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1.
Blatter RH Jacomet S Schlumbaum A 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,104(2-3):329-337
A partial promoter region of the high-molecular weight (HMW) glutenin genes was studied in two wheat specimens, a 300 year-old
spelt (Triticum spelta L.) and an approximately 250 year-old bread wheat (Triticum aestivum L.) from Switzerland. Sequences were compared to a recent Swiss landrace T. spelta ’Oberkulmer.’ The alleles from the historical bread wheat were most similar to those of modern T. aestivum cultivars, whereas in the historical and the recent spelt specific alleles were detected. Pairwise genetic distances up to
0.03 within 200 bp from the HMW Glu-A1-2, Glu-B1-1 and Glu-B1-2 alleles in spelt to the most-similar alleles from bread wheat
suggest a polyphyletic origin. The spelt Glu-B1-1 allele, which was unlike the corresponding alleles in bread wheat, was closer
related to an allele found in tetraploid wheat cultivars. The results are discussed in context of the origin of European spelt.
Received: 22 July 2000 / Accepted: 27 April 2001 相似文献
2.
Yan Y Hsam SL Yu JZ Jiang Y Ohtsuka I Zeller FJ 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(7):1321-1330
The allelic compositions of high- and low-molecular-weight subunits of glutenins (HMW-GS and LMW-GS) among European spelt (Triticum spelta L.) and related hexaploid and tetraploid Triticum species were investigated by one- and two-dimensional polyacrylamide-gel electrophoresis (PAGE) and capillary electrophoresis (CE). A total of seven novel glutenin alleles (designated A1a*, B1d*, B1g*, B1f*, B1j*, D1a* at Glu-1 and A3h at the Glu-3 loci, respectively) in European spelt wheat were detected by SDS-PAGE, which were confirmed further by employing A-PAGE and CE methods. Particularly, two HMW-GS alleles, Glu-B1d* coding the subunits 6.1 and 22.1, and Glu-B1f* coding the subunits 13 and 22*, were found to occur in European spelt with frequencies of 32.34% and 5.11%, respectively. These two alleles were present in cultivated emmer (Triticum dicoccum), but they were not observed in bread wheat (Triticum aestivum L.). The allele Glu-B1g* coding for 13* and 19* subunits found in spelt wheat was also detected in club wheat (Triticum compactum L.). Additionally, two alleles coding for LMW-GS, Glu-A3h and Glu-B3d, occurred with high frequencies in spelt, club and cultivated emmer wheat, whereas these were not found or present with very low frequencies in bread wheat. Our results strongly support the secondary origin hypothesis, namely European spelt wheat originated from hybridization between cultivated emmer and club wheat. This is also confirmed experimentally by the artificial synthesis of spelt through crossing between old European emmer wheat, T. dicoccum and club wheat, T. compactum.Communicated by H.F. Linskens 相似文献
3.
N. A. Kozub R. L. Boguslavskii I. A. Sozinov Ye. V. Tverdokhleb I. N. Xynias Ya. B. Blume A. A. Sozinov 《Cytology and Genetics》2014,48(1):33-41
The diversity at eight storage protein loci was analyzed in the collection of Triticum spelta accesssions from the National Center for Plant Genetic Resources of Ukraine (most of accessions were European spelts). Seven alleles at the Gli-B1 locus; five alleles at the Gli-A1 and Glu-B1 loci; three alleles at the Glu-B1 locus; and two alleles at the Gli-D1, Gli-B5, Glu-A1, and Glu-D1 loci were identified. Most alleles are found among common wheat cultivars; only five spelt-specific alleles were detected. The high frequency of the GliB1hs* and h alleles encoding the 45-type γ-gliadin among European spelt and durum wheat, as well as the occurrence of these alleles in T. dicoccum (particularly, in emmer accessions from Switzerland and Germany), are evidence in favor of von Büren’s hypothesis that the European spelt arose from the hybridization between tetraploid wheat with the 45-type γ-gliadin and hexaploid wheat. The analysis of genetic distances based on the genotypes at eight storage protein loci allowed differentiating the Asian spelt accession from European spelts. 相似文献
4.
O. S. Dedkova E. D. Badaeva O. P. Mitrofanova A. V. Zelenin V. A. Pukhalskiy 《Russian Journal of Genetics》2004,40(10):1111-1126
Intraspecific divergence of hexaploid wheat Triticum spelta was studied by C-banding method in 41 accessions of different geographic origins. The spelt accessions did not differ in karyotype structure or heterochromatin distribution from common wheat, but showed greater intraspecific polymorphism by chromosome rearrangements (translocations, inversions) and banding patterns. On evidence of C-banding patterns, spelt was assumed to occupy an intermediate position between tetraploid and hexaploid wheat species. Accessions of the Asian spelt subspecies had more diverse banding patterns than European accessions. A relatively high frequency of chromosome rearrangements was observed in Iranian accessions. Visual analysis revealed high uniformity of chromosome banding patterns in T. spelta populations of Afghanistan, Spain, and Germany (Bavarian group), suggesting a significant role of the founder effect in their evolution. 相似文献
5.
L. Caballero L. M. Martin J. B. Alvarez 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(1):124-128
Spelt wheat (Triticum aestivum ssp. spelta L. em. Thell.) is a hulled wheat of Germanic origin that survives at marginal areas in Asturias (Spain). The HMW glutenin
subunit composition of 403 accessions of spelt wheat from Spain has been analysed by SDS-PAGE. Three allelic variants were
detected for Glu-A1. For the Glu-B1 locus, two of seven alleles detected have not been found before; while four of nine alleles detected for the Glu-D1 are not previously described. Considering the three loci, twenty five combinations were found among all the evaluated lines.
This wide polymorphism could be used to transfer new quality genes to wheat, and widen the genetic basis of them.
Received: 19 September 2000 / Accepted: 20 October 2000 相似文献
6.
Sewa Ram 《Journal of plant biochemistry and biotechnology.》2003,12(2):151-155
One hundred and seventy two wheat varieties including twenty-five durum wheat cultivars were evaluated for high molecular weight glutenin subunit (HMW-GS) composition using SDS-PAGE. The relationship between HMW-GS and sedimentation tests for dough strength was studied. Three alleles were present at the Glu-A1 locus, eight at Glu-B1 and two at Glu-D1 in bread wheat. The data indicated the prevalence of the Glu-A1b allele (63.5%) at the Glu-A1 and Glu-D1a (71.4%) at Glu-D1 loci. Three alleles, namely Glu-B1b (30.61%), Glu-B1c (25.85%) and Glu-B1i (34.00%) represented about 90% of the alleles at Glu-B1 locus. The combination of Glu-A1b, Glu-B1i and Glu-D1d alleles exhibited highest dough strength as measured by sedimentation value in comparison to other combinations (p<0.001). However, this combination was present only in 7% of the samples evaluated. In durum wheat, the null allele (Glu-A1c) was observed more frequently (76%) than the Glu-A1b allele (24%). Glu-B1f and Glu-B1e alleles represented equally (32% each). Protein subunits 13+16 and 6+8 were found correlated positively (p<0.05) with improved dough strength as compared to subunit 20 in durum wheat. This information can be a valuable reference for designing breeding programme for the improvement of bread and pasta making quality of bread and durum wheats, respectively in India. 相似文献
7.
Ali Izadi-Darbandi Bahman Yazdi-Samadi Ali-Akbar Shanejat-Boushehri Mohsen Mohammadi 《Journal of genetics》2010,89(2):193-199
Proline and glutamine-rich wheat seed endosperm proteins are collectively referred to as prolamins. They are comprised of
HMW-GSs, LMW-GSs and gliadins. HMW-GSs are major determinants of gluten elasticity and LMW-GSs considerably affect dough extensibility
and maximum dough resistance. The inheritance of glutenin subunits follows Mendelian genetics with multiple alleles in each
locus. Identification of the banding patterns of glutenin subunits could be used as an estimate for screening high quality
wheat germplasm. Here, by means of a two-step 1D-SDS-PAGE procedure, we identified the allelic variations in high and low-molecular-weight
glutenin subunits in 65 hexaploid wheat (Triticum aestivum L.) cultivars representing a historical trend in the cultivars introduced or released in Iran from the years 1940 to 1990.
Distinct alleles 17 and 19 were detected for Glu-1 and Glu-3 loci, respectively. The allelic frequencies at the Glu-1 loci demonstrated unimodal distributions. At Glu-A1, Glu-B1 and Glu-D1, we found that the most frequent alleles were the null, 7 + 8, 2 + 12 alleles, respectively, in Iranian wheat cultivars.
In contrast, Glu-3 loci showed bimodal or trimodal distributions. At Glu-A3, themost frequent alleles were c and e. At Glu-B3 the most frequent alleles were a, b and c. At Glu-D3 locus, the alleles b and a, were the most and the second most frequent alleles in Iranian wheat cultivars. This led to a
significantly higher Nei coefficient of genetic variations in Glu-3 loci (0.756) as compared to Glu-1 loci (0.547). At Glu-3 loci, we observed relatively high quality alleles in Glu-A3 and Glu-D3 loci and low quality alleles at Glu-B3 locus. 相似文献
8.
A. A. Levy M. Feldman 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1988,75(4):651-658
Summary Polymorphism of high molecular weight (HMW) glutenin subunits in 466 accessions of the wild tetraploid wheat Triticum turgidum var. dicoccoides in Israel was characterized with regard to the ecogeographical distribution of the HMW glutenin alleles, both between and within 22 populations, and along transects in a single population. While some populations were monomorphic for all the HMW glutenin loci, namely, Glu-A1-1, Glu-A1-2, Glu-B1-1 and Glu-B1-2, others contained up to four alleles per locus. Intrapopulation variability could be predicted by the geographical distribution: marginal populations tended to be more uniform than those at the center of distribution. The various HMW glutenin alleles tended to be clustered, both at a regional level and within a single population along transects of collection. It is suggested that this clustering is due to selection pressures acting both at a regional and at a microenvironmental level. This was confirmed by the significant correlations found between the MW of subunits encoded by Glu-A1-1 and the populations' altitude, average temperature and rainfall. The possible selective values of seed storage proteins are discussed. 相似文献
9.
Intraspecific divergence of hexaploid wheat Triticum spelta was studied by chromosome C-banding in 41 accessions of different geographic origins. The spelt accessions did not differ in karyotype structure or heterochromatin distribution from common wheat, but showed greater intraspecific polymorphism for chromosome rearrangements (translocations, inversions) and banding patterns. On evidence of C-banding patterns, spelt was assumed to occupy an intermediate position between tetraploid and hexaploid wheat species. Accessions of the Asian spelt subspecies had more diverse banding patterns than European accessions. A relatively high frequency of chromosome rearrangements was observed in Iranian accessions. Visual analysis revealed high uniformity of chromosome banding patterns in T. spelta populations of Afghanistan, Spain, and Germany (Bavarian group), suggesting a significant role of the founder effect in their evolution. 相似文献
10.
The allelic diversity of high-moleculat-weght glutenin subunits (HMWGS) in Russian and Ukrainian bread wheat cultivars was
analyzed. The diversity of spring wheat cultivars for alleles of the Glu-1 loci is characterized by medium values of the polymorphism polymorphism information content (PIC), and in winter wheats it varies from high at the Glu-A1 locus to low at the Glu-D1 locus. The spring and winter cultivars differ significantly in the frequencies of alleles of the glutenin loci. The combination
of the Glu-A1b, Glu-B1c, and Glu-D1a alleles prevails among the spring cultivars, and the combination of the Glu-A1a, Glu-B1c, and Glu-D1d alleles prevails among the winter cultivars. The distribution of the Glu-1 alleles significantly depends on the moisture and heat supply in the region of origin of the cultivars. Drought resistance
is associated with the Glu-D1a allele in the spring wheat and with the Glu-B1b allele in the winter wheat. The sources of the Glu-1 alleles were identified in the spring and wheat cultivars. The analysis of independence of the distribution of the spring
and winter cultivars by the market classes and by the alleles of the HMWGS loci showed a highly significant association of
the alleles of three Glu-1 loci with the market classes in foreign cultivars and independence or a weak association in the Russian and Ukrainian cultivars.
This seems to be due to the absence of a statistically substantiated system of classification of the domestic cultivars on
the basis of their quality. 相似文献
11.
O. I. Zaitseva A. A. Burakova A. T. Babkenov S. A. Babkenova M. U. Utebayev V. A. Lemesh 《Cytology and Genetics》2017,51(6):432-440
The composition and quantity of high-molecular-weight glutenin subunits plays an important role in determining the bread-making quality of wheat. Molecular-genetic analysis of allelic composition of high-molecular-weight glutenin genes in 102 bread wheat cultivars and lines from different geographical regions was conducted. Three alleles at the Glu-A1 locus, nine alleles at the Glu-B1 locus, and two alleles at the Glu-D1 locus were identified. Among the investigated cultivars and lines, 21 were characterized by intracultivar polymorphism. High allelic variation of high-molecular-weight glutenin subunit genes was shown for the collection: 21 and 9 combinations were defined in monomorphic and polymorphic cultivars and lines, respectively. However, the major part of the collection (66.7%) contained four allelic combinations: Glu-A1b Glu-B1c Glu-D1d, Glu-A1b Glu-B1c Glu-D1-2a, Glu-A1a Glu-B1c Glu-D1d, and Glu-A1b Glu-B1c Glu-D1d/Glu-D1-2a. Fourteen cultivars of bread wheat were selected, and they were characterized by a favorable allelic composition of Glu-1 loci. 相似文献
12.
The origin of spelt and free-threshing hexaploid wheat 总被引:1,自引:0,他引:1
Dvorak J Deal KR Luo MC You FM von Borstel K Dehghani H 《The Journal of heredity》2012,103(3):426-441
It is widely believed that hexaploid wheat originated via hybridization of hulled tetraploid emmer with Aegilops tauschii (genomes DD) and that the nascent hexaploid was spelt, from which free-threshing wheat evolved by mutations. To reassess the role of spelt in the evolution of Triticum aestivum, 4 disomic substitution lines of Ae. tauschii chromosome 2D in Chinese Spring wheat were developed and one of them was used to map the Tg locus, which controls glume tenacity in Ae. tauschii, relative to simple sequence repeat (SSR) and expressed sequence tag loci on wheat chromosome 2D. The segregation of SSR markers was used to assess the presence of Tg alleles in 11 accessions of spelt, both from Europe and from Asia. Ten of them had an inactive tg allele in the D genome and most had an active Tg allele in the B genome. This is consistent with spelt being derived from free-threshing hexaploid wheat by hybridization of free-threshing wheat with hulled emmer. It is proposed that the tetraploid parent of hexaploid wheat was not hulled emmer but a free-threshing form of tetraploid wheat. 相似文献
13.
Wheat storage proteins: diversity of HMW glutenin subunits in wild emmer from Israel 总被引:2,自引:0,他引:2
E. Nevo P. I. Payne 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,74(6):827-836
Summary The diversity of HMW glutenin subunits in the tetraploid wild progenitor of wheat, Triticum turgidum var. dicoccoides was studied electrophoretically in 231 individuals representing 11 populations of wild emmer from Israel. The results show that (a) The two HMW glutenin loci, Glu-A1 and Glu-B1, are rich in variation, having 11 and 15 alleles, respectively, (b) Genetic variation in HMW glutenin subunits is often severely restricted in individual populations, supporting an island population genetic model, (c) Significant correlations were found between glutenin diversity and the frequencies of specific glutenin alleles and physical (climate and soil) and biotic (vegetation) variables. Our results suggest that: (a) at least part of the glutenin polymorphisms in wild emmer can be accounted for by environmental factors and (b) the endosperm of wild emmer contains many allelic variants of glutenin storage proteins that are not present in bread wheat and could be utilized in breeding varieties with improved bread-making qualities. 相似文献
14.
M. Ciaffi D. Lafiandra E. Porceddu S. Benedettelli 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(4):474-480
Seed storage-protein variation at theGlu-A1,Glu-B1 andGli-B1/Glu-B3 loci in the tetraploid wild progenitor of wheat,T. dicoccoides, was studied electrophoretically in 315 individuals representing nine populations from Jordan and three from Turkey. A total of 44 different HMW-glutenin patterns were identified, resulting from the combination of 15 alleles in the A genome and 19 in the B genome. Twenty-seven new allelic variants, 12 at theGlu-A1 locus and 15 at theGlu-B1 locus, were identified by comparing the mobilities of their subunits to those previously found in bread and durum wheats. The novel variants include six alleles at theGlu-A1 locus showing both x and y subunits. The genes coding for the 1Bx and 1By subunits showed no or very little (3%) inactivity, the 1Ax gene showed a moderate degree (6.3%) of inactivity whereas the gene coding for lAy showed the highest degree of inactivity (84.8%). A high level of polymorphism was also present for the omega- and gamma-gliadins and LMW-glutenin subunits encoded by genes at the linkedGli-B1 andGlu-B3 loci (19 alleles). Some Jordanian accessions were found to contain omega-gliadin 35, gamma-gliadin 45, and LMW-2 also present in cultivated durum wheats and related to good gluten viscoelasticity. The newly-discovered alleles enhance the genetic variability available for improving the technological quality of wheats. Additionally some of them may facilitate basic research on the relationship between industrial properties and the number and functionality of HMW- and LMW-glutenin subunits. 相似文献
15.
Raman H Ryan PR Raman R Stodart BJ Zhang K Martin P Wood R Sasaki T Yamamoto Y Mackay M Hebb DM Delhaize E 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(3):343-354
Allele diversities of four markers specific to intron three, exon four and promoter regions of the aluminum (Al) resistance
gene of wheat (Triticum aestivum L.) TaALMT1 were compared in 179 common wheat cultivars used in international wheat breeding programs. In wheat cultivars released during
the last 93 years, six different promoter types were identified on the basis of allele size. A previous study showed that
Al resistance was not associated with a particular coding allele for TaALMT1 but was correlated with blocks of repeated sequence upstream of the coding sequence. We verified the linkage between these
promoter alleles and Al resistance in three doubled haploid and one intercross populations segregating for Al resistance.
Molecular and pedigree analysis suggest that Al resistance in modern wheat germplasm is derived from several independent sources.
Analysis of a population of 278 landraces and subspecies of wheat showed that most of the promoter alleles associated with
Al resistance pre-existed in Europe, the Middle East and Asia prior to dispersal of cultivated germplasm around the world.
Furthermore, several new promoter alleles were identified among the landraces surveyed. The TaALMT1 promoter alleles found within the spelt wheats were consistent with the hypothesis that these spelts arose on several independent
occasions from hybridisations between non-free-threshing tetraploid wheats and Al-resistant hexaploid bread wheats. The strong
correlation between Al resistance and Al-stimulated malate efflux from the root apices of 49 diverse wheat genotypes examined
was consistent with the previous finding that Al resistance in wheat is conditioned primarily by malate efflux. These results
demonstrate that the markers based on intron, exon and promoter regions of TaALMT1 can trace the inheritance of the Al resistance locus within wheat pedigrees and track Al resistance in breeding programmes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
16.
P. Bertin D. Grégoire S. Massart D. de Froidmont 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(1):148-156
Spelt and common wheat constitute two of the six groups of the hexaploid wheats with an AABBDD genome. Spelt culture has been
progressively replaced by that of common wheat which out-yields spelt under high-input conditions. In the last decades, spelt
breeders intended to introduce the yield-potential and bread-making qualities of common wheat into spelt, by frequent crossings
between accessions of these two different groups. The present study aims at determining the genetic basis of modern spelt
cultivars in terms of intra-group variability and inter-group (spelt vs common wheat) distances, by using microsatellite markers
developed for common wheat. The allelic composition of 30 spelt and nine common wheat accessions was determined at 17 microsatellite
loci. The coefficient of co-ancestry (ƒ) and the genetic distances (1 - proportion of shared alleles) based upon allelic composition
were calculated for all pairs of accessions. Two dendrograms were constructed using the UPGMA method. Amplification products
were found for all loci on most accessions. A total of 113 alleles was identified, of which 60.2% were specific to spelt or
common wheat. The correlation between (1 –ƒ ) and the genetic distance was high (0.701***). The mean pairwise genetic distance
was 0.656 ± 0.181 over the 39 accessions, 0.706 ± 0.14 among common wheat and 0.573 ± 0.172 among spelt. The mean genetic
distance between spelt and wheat was 0.782 ± 0.113. The two dendrograms were in accordance with each other and clearly separated
the spelt from the common wheat accessions. It is concluded that microsatellites developed for common wheat and distances
based on the proportion of shared alleles are powerful tools for reconstructing phylogenies in spelt, and that the genetic
basis of modern spelt cultivars is narrow despite frequent crosses made with bread wheat.
Received: 26 January 2000 / Accepted: 26 May 2000 相似文献
17.
Li W Wan Y Liu Z Liu K Liu X Li B Li Z Zhang X Dong Y Wang D 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(5):1093-1104
1Bx14 is a member of the high molecular weight (HMW) glutenin subunits specified by wheat Glu-B1-1 alleles. In this work, we found that the full-length amino acid sequence of 1Bx14 derived from cloned coding region was similar, but not identical, to that of 1Bx20. In the N-terminal domains of 1Bx14 and 1Bx20, the last two of the three cysteine residues, which are conserved in 1Bx7, 1Bx17 and homoeologous 1Ax and 1Dx subunits, were replaced by tyrosine residues. In the 5 flanking regions (–900 to –1,200 bp relative to the start codon), a novel miniature inverted-repeat transposable element insertion was present in 1Bx14 and 1Bx20 but not 1Bx7 and 1Bx17. 1Bx14 and 1Bx20 like alleles were readily found in tetraploid wheat subspecies but not several S genome containing Aegilops species. Phylogenetic analysis showed that the four molecularly characterized Glu-B1-1 alleles (1Bx7, 1Bx14, 1Bx17, 1Bx20) could be divided into two allelic lineages. The lineage represented by 1Bx7 and 1Bx17 was more ancient than the one represented by 1Bx14 and 1Bx20. Combined, our data establish that 1Bx14 and 1Bx20 represent a novel subclass of Glu-B1-1 alleles. Based on current knowledge, potential mechanism involved in the differentiation of two Glu-B1-1 lineages is discussed.Electronic Supplementary Material Supplementary material is available for this article at 相似文献
18.
The allelic diversity of high-moleculat-weght glutenin subunits (H WIGS) in Russian and Ukrainian bread wheat cultivars was analyzed. The diversity of spring wheat cultivars for alleles of the Glu-1 loci is characterized by medium values of the polymorphism index (polymorphism information content, PlC), and in winter wheats it varies from high at the Glu-A1 locus to low at the Glu-D1 locus. The spring and winter cultivars differ significantly in the frequencies of alleles of the glutenin loci. The combination of the Glu-A1b, Glu-B1c, and Glu-D1a alleles prevails among the spring cultivars, and the combination of the Glu-A1a, Glu-B1c, and Glu-D1d alleles prevails among the winter cultivars. The distribution of the Glu-1 alleles significantly depends on the moisture and heat supply in the region of origin of the cultivars. Drought resistance is associated with the Glu-D1a allele in the spring wheat and with the Glu-B1b allele in the winter wheat. The sources of the Glu-1 alleles were identified in the spring and wheat cultivars. The analysis of independence of the distribution of the spring and winter cultivars by the market classes and by the alleles of the HMWGS loci showed a highly significant association of the alleles of three Glu-1 loci with the market classes in foreign cultivars and independence or a weak association in the Russian and Ukrainian cultivars. This seems to be due to the absence of a statistically substantiated system of classification of the domestic cultivars on the basis of their quality. 相似文献
19.
Zhenxian Gao Guoying Tian Yanxia Wang Yaqing Li Qiao Cao Meikun Han Zhanliang Shi 《Journal of genetics》2018,97(4):905-910
In common wheat (Triticum aestivum L.), allelic variations of Glu-1 loci have important influences on grain end-use quality. The allelic variations in high molecular weight glutenin subunits (HMW-GSs) were identified in 151 hexaploid wheat varieties representing a historical trend in the cultivars introduced or released in Hebei province of China from the years 1970s to 2010s. Thirteen distinct alleles were detected for Glu-1. At Glu-A1, Glu-B1 and Glu-D1, we found that the most frequent alleles were the 1 (43.0%), 7+8 (64.9%), 2+12 (74.8%) alleles, respectively, in wheat varieties. Twenty two different HMW-GS compositions were observed in wheat. Twenty-five (16.6%) genotypes possessed the combination of subunits 1, 7+8, 2+12, 25 (16.6%) genotypes had subunit composition of 2*, 7+8, 2+12; 20 (13.2%) genotypes had subunit composition of null, 7+8, 2+12. The frequency of other subunit composition was less than 10%. The Glu-1 quality score greater than or equal to 9 accounted for 20.6% of the wheat varieties. The percentage of superior subunits (1 or 2* subunit at Glu-A1 locus; 7+8, 14+15 or 17+18 at Glu-B1 locus; 5+10 or 5+12 at Glu-D1 locus) was an upward trend over the last 40 years. The more different superior alleles correlated with good bread-making quality should be introduced for their usage in wheat improvement efforts. 相似文献
20.
Two major genes for Na(+) exclusion in durum wheat, Nax1 and Nax2, that were previously identified as the Na(+) transporters TmHKT1;4-A2 and TmHKT1;5-A, were transferred into bread wheat in order to increase its capacity to restrict the accumulation of Na(+) in leaves. The genes were crossed from tetraploid durum wheat (Triticum turgidum ssp. durum) into hexaploid bread wheat (Triticum aestivum) by interspecific crossing and marker-assisted selection for hexaploid plants containing one or both genes. Nax1 decreased the leaf blade Na(+) concentration by 50%, Nax2 decreased it by 30%, and both genes together decreased it by 60%. The signature phenotype of Nax1, the retention of Na(+) in leaf sheaths resulting in a high Na(+) sheath:blade ratio, was found in the Nax1 lines. This conferred an extra advantage under a combination of waterlogged and saline conditions. The effect of Nax2 on lowering the Na(+) concentration in bread wheat was surprising as this gene is very similar to the TaHKT1;5-D Na(+) transporter already present in bread wheat, putatively at the Kna1 locus. The results indicate that both Nax genes have the potential to improve the salt tolerance of bread wheat. 相似文献