首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 93 毫秒
1.
Waxy proteins in diploid, tetraploid and hexaploid wheats   总被引：4，自引：0，他引：4  
Electrophoretic analyses of waxy proteins, encoded by genes present at the Wx‐1 loci, present in several cultivars and accessions of hexaploid wheat, Triticum aestivum, have permitted the detection of null alleles at the Wx‐B1 and Wx‐D1 loci. Polymorphism at the Wx‐A1 and Wx‐B1 loci was also investigated in several accessions of tetraploid wheats, Triticum durum, Triticum dicoccoides and Triticum timopheevi, and in diploid species, Triticum urartu, Triticum boeoticum and Triticum monococcum. One null allele at the Wx‐A1 locus and three polymorphic alleles at Wx‐B1 locus were detected in T. durum; a new allele at one of the two waxy loci was identified in the tetraploid wheat T. timopheevi; no polymorphism was detected in diploid species. Polymerase chain reaction techniques made possible the detection of further polymorphism existing at the Wx‐1 loci and the reason for the lack of expression of the null genotypes to be investigated. The null forms detected at each locus have been used to produce complete sets of partial and total waxy lines in durum and bread wheat.  相似文献   

2.
A collection of 89 accessions of diploid species of wheat was analysed for waxy protein in the grain: 39 accessions of Einkorn wheats, 41 accessions of Sitopsis section wheat and nine accessions of Triticum tauschii. The electrophoretic patterns showed low polymorphism. In each group of wheat, a single and different allele was detected. In accessions of Einkorn wheats that allele had a similar electrophoretical mobility to the Wx‐A1a allele of the bread wheat ‘Chinese Spring’, in accessions of the Sitopsis section it had a similar mobility to that of the Wx‐B1f allele of tetraploid wheat, and in the accessions of T. tauschii, it was similar to the Wx‐D1a allele of the bread wheat ‘Chinese Spring’. The accessions were also analysed for apparent amylose content. Results showed that amylose content ranged from 22 to 35% in Einkorn wheats, from 28 to 41% in the Sitopsis section and from 26 to 35% in accessions of T. tauschii.  相似文献   

3.
Polymorphism of waxy proteins in Iberian hexaploid wheats   总被引：4，自引：0，他引：4  
A collection of 130 cultivars of bread wheat, 332 landraces of bread wheat and 144 spelt wheats was analysed for waxy proteins in the grain. The electrophoretic patterns showed very low polymorphism and most of the hexaploid wheats had the Wx-Ala, Wx-D1a and Wx-B1 alleles of ‘Chinese Spring’. Two alleles were detected at Wx-A1 (Wx-A1a, and Wx-A1b (null)), the latter was present in only 5.1% of the bread wheat landraces and 7.6% ofthe spelt wheats. No allelic variation was found at the Wx-D1 locus and all the hexaploid wheats had the Wx-D1a allele. Wx-B1 was the most polymorphic locus, with three alleles detected: Wx-B1a, Wx-B1b (null) and Wx-Blc coding for a Wx-B1 protein with a slightly different mobility from Wx-B1a. The null Wx-B1b allele was found in 10.8% of the bread wheat cultivars, 21.4% of the bread wheat landraces and 12.5% of the spelt wheats. Among the 604 hexaploid wheats analysed, only two bread wheat landraces (0.6%) and two spelt wheats (1.4%) had the null allele at both Wx-A1 and Wx-B1 loci.  相似文献   

4.
To assist waxy wheat breeding a DNA marker was developed to discriminate mutant and normal alleles at the Wx‐D1 locus. This polymerase chain reaction‐based marker distinguishes the mutant from the normal allele by targeting the previously reported deletion basis of the mutant. The marker codominantly identifies the normal allele of the Wx‐D1 gene from the mutant allele originated from the Chinese landrace ‘Baihoumai’. However, attempts with a number of primer combinations targeting this deletion failed to amplify the corresponding fragment from an unrelated wheat line (NP150) that has a mutant null allele at the same locus. This indicates that NP150 has a different mutant allele from that of ‘Baihoumai’. This marker is a useful tool to identify wheat cultivars with mutant and normal alleles of the Wx‐D1 gene, and is used in marker‐assisted selection of the Wx‐D1 gene in our waxy wheat breeding programme.  相似文献   

5.
M. Yamamori 《Euphytica》2009,165(3):607-614
In common and durum wheats (Triticum aestivum L. and T. durum Desf.), variant waxy (Wx) alleles have been reported for three Wx proteins (Wx-A1, -B1 and -D1), responsible for amylose synthesis in flour starch. Five variant alleles, Wx-A1c, -A1e, -B1c, -B1d and -D1c, were examined to elucidate their effects on amylose content in flour starch. Common wheat lines carrying a Wx protein produced by one variant (e.g., Wx-A1c) and one control (e.g., Wx-A1a) allele were bred and their starches were compared. Results showed that Wx-A1e did not produce amylose (waxy phenotype), whereas three alleles (Wx-A1c, -B1c and -B1d) reduced amylose, and -D1c might have increased it slightly. Most data on blue value, swelling power and starch paste clarity in water and dimethyl sulphoxide also suggested the variant Wx alleles either reduced or increased amylose content.  相似文献   

6.
为明确不同Wx基因对小麦直链淀粉含量的影响以及筛选面条品质优异的基因型,以糯小麦品系Caiwx (aabbdd)为3个Wx基因隐性突变供体亲本,以扬麦01-2 (AABBDD)为轮回亲本,利用连续回交结合花粉碘染、STS标记和同工酶标记检测方法,创制了8种Wx基因纯合基因型的近等基因系,其基因型分别为AABBDD、AABBdd、AAbbDD、AAbbdd、aaBBDD、aaBBdd、aabbDD和aabbdd。利用这些基因型探讨了不同Wx基因对直链淀粉含量及面条感官品质的影响。结果表明,各系的直链淀粉含量为0.9%~24.8%,系间差异显著;糯小麦型(aabbdd)直链淀粉含量最低,双缺失型和单缺失型其次,双缺失型中aaBBdd型含量最高,单缺失型中AAbbDD型含量最低,表明Wx-B1对直链淀粉的合成作用最大。糯小麦型面条的色泽、表观、软硬度、黏性、韧性得分以及总分显著低于其他类型及轮回亲本扬麦01-2;单缺失型面条的色泽、表观得分、总分显著高于轮回亲本扬麦01-2,其中aaBBDD型面条品质表现突出,与市售优质面条粉“雪花粉”制作的面条得分相当,而其他7种基因型及轮回亲本扬麦01-2的面条评分均显著低于雪花粉。说明可以通过遗传操作Wx基因培育优质面条小麦品种。  相似文献   

7.
Granule‐bound starch synthase of ancient wheat and related species was examined by sodium dodecyl sulphate polyacrylamide gel. A total of 13 different alleles were revealed in a collection of three accessions of diploid wheat, six accessions of tetraploid wheat, 49 accessions of spelt wheat, nine accessions of Sitopsis and two accessions of Aegilops tauschii. A new allele named Wx‐A1a′ appeared in four spelt wheat accessions. The tetraploid wheat accessions evaluated did not show any polymorphism; nevertheless the tetraploid accessions of Sitopsis section revealed three novel alleles. The novel allele Wx‐Ddn1g was found in two accessions of A. ventricosa and the Wx‐Ddcm1h and Wx‐Ddcm1i in two accessions of A. crassa. A novel allele named Wx‐Au1g was found in Triticum urartu, which is different from the also new Wx‐Am1h allele of T. monococcum. The diploid‐related species accessions revealed two novel alleles named Wx‐Bsl1h and Wx‐Bs1g found, respectively, in A. longissima and A. speltoides. The amylose content was measured for the different alleles found in all evaluated species and no significant effects of the allele composition on the amylose content were detected.  相似文献   

8.
Waxy (Wx) protein is a key enzyme for synthesis of amylose in endosperm. Amylose content in wheat grain influences the quality of end‐use products. Seven alleles have been described at the Wx‐D1 locus, but only two of them (Wx‐D1b, Wx‐D1e) were genotyped with codominant markers. The waxy wheat line K107Wx1 developed by treating ‘Kanto 107’ seeds with ethyl methanesulphonate carries the Wx‐D1d allele. However, no molecular basis supports this nomenclature. In the present study, DNA sequence analysis confirmed that a single nucleotide polymorphism in the sixth exon of Wx‐D1 changed tryptophan at position 301 into a termination codon. Based on this sequence variation, a PCR‐based KASP marker was developed to detect this point mutation using 68 BC8F1 plants and 297 BC8F2 lines derived from the cross ‘Ningmai 14’*9/K107Wx1. Combined with codominant markers for the Wx‐A1 and Wx‐B1 alleles, waxy and non‐waxy near‐isogenic lines were distinguished. The KASP marker was efficient in identifying the mutant allele and can be used to transfer waxiness to elite lines.  相似文献   

9.
The composition of 324 European wheat cultivars were analysed at the three granule‐bound starch synthase (GBSS I) loci. Protein separation was first made by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis (SDS‐PAGE. A specific two‐dimensional (2D) electrophoresis (immobilized pH gradient × SDS‐PAGE) using an Immobiline dry strip in the first dimension was developed to resolve the GBSS I proteins more clearly and to confirm some results. Very low polymorphism was found. Among the 324 cultivars analysed, only one carried a Wx‐A1 null allele (Wx‐A1b) and none was found to have the Wx‐2D null allele. As described in the literature the Wx‐B1 locus was more polymorphic and the null allele was encountered in 11 cultivars. The use of 2D electrophoresis allowed us to find another type of variant which presented as having thicker band with same mobility as the Wx‐D1 protein in SDS‐PAGE. Twelve per cent of the cultivars analysed presented this band and could have been previously mistaken for cultivars carrying the Wx‐B1 null allele. Indeed this band probably corresponded to the Wx‐B1? or Wx‐B1e allele overlapping with the Wx‐D1a allele in SDS‐PAGE.  相似文献   

10.
Greater variability in starch properties is found in lower ploidy wheats than in commercial hexaploid wheats. This paper reports on the starch properties and variability in granule bound starch synthase (GBSS) loci of 17 diploid (Aegilops tauschii) and 12 tetraploid (durums) potential progenitors of wheat, compared with 29 synthetic hexaploid wheats produced from such progenitors. Starch properties examined were granule size distribution, swelling power, amylose content, gelatinisation and amylose-lipid dissociation properties. A PCR screening method was able to detect the presence or absence of each of the three GBSS genes. It also detected polymorphisms in eight diploids and nine hexaploids, all displaying the same 25 bases deletion in the D genome allele of GBSS. Two tetraploids and five hexaploids were null 4A for GBSS. There was little difference in the amylose contents and amylose-lipid dissociation peak temperatures of the synthetic hexaploids and the lower ploidy wheats. The synthetic hexaploids showed intermediate swelling power values with the durums giving the highest swelling powers. The durums also had higher B granule contents than the A. tauschii accessions, but not as high as the synthetics. However, the A. tauschii samples gave the highest gelatinisation peak temperatures. The presence of the null 4A mutation was positively correlated with swelling power, amylose content and DSC measurements. The new smaller D genome allele of GBSS was associated with slightly higher swelling power. These results confirm the value of wheat progenitor lines as sources of new starch properties for hexaploid wheat. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

11.
Gel-electrophoretic analyses detected polymorphism of two waxy (Wx) proteins, Wx-Al and Wx-Bl, in 334 accessions of the emmer group of tetraploid wheat, Triticum dicoccoides, T. dicoccum and T. durum. The null allele for the Wx-Al protein (Wx-Alb) was found in one accession of T. dicoccoides and seven of T. dicoccum, but it was not present in those T. durum accessions analysed. The null allele for the Wx-Bl protein (Wx-Blb) did not occur in three emmer-wheat species. Wx-Al and Wx-Bl proteins showing alteration in mobility in SDS-PAGE gel or in isoelectric points were found in five accessions and considered to be the products of new alleles, Wx-Ald, Wx-Ale and/or Wx-Bld. Densitometric analysis of Wx protein bands revealed that Wx-Al was present in smaller amounts than Wx-B1 in almost all accessions.  相似文献   

12.
T. Nakamura    M. Yamamori    H. Hirano  S. Hidaka 《Plant Breeding》1993,111(2):99-105
Two cultivars with a low amylose content, Kanto107 (K107) and K79, were discovered in Japanese common wheat (Triticum aestivum L.). The amount of Wx protein, identified as a single major starch granule-bound protein of about 61 kD by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), was greatly decreased in those two cultivars. Analysis of their Wx protein with a modified SDS-PAGE and two dimensional-PAGE showed that two of the three Wx proteins, produced by Wx-A1 and Wx-B1 loci, were not detected. It was thus concluded that only one locus, Wx-D1, was active in the two low amylose cultivars. These mutants were termed “partial waxy mutants” and considered to be very useful material for breeding waxy wheat.  相似文献   

13.
翟红梅  田纪春 《作物学报》2007,33(7):1059-1066
以小麦品种藁城8901为母本,糯麦1号为父本,用“单粒传”法构建了一个含有8种Wx基因突变类型的重组自交系群体 (RIL) 。应用改良的SDS-PAGE方法对RIL-7的Wx基因突变类型进行检测,发现在228个株系中,正常类型的株系有34个,Wx-A1突变体为26个,Wx-B1突变体为32个,Wx-D1突变体30个,Wx-A1和Wx-B1位点同时突变的有28个,Wx-A1和Wx-D1位点同时突变的有20个,Wx-B1和Wx-D1位点同时突变的为28个,3个Wx基因位点均突变的为16个。卡方测验证明,3个Wx基因位点的突变符合孟德尔遗传规律,属于质量性状遗传。田间试验表明,8种类型之间在初花期、株高和穗粒数上无显著差异,但在穗长、每穗小穗数和千粒重上Wx-A1突变型显著低于其他7种类型,而7种类型间无显著差异。淀粉特性研究表明,不同Wx蛋白缺失显著影响直链淀粉含量、淀粉糊化特性和淀粉凝胶的质构剖面分析 (TPA) 特性。正常类型的直链淀粉含量最高(20.8%),糯麦的最低(1.1%)。糯麦淀粉的峰值黏度和稀澥值较高,但其低谷黏度、最终黏度和反弹值较低,与其他缺失类型间差异达5%显著水平。凝胶的TPA测试表明,随着直链淀粉含量的降低,凝胶的硬度、黏着性、弹性、胶着性和咀嚼性显著降低,而黏聚性和回复性显著升高。直链淀粉含量与糊化特性的低谷黏度、最终黏度、反弹值、峰值时间和糊化温度之间正相关达1%显著水平(r=0.892~0.965),与峰值黏度、稀澥值呈1%水平负相关( r=－0.892, r=－0.945);直链淀粉含量与凝胶TPA参数的黏聚性、回复性呈极显著负相关(r=－0.928, r=－0.829),与凝胶的硬度、黏着性、弹性、胶着性和咀嚼性呈极显著正相关( r=0.869~0.979)。  相似文献   

14.
The granule-bound starch synthase (GBSS I) encoded by the Wxgenes, is involved in amylose synthesis. For analyses of mechanisms of amylose synthesis and associated starch properties in hexaploid wheat, eight possible genotypes having different combinations of the three null alleles at the Wx loci with a common genetic background are a prerequisite. A near-isogenic population of doubled haploid (DH) lines was produced from Chinese Spring × waxy Chinese Spring F1 plants using the wheat × maize method. The Wx protein phenotypes of the DH progeny were examined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and found that the null alleles at each of the three Wx loci segregated in a Mendelian fashion. A field trial demonstrated no differences between the eight types for ear emergence time, plant height and grain yield traits. Amylose content in the endosperm starch was highest in the wild type while lowest in the waxy type having no Wx proteins. Comparison between single null types and double null types indicated that the amylose synthesis capacity of Wx-A1a allele is the lowest. Pasting properties of starch are the highest in the waxy type, followed by the double null types. Consequently, both peak viscosity and breakdown were negatively correlated with amylose content. The chain-length distribution analysis of amylopectin structure revealed no clear difference among the eight types,suggesting that the reduced GBSS I activity due to introgression of the null Wx alleles does not affect either the chain length or the degree of branching of amylopectin. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

15.
A collection of 63 bread wheats (Triticum aestivum L.) and 21 durum wheats (Triticum durum Desf.) commonly grown in Portugal since 1982 were characterized for the composition of wheat storage proteins (WSP), high molecular weight glutenin subunits (HMW-GS), low molecular weight glutenin subunits (LMW-GS) and ω-gliadins. The composition of HMW-GS, LMW-GS and &-gliadins, encoded at loci Glu-1, Glu-3 and Gli-1, respectively, was revealed by sodium dodecyl sulphate polyacrylamide gel electrophoresis. WSP allelic compositions of bread and durum wheat patterns were given. In the bread wheats, a total of 24, 24 and 18 patterns were observed for HMW-GS, LMW-GS and ω-gliadins, respectively. Forty-two different alleles were identified for the nine loci studied, Glu-A1 (3), Glu-B1 (7), Glu-D1 (4), Glu-A3 (5), Glu-B1 (7), Glu-D3 (2), Gli-A1 (2), Gli-B1 (8) and Gli-D1 (4). In the case of durum wheats, 19 alleles were identified: one allele at Glu-A1, two at Glu-B3, Glu-B2 and Gli-A1, three at Glu-B1, four at Glu-A3 and five at Gli-B1. For HMW-GS, LMW-GS and ω-gliadins, three, six and six different patterns were revealed, respectively. This study represents the first attempt to discriminate the bread and durum wheat varieties commonly grown in Portugal by the allelic variation of storage proteins. The database is useful for varietal identification and for plant breeders who seek to devise effective programmes aimed at improving wheat quality.  相似文献   

16.
V. Vallega 《Plant Breeding》1988,100(4):241-246
Variation in high-molecular-weight glutenin subunit composition amongst Triticum durum cvs. of different origins was investigated by SDS-PAGE and compared with that reported for T. dicoccum and T. aestivum. Tetraploid wheat collections (408 cvs.) were found to carry nearly twice as many Glu-A1 and Glu-B1 alleles as a hexaploid wheat sample of comparable size. In each of the taxa considered, allelic variation at the Glu-B1 locus was markedly greater than that observed for Glu-A1. However, because all the Glu-B1 subunits so far discovered exhibit a restricted and distinctive mobility range during. SDS-PAGE, it is suggested that they are derived from a single source, possibly from Aegilops searsii. Most durum cvs. carried a ‘null’Glu-A1 allele and therefore fewer subunits than dicoccums and common wheats. It is argued that differences in the frequency of occurrence of ‘null’Glu-1 alleles between taxa probably resulted from random samplings made by early agriculturalists and breeders, rather than from an inherent tendency of polyploid wheats to suppress the activity of “redundant” genes.  相似文献   

17.
Soft rice with low amylose content (AC) ranging by 5–15% is a unique type with special eating and appearance quality and has become popular in the rice market. We resequenced the Wx‐mp, a key allele from Milky Princess, a Japanese low AC variety, and found that the +473 mutation in exon 4 is the key mutation in both Wx‐mp and its ancestor allele, Wx‐mq from Milky Queen. Based on this functional mutation, an allele‐specific PCR (AS‐PCR) marker was developed and proven in a breeding population derived from a cross between a Chinese late variety Nan Keng 46 (Wx‐mp/Wx‐mp) and an early line Ning 63121(Wx‐b/Wx‐b). Based on the marker‐aided selection by our newly developed AS‐PCR marker for Wx‐mp and the known ST10 marker for Stvb‐i, a total of 12 Wx‐mp homozygotes were selected from 198 F2 progenies, and four of them were immune to rice stripe virus (RSV) with averagely 11.3 days earlier heading than Nan Keng 46 without significant change in grain yield.  相似文献   

18.
To clarify the genetic mechanism which controls the variation in amylose content among nonwaxy landraces of foxtail millet, the inheritance of different starch types in endosperm was examined by I2-KI staining. The level of starch granule bound protein in foxtail millet endosperm was also analyzed using SDS-PAGE. The segregation for starch types in F2 and F3 seeds determined by I2-KI staining showed that there are three different alleles at the waxy (wx) locus. A major protein bound to starch granules was detected in nonwaxy endosperm but it was absent in most of the waxy endosperm, suggesting that the protein is the Wx gene product which is responsible for the synthesis of amylose in endosperm. The level of Wx protein proportionally corresponded to the amylose content among nonwaxy landraces. This implies that two different Wx alleles regulate quantitative levels of Wx protein. Landraces with the allele for low amylose content are from Taiwan, the Philippines, Indonesia and Thailand. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
Cadmium (Cd) is a toxic heavy metal that occurs naturally in soils. Durum wheat is known to accumulate generally more Cd than other cereal crops. The uptake of Cd in durum wheat is governed by the gene Cdu1, which co‐segregates with several DNA markers, such as the co‐dominant marker usw47 and the dominant marker ScOPC20. A panel of 314 durum wheat cultivars or lines originating from 16 countries or regions were assessed with usw47. The plant material was mainly comprised of cultivars and modern breeding lines. From this set, 165 durum wheat lines were classified as low‐Cd accumulators, 144 high‐Cd accumulators and five were heterogeneous. A smaller subset of 16 cultivars had previously been evaluated for Cd accumulation in replicated field trials. Lines with the high‐Cd allele showed a 2.4‐fold higher Cd content in the seeds than lines with the low‐Cd allele. We also compared the utility of markers usw47 and ScOPC20 as selection tools. Marker‐assisted selection appears as a robust and practicable tool for breeding durum cultivars with low‐Cd content.  相似文献   

20.
X. K. Zhang    L. Liu    Z. H. He    D. J. Sun    X. Y. He    Z. H. Xu    P. P. Zhang    F. Chen    X. C. Xia 《Plant Breeding》2008,127(2):109-115
Wheat quality properties are genetically determined by the compositions of high and low molecular weight glutenin subunits, grain hardness, polyphenol oxidase (PPO) activity and starch viscosity. Two multiplex PCR assays were developed and validated using 70 cultivars and advanced lines from Chinese autumn‐sown wheat regions. Multiplex PCR I includes molecular markers for genes/loci ω‐secalin, Glu‐B1‐2a (By8), Glu‐D1‐1d (Dx5), Glu‐A3d, Glu‐B3 (for non‐1B·1R type) and Pinb‐D1b targeting improved gluten parameters and pan bread quality. Multiplex PCR II comprises markers for genes/loci Ppo‐A1, Ppo‐D1 and Wx‐B1b targeting improved noodle quality. The results were consistent with those achieved by SDS‐PAGE and RP‐HPLC, indicating that the two multiplex assays were highly effective, with good repeatability and low costs enabling their use in wheat breeding programmes. In total, nine alleles (subunits) at locus Glu‐B1, four at Glu‐D1 and five at Glu‐A3 locus were identified, and the alleles (subunits) Glu‐B1b (7 + 8), Glu‐B1c (7 + 9), Glu‐D1a (2 + 12), Glu‐D1d (5 + 10), Glu‐A3a, Glu‐A3c and Glu‐A3d were most frequently present in the cultivars and lines tested. The 1B·1R translocation was present in 28 (40.0%) lines, whereas the Wx‐B1 null allele for better noodle quality was present in only seven (10.0%) cultivars and advanced lines, and 37 (52.9%) lines had Pinb‐D1b associated with hard grains. The allele Ppo‐A1b on chromosome 2AL associated with lower PPO activity was present in 38 (54.3%) genotypes, whereas the less effective allele Ppo‐D1a on chromosome 2DL, also associated with low PPO activity was present in 45 (64.3%) of genotypes. These two multiplex PCR assays should be effective in marker assisted selection targeting improved pan bread‐making and noodle qualities.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号