacity of efficient genotypes to acquire Zn from the soil compared to inefficient genotypes.     

Molecular characterization and functional analysis of elite genes in wheat and its related species

The tribe Triticeae includes major cereal crops (bread wheat, durum wheat, triticale, barley and rye), as well as abundant forage and lawn grasses. Wheat and its wild related species possess numerous favourable genes for yield improvement, grain quality enhancement, biotic and abiotic stress resistance, and constitute a giant gene pool for wheat improvement. In recent years, significant progress on molecular characterization and functional analysis of elite genes in wheat and its related species have been achieved. In this paper, we review the cloned functional genes correlated with grain quality, biotic and abiotic stress resistance, photosystem and nutrition utilization in wheat and its related species.     

Genetic variations in the digestibility in sheep of selected whole-crop cereals used as silages

Whole-plant winter cereals could be of great interest if used as silages for ruminant feeding as opposed to summer crops in that they would spare water resources or valorize low-input management. This study aimed to compare the feeding value of rye, barley, wheat (two genotypes) and triticale (six genotypes). The cereals were sown in October and harvested as silage in June. Forages were offered to Texel castrated sheep in order to evaluate the organic matter digestibility (OMd). The OMd of the wheat cultivars was higher (61.6%, P<0.05) than those of barley (57.2%) and rye (54.7%) but no different from that of triticale (60.6%). Within the triticale genotypes, OMd ranged from 54.7 to 62.3%. The presence of rough barbs should explain the relatively low intake of the cereals with the exception of wheat. Winter cereals provide good-quality forage for feeding ruminants. Wheat has a higher nutritional value than barley and rye and a wide variability for digestibility seems to exist within the triticale cultivars. Such variability in a species known for its ability to be cropped under limiting conditions should be explored in much greater depth as it could result in providing farmers with genotypes of good quality with an acceptable yield at a lower cost.     

Medical nutrition therapy: use of sourdough lactic acid bacteria as a cell factory for delivering functional biomolecules and food ingredients in gluten free bread

Celiac disease (CD) is an immune-mediated disease, triggered in genetically susceptible individuals by ingesting gluten from wheat, rye, barley, and other closely related cereal grains. Currently, the estimated prevalence of CD is around 1 % of the population in the western world and medical nutritional therapy (MNT) is the only accepted treatment for celiac disease. To date, the replacement of gluten in bread presents a significant technological challenge for the cereal scientist due to the low baking performance of gluten free products (GF). The increasing demand by the consumer for high quality gluten-free (GF) bread, clean labels and natural products is rising. Sourdough has been used since ancient times for the production of rye and wheat bread, its universal usage can be attributed to the improved quality, nutritional properties and shelf life of sourdough based breads. Consequently, the exploitation of sourdough for the production of GF breads appears tempting. This review will highlight how sourdough LAB can be an efficient cell factory for delivering functional biomolecules and food ingredients to enhance the quality of gluten free bread.     

Monitoring of deoxynivalenol and zearalenone in cereals and cereal products from the state of Saxony-Anhalt,Germany

A Fusarium and Fusarium toxin monitoring programme has been established within the food and feed control authorities of Saxony-Anhalt for the 2001–2003 period. The first results of the deoxynivalenol analyses of cereals and cereal products with assured origin in this federal state, showed a contamination rate of 42% for wheat and wheat products. The contamination incidence reached only 14% in rye and rye products. Zearalenone couldn't be detected at all in the analyzed samples.     

Future utilization of cereal crops

Estimates made on the uses for cereals (corn, wheat, oats, barley, sorghum, rice, and rye) in 1975 are based upon a number of assumptions. If those made in this article are approached, the pattern of cereal use will be much the same as it is at present.     

Earlier onset of DNA fragmentation in leaves of wheat compared to barley and rye

We have found extensive nucleosomal fragmentation of native DNA extracted from leaves of healthy cereal plants, as indicated by ladder patterns on agarose gels and TUNEL staining. The time of first appearance of fragmentation differed among cereals. Native DNA from the first leaf of 10-day-old plants formed a clear ladder pattern of multiples of 180 bp fragments in wheat and triticale but not in barley and oats. In one cultivar of rye a weak ladder pattern occurred but not in another. Freezing and thawing of samples before DNA extraction resulted in much more extensive DNA fragmentation in wheat but not in rye and barley, indicating that DNA-degrading enzymes are present in the cytoplasm of wheat, but not in barley and rye, at this stage. In barley, nucleosomal fragmentation was first detected in 25-day-old plants. These results indicate that programmed cell death takes place in developing leaves of young cereal plants, but that the time of onset differs among cereal species.     

T-2 and HT-2 toxin analysis in cereals and cereal products following IAC cleanup and determination via GC-ECD after derivatization

The authors present a new and sensitive method for the determination of T-2- und HT-2 Toxin in cereals and cereal products in the low ppb level. A representative part of the cereal sample is extracted with a mixture of methanol-water (90:10) and the extract is cleaned on the commercially available immunoaffinity column T-2test™ (IAC), eluted with methanol, derivatized by pentafluorpropionic anhydride (PFPA) and measured on a GC-ECD. The method has been successfully validated on wheat, rye and oats. The recovery rates with wheat and rye endowed on a level of 50 ppb and with 85 ppb naturally contaminated oats were 71–115% with a coefficient of variation of 5.7–19.5%. The detection limits of the method with a signal to noise level of 3:1 were 1.5–2.3 μg/kg for HT-2 and 1.1–1.7 μg/kg for T-2 toxin. Financial support: Federal Ministry of Food and Agriculture (part of the project 05HS 001 — Improvement and validation of type A trichothecene (T-2 toxin and HT-2 toxin) analysis and occurrence of these mycotoxins in food marketed in Germany)     

Induction of recombination between rye chromosome 1RL and wheat chromosomes

Summary The ph1b mutant in bread wheat has been used to induce homoeologous pairing and recombination between chromosome arm 1RL of cereal rye and wheat chromosome/s. A figure of 2.87% was estimated for the maximal frequency of recombination between a rye glutelin locus tightly linked to the centromere and the heterochromatic telomere on the long arm of rye chromosome 1R in the progeny of ph1b homozygotes. This equates to a gametic recombination frequency of 1.44%. This is the first substantiated genetic evidence for homoeologous recombination between wheat and rye chromosomes. No recombinants were confirmed in control populations heterozygous for ph1b. The ph1b mutant was also observed to generate recombination between wheat homoeologues.     

Can spelt wheat be used as heterotic group for hybrid wheat breeding?

Key message

Spelt wheat is a distinct genetic group to elite bread wheat, but heterosis for yield and protein quality is too low for spelt to be recommended as heterotic group for hybrid breeding in wheat.

Abstract

The feasibility to switch from line to hybrid breeding is currently a hot topic in the wheat community. One limitation seems to be the lack of divergent heterotic groups within wheat adapted to a certain region. Spelt wheat is a hexaploid wheat that can easily be crossed with bread wheat and that forms a divergent genetic group when compared to elite bread wheat. The aim of this study was to investigate the potential of Central European spelt as a heterotic group for Central European bread wheat. We performed two large experimental field studies comprising in total 43 spelt lines, 14 wheat lines, and 273 wheat–spelt hybrids, and determined yield, heading time, plant height, resistance against yellow rust, leaf rust, and powdery mildew, as well as protein content and sedimentation volume. Heterosis of yield was found to be lower than that of hybrids made between elite wheat lines. Moreover, heterosis of the quality trait sedimentation volume was negative. Consequently, spelt wheat does not appear suited to be used as heterotic group in hybrid wheat breeding. Nevertheless, high combining abilities of a few spelt lines with elite bread wheat lines make them interesting resources for pre-breeding in bread wheat. Thereby, the low correlation between line per se performance and combining ability of these spelt lines shows the potential to unravel the breeding value of genetic resources by crossing them to an elite tester.

     

Cytosine methylation and nucleolar dominance in cereal hybrids

In wheat-rye hybrids the nucleolus organizer regions (NORs), the sites of ribosomal RNA genes, from rye are suppressed. Wheat and wheat-rye hybrid genetic stocks containing different numbers of wheat and rye nucleolus organizers, as well as addition lines and rye-barley hybrids, were used in Southern hybridization experiments to determine the cause of nucleolar dominance and suppression in cereal hybrids. Based on the use of restriction endonucleases that cleave near the ends of the spacer unit and an additional, methylation-sensitive enzyme, HpaII, which does not recognize the CCGG restriction site if the internal C is methylated, an indirect method of assaying NOR expression was established. The results indicated that cleavage by the HpaII enzyme of the rye NOR sequences, is reduced when major NORs from other cereals were present. The reduction in the number of rye rRNA genes containing an unmethylated CCGG site in the promoter was associated with the suppression of the rye nucleolus. These results are consistent with a model in which promoter and upstream regulatory repeats of ribosomal RNA genes compete for limited concentrations of regulatory proteins, and genes that are methylated at key binding sites fail to engage these regulatory proteins and thus remain inactive. Received: 15 November 1996 / Accepted: 19 March 1997     

Nutrition and environment in medieval Serbia: charred cereal, weed and fruit remains from the fortress of Ras

This study presents the results of archaeobotanical examination of remains from the medieval complex of Ras in Serbia. The samples were collected from the fortress situated on the hilltop (Gradina) and from a settlement below (Podgradje) during the archaeological excavations of 1972–1984. They were taken primarily from the buildings containing charred cereals dating to the 12th and 13th centuries. The main staple was bread wheat, followed by rye. Grains of barley, oats, and millet were also present. The weeds, including ruderals, were represented by many species. Agrostemma githago (corn cockle) was an important contaminant of the cereal fields. Exceptional finds include a piece of charred round bread, the cereal content of a pot, and peach stone fragments. Previous information about the agriculture and food in medieval Serbia was based solely on documents that were either written after this period or that were not pertinent to the region. This study is the first direct evidence providing information about agriculture and food of the inhabitants of medieval Serbia.     

Molecular and immunological characterization of tri a 36, a low molecular weight glutenin, as a novel major wheat food allergen

Wheat is an essential element in our nutrition but one of the most important food allergen sources. Wheat allergic patients often suffer from severe gastrointestinal and systemic allergic reactions after wheat ingestion. In this study, we report the molecular and immunological characterization of a new major wheat food allergen, Tri a 36. The cDNA coding for a C-terminal fragment of Tri a 36 was isolated by screening a wheat seed cDNA expression library with serum IgE from wheat food-allergic patients. Tri a 36 is a 369-aa protein with a hydrophobic 25-aa N-terminal leader peptide. According to sequence comparison it belongs to the low m.w. glutenin subunits, which can be found in a variety of cereals. The mature allergen contains an N-terminal domain, a repetitive domain that is rich in glutamine and proline residues, and three C-terminal domains with eight cysteine residues contributing to intra- and intermolecular disulfide bonds. Recombinant Tri a 36 was expressed in Escherichia coli and purified as soluble protein. It reacted with IgE Abs of ～80% of wheat food-allergic patients, showed IgE cross-reactivity with related allergens in rye, barley, oat, spelt, and rice, and induced specific and dose-dependent basophil activation. Even after extensive in vitro gastric and duodenal digestion, Tri a 36 released distinct IgE-reactive fragments and was highly resistant against boiling. Thus, recombinant Tri a 36 is a major wheat food allergen that can be used for the molecular diagnosis of, and for the development of specific immunotherapy strategies against, wheat food allergy.     

Structural variation in the heterochromatin of rye chromosomes in triticales

Summary Although Giemsa C-banding techniques have been used extensively for assaying cereal heterochromatin, a more specific technique for analyzing cereal heterochromatin has been developed recently with the isolation of DNA sequences present in heterochromatin and their employment in in situ hybridization to cereal chromosomes. A number of triticales were examined for the occurrence of modified rye chromosomes using the in situ hybridization technique. With a heterogeneous sequence probe the amount of rye heterochromatin appears to be relatively constant in wheat backgrounds but when a specific sequence probe was employed variation was observed. Whether this variation reflects polymorphism in rye or whether it is a result of adaption of the rye genome to coexistence with the wheat genome in triticales is discussed. — The triticale Rosner was examined in detail and it was established that the rye chromosome 2R had been replaced by the wheat chromosome 2D.     

Barley Yellow Striate Mosaic Rhabdovirus Naturally Infects Cereal Crops in the Anatolian Plateau of Turkey

Field surveys of cereal crops in the Anatolian Plateau of Turkey revealed that bread wheat, durum wheat, barley, triticale and oats are naturally itifected with barley yellow striate mosaic rhabdovirus. Identification was based on symptomatology, double antibody sandwich ELISA (DAS-ELISA), tissue-blot immunoassay (TBIA) and immunoelectron microscopy (IEM). BYSMV was identified in cereal fields near Ankara, Eskisehir, Konya, Karaman and in an area 70km north east of Isparta. Virus incidence in all the fields surveyed was less than 1%. This is the first report where evidence is presented on the natural occurrence of BYSMV on cereals in Turkey.     

Isolation of lambda and YAC clones from defined regions of the rye genome

A dispersed, rye-specific element has been used to isolate clones of rye origin from wheat plants containing only a single rye chromosome arm or segment. In this way a set of 23 YAC clones has been isolated from the short arm of rye chromosome 1 (1RS). This technique was extended to isolate clones from a small region of 1RS that contains a large number of agronomically important genes. The targeted cloning method allowed the isolation of 26 classes of lambda clones representing about 5% of the region. Ten of the lambda clones could be mapped to segments within this region. A third example of the application of this technique involved the isolation of clones from a very small but fully functional rye chromosome, the midget chromosome. These clones have allowed the confirmation of the origin of the midget from 1RL, and may provide a tool for the isolation of structural elements of cereal chromosomes. This technique allows the identification of clone libraries for any rye chromosome or chromosome arm, since substitution, addition and translocation lines are available for all rye chromosomes. Furthermore, the technique allows isolation of clones derived from segments of the rye genome recombined into wheat. The method is technically simple and both lambda and YAC libraries can be constructed. Synteny between the genomes of the cereals allows region-specific libraries from rye to be used to target regions of the wheat and barley genomes.     

5-n-alkylresorcinols of whole grain cereals and whole grain cereal products as biomarkers of healthy food

Epidemiological studies suggest that consumption of whole grain cereals and whole grain cereal products have many benefical health effects, including reducing risk of diabetes, obesity, coronary heart diseases, stroke and even some cancers. Precise knowledge protective compounds present in cereal grains can be achieved only when specific biomarkers (biological marker, indicator), that could provide estimation of grain cereals absorption and intake, are established and determined. 5-n-alkylresorcinols (main fraction of phenolic compounds in cereals), because of their specific occurrence only in bran fraction, obtained in refining of milling fractions process, could be a very good candidate to play the role of biomarker of whole grain intake. They are absorbed by animals and humans, present in human plasma and as metabolites in urine. Because composition of saturated homologues of 5-n-alkylresorcinols is different in rye and wheat grains, they could be used as an indicator of the intake of the specific type of cereals and whole grain cereal products.     

THE INCIDENCE OF CERTAIN SEED-BORNE DISEASES IN COMMERCIAL SEED SAMPLES

The incidence of ergot, Claviceps purpurea (Fr.) Tul., in commercial cereal seed samples submitted to the Official Seed Testing Station from 1918 to 1957 has been examined.
Rye samples were more frequently contaminated than wheat or barley and no cereal ergots were recorded in oats.
A relatively high proportion of ergot-contaminated rye samples occurred every 8–10 years. This appeared to be associated with high relative humidity and low maximum temperature during June. Similar trends were found for wheat and barley.
No varietal differences in susceptibility to ergot contamination were found for rye or barley, but there was some evidence that spring wheat varieties were more frequently contaminated than winter ones.     

Integrating cereal genomics to support innovation in the Triticeae

The genomic resources of small grain cereals that include some of the most important crop species such as wheat, barley, and rye are attaining a level of completion that now is contributing to new structural and functional studies as well as refining molecular marker development and mapping strategies for increasing the efficiency of breeding processes. The integration of new efforts to obtain reference sequences in bread wheat and barley, in particular, is accelerating the acquisition and interpretation of genome-level analyses in both of these major crops.