The high and low molecular weight glutenin subunits and ω-gliadin composition of bread and durum wheats commonly grown in Portugal

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.     

Genetic diversity of European spelt wheat (Triticum aestivum ssp. spelta L. em. Thell.) revealed by glutenin subunit variations at the Glu-1 and Glu-3 loci

Summary High and low molecular weight glutenin subunit (HMW-GS and LMW-GS) compositions of 270 European spelts, 15 Iranian spelts and 25 bread wheat cultivars were analyzed by one- and two-dimensional gel electrophoresis. The results revealed a total of 22 HMW-GS alleles (4 at Glu-A1, 11 at Glu-B1 and 7 at Glu-D1) and 32 allele combinations among the three Glu-1 loci. Two major genotypes of HMW-GS: 1, 13+16, 2+12 and 1, 6.1+22.1, 2+12 were found to occur in Central European spelt wheat cultivars and landraces at higher frequencies of 35 and 28%, respectively. The Glu-B1 locus displayed the greatest variation and genetic diversity index (H) was 0.69 whereas Glu-A1 and Glu-D1 showed H index values of 0.26 and 0.19, respectively. The dendrogram constructed by HMW and LMW glutenin subunit bands revealed that European spelts form a separated cluster from common wheat suggesting that spelt and common wheat form distinct groups. In addition, all 15 Iranian spelt land variety accessions differed from European spelts and possessed similar HMW-GS alleles to common wheat. Because of a wider polymorphism Central European spelt wheats are an important genetic reserviour for improving common wheat quality. Both authors contributed equally to this work     

HMW-GS和LMW-GS组成及1BL/1RS易位对春小麦品质性状的影响

分析了221份春小麦品种（系）的HMW-GS、LMW-GS组成和1BL/1RS易位状况,并用其中104份品种（系）研究了HMW-GS和LMW-GS等位变异及1BL/1RS易位对品质性状的影响。结果表明,1、7+9、5+10、GluA3a和GluB3j分布较广,频率分别为57.5%、45.2%、63.8%、29.0%和42.5%。1BL/1RS易位系相当普遍,西北春麦区和东北春麦区频率分别为44.3     

High molecular weight glutenin subunits of current bread wheats grown in Iran

Variation of high molecular weight gluteninsubunits (HMW-GS) at the Glu-1 lociwas studied using SDS-PAGE method in 43advanced lines or cultivars commonly grownin Iran. Fourteen alleles and 21 alleliccompositions were detected. Among the 43bread wheats analysed only five showed aunique HMW-GS composition. The mostfrequent HMW-GS patterns were 2^*, 7+8,2+12 and 2^*, 17+18, 2+12 which wereobserved in 13 and six cultivars,respectively. In the remainings, each twoto three lines or cultivars showed a commonHMW-GS pattern. Therefore, allelicvariation at Glu-1 loci is of limitedvalue for cultivar identification comparedwith loci controlling gliadins. Sevencultivars were observed to consist of twoto three biotypes with different alleles.In cultivar Mahdavi a biotype showedinactivity at the Glu-B1 locus. Analready reported rare subunit pair'2^***+12' at Glu-D1locus was found in cultivar Kavir. Theresults of scoring cultivars for theirquality based on the HMW-GS compositionswith an average score of eight, wasgenerally good. Cultivars Inia, Tajan, andadvanced lines N-75-11 and N-75-15 showedquality score equal to 10, whereas Alamootand C-75-5 showed quality scores equal tofive. The quality of former and latterlines and cultivars were considered highestand lowest, respectively. The resultsobtained in this study are useful inbreeding programs to improve bread makingquality, developing uniformity andimproving heterogeneous cultivars by meansof selection of the best genotypes.     

Biochemical and molecular characterisation of Glu-1 loci in Argentinean wheat cultivars

The high molecular weight glutenin subunit (HMW-GS) composition of acollection of 107 Argentinean bread wheat cultivars was analysed bysodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE).Allelic variation at the Glu-1 loci was identified and its frequencycalculated. Eleven alleles were detected, three encoded at the Glu-A1locus, six at the Glu-B1 locus and two at the Glu-D1 locus. Alow frequency of the null allele at the Glu-A1 locus and a highfrequency of subunits 5+10 at the Glu-D1 locus were observed.Reversed phase-high performance liquid chromatography (RP-HPLC)analysis was used to further characterise HMW-GS. Two different types ofBx subunit 8 (named subunits 8 and 8) were detected, the latterhaving shorter elution time. Subunit 8 was not identifiable bySDS-PAGE. According to quantification by RP-HPLC analysis, two groupsof subunit 7 were observed. One group, with a relatively high proportionof subunit 7 (approximately 39% of the total amount of HMW-GS)appeared in cultivars with allele 7+8 at the Glu-B1 locus; asecond group of subunit 7 (around 24% of the total amount ofHMW-GS), was found in alleles 7+8, 7+8 and 7+9. Restrictionfragment length polymorphisms (RFLP) analyses of HMW-GS genes werealso carried out after digestion of genomic DNA with HindIII andTaqI restriction enzymes. The relationship between DNA fragment sizeand glutenin subunits, as estimated by electrophoretic mobility inSDS-PAGE, was also examined. The restriction enzyme TaqIdemonstrated to be a useful tool to detect homozygous plants in selectionprograms against the Glu-A1 null allele.     

Sources of resistance to tomato spotted wilt virus (TSWV) in cultivated and wild species of Capsicum

Summary The high molecular weight (HMW) subunits of glutenin extracted from flour of 36 Yogoslav wheat cultivars were separated by SDS-PAGE to identify their alleles, and the frequency of each allele was calculated. Eleven alleles from the three Glu-loci were recognized, three at the Glu-A1 locus, six at the Glu-B1 locus and two at the Glu-D1 locus. The most frequent allele was a (55.5%) from Glu-D1, which controls synthesis of subunits 2+12. The Glu-1 quality score varied from 4 (KG-III/27, KG-75, Morava and KG-101/7) to 10 (Lepenica). The mean Glu-1 quality score of cultivars and lines from Kragujevac was 6.8, for cultivars from Zagreb 7.2, and for cultivars from Novi Sad was 7.9. Most of the genotypes with a quality score of 8 or above, had high sedimentation values (Zeleny test). There were no significant differences in allelic composition at the Glu-1 loci among wheat genotypes from Kragujevac, Novi Sad and Zagreb.     

冬小麦高、低分子量麦谷蛋白亚基形成时间和积累强度及其与沉降值的关系

采用6个不同品质类型冬小麦品种研究高、低分子量麦谷蛋白亚基形成时间和积累强度及其与沉降值的关系。结果表明, 在籽粒形成过程中,各品种的高分子量谷蛋白亚基（HMW-GS）开始形成时间及形成速度不同,低分子量谷蛋白亚基（LMW-GS）B区在花后10 d基本形成;随着籽粒发育,HMW-GS和LMW-GS的类型和积累量都逐渐增多。强筋小麦     

Allelic variation and genetic diversity of high molecular weight glutenin subunit in Chinese endemic wheats (Triticum aestivum L.)

The high molecular weight glutenin subunit (HMW-GS) compositions of 66 Chinese endemic wheats were determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Ten alleles at the Glu-1 loci were detected in 50 Tibetan weedrace wheat accessions which in combination resulted in seven different HMW-GS patterns. Four HMW-GS patterns were observed among 10 Yunnan hulled wheat accessions, and two patterns in six Xingjiang rice wheat accessions. Two novel alleles (Bx7** + By8, Bx7 + By8**) and two rare alleles (Dx2 + 1Dy12*, Dx2 + null) were found in Tibetan weedrace accessions, with one of the latter (Dx2 + Dy12*) also being found in Yunnan hulled wheat. The mean indices of genetic variation at the Glu-1 loci in Yunnan hulled wheat, Tibetan weedrace wheat and Xingjiang rice wheat were 0.2232, 0.1655 and 0.0926, respectively, showing that Yunnan hulled wheat and Tibetan weedrace wheat had higher genetic variation than Xingjiang rice wheat.     

低分子量谷蛋白亚基GlU-A3和GlU-B3位点对小麦面筋强度和烘焙特性影响

低分子量谷蛋白亚基是小麦谷蛋白亚基的重要组成部分,黄淮麦区小麦低分子量谷蛋白亚基组成对品质的效应尚缺乏系统的研究。本研究采用SDS-PAGE方法,鉴定了黄淮麦区42个小麦品种的Glu-A3位点和Glu-B3位点低分子量谷蛋白亚基组成,分析了低分子量谷蛋白亚基对小麦面筋强度和烘烤品质的影响。结果表明,在Glu-A3位点,对面筋强度和面包烘焙品质正向效应为:d,b>a,e;在Glu-B3位点,对面筋强度正效应为:h,d>f>g,b,j,对面包烘焙品质正向效应为:h>f,d>g,b,j。Glu-A3d/Glu-B3h亚基组合具有较好的面筋强度和烘焙品质。就低分子量谷蛋白亚基单个变异位点对品质综合效应而言,Glu-B3位点对品质作用比较大,与Glu-B1位点相近,同时,高低分子量谷蛋白亚基之间存在着互作效应,以Glu-B1/Glu-A3和Glu-D1/Glu-B3位点的互作效应比较显著。Glu-A3和Glu-B3位点及其所编码的不同亚基种类对品质的效应差异显著,并且与高分子量谷蛋白亚基位点存在互作,对不同位点优质亚基的聚合将有助于小麦品质的遗传改良。     

Genetic diversity of wheat storage proteins and bread wheat quality

To understand the genetic and biochemical basis of the bread makingquality of wheat varieties, a large experiment was carried out with a set of162 hexaploid bread wheat varieties registered in the French or EuropeanWheat Catalogue. This material was used to analyse their allelic compositionat the twelve main storage protein loci. A large genetic and biochemicaldiversity of the gluten proteins was found. Several gliadin encoding lociexhibited the highest allelic diversity whereas the lowest diversity was foundfor Glu-A1 and Glu-D3 loci encoding some high molecularweight glutenin subunits (HMW-GS) and LMW-GS respectively. Thevarieties were grown in three experimental locations in France. Qualityevaluation was carried out from material harvested in each location usingseven technological tests: grain protein content (Prot), grain hardness(GH), Zeleny sedimentation test (Zel), Pelshenke test (Pel), water solublepentosans (relative viscosity: Vr ), mixograph test (giving 11 parameters)and the alveograph test (dough strength W, tenacity P , extensibility L,swelling G, ratio P/L and the elasticity index Ie). Genetic and locationeffects as well as broad-sense heritability of each of the 22 technologicalparameters were calculated. GH, corresponding to the major Ha gene, Pel,and MtxW (mixograph parameter) had the highest heritability coefficients,alveograph parameters like W, P, the relative viscosity Vr and severalmixograph parameters had medium heritability coefficients whereas Protand L had the lowest. Variance analysis (using GLM procedure) allowed theeffect of the allelic diversity of the storage proteins, on the geneticvariations of each quality parameters, to be estimated. Glu-1 and Glu-3 loci had significant additive effects in the genetic variations of manyparameters. Gliadin alleles encoded at Gli-1 and Gli-2 were alsofound to play significant effect on several quality parameters. The majorpart of the phenotypic variation of the different quality parameters like Zel,Pel, W or mixograph peak time MPT was explained with the GH and allelesencoded at Glu-1 and Glu-3. Allelic variants encoded at Glu3and Gli-2 had similar contribution to the phenotypic variations ofquality parameters and accounted for 4% up to 21% each.     

小麦资源胚乳蛋白Glu-1、Glu-3、Gli-1基因位点变异特点

141个普通小麦品种及农家种中，由Glu-1位点控制的高分子量谷蛋白亚基共27种图谱，最常见的图谱是（N，7+8，2+12）占22%和（N，7+9，2+12）占19.9%，Glu-A1、Glu-B1、Glu-D1位点控制的均为正效应亚基，其图谱（1，7+8，5+10），（1，14+15，5+10），（1，13+16，5+10），（1，17+18，5+10），（2*，7+8，5+10），（2*，13+16，5+10）占13.4%; 由Glu-3位点控制的低分子量谷蛋白亚基共48种以上的图谱，最常见的图谱是（a, j, c）, Glu-A3位点存在6个以上等位基因，新发现的占5.7%, Glu-B3位点存在10个以上等位基因，新发现的占2.8%, Glu-D3位点存在3个等位基因；由Gli-1位点控制的醇溶蛋白共81种以上图谱，Gli-1A1位点存在7个以上等位基因，新发现的占7.1%, Gli-B1位点存在12个以上等位基因，新发现的等位基因占3.5%, Gli-D1位点存在10个等位基因，Gli-B1位点的l为1B/1R易位系，占总数的33.6%; 由Gli-1位点控制的醇溶蛋白和由Glu-3位点控制的低分子量谷蛋白亚基基因变异远比由G1u-1位点控制的高分子量谷蛋白亚基复杂和丰富。     

小麦地方品种高分子量谷蛋白亚基多样性分析

采用SDS-PAGE方法,对我国9个麦区的76份代表性地方品种的高分子量谷蛋白亚基(HMW-GS)组成比较分析,并探讨其与环境因素(平均海拔、年平均降雨量和年平均温度)的相关性。结果表明,25.0%的品种具有异质性,分别包含2~4种不同HMW-GS组合;在Glu-1位点共检测到14个等位变异,其中Glu-A1、Glu-B1和Glu-D1等位变异数分别为2、7和5;发现了3个新等位变异,包括Glu-B1位点2个和Glu-D1位点1个。所有等位变异构成16种不同的亚基组合类型,以(N, 7+8, 2+12)为主,频率为69.7%。在Glu-1位点上,不同麦区遗传多样性分布存在一定的不均衡性,年平均降雨量和年平均温度与麦区多样性指数呈负相关。推测环境压力可能是地方品种多样性地区分化的重要因素。     

Glu-1位点缺失对小麦麦谷蛋白聚合体粒度分布及面团特性的影响

以Glu-1位点正常和部分缺失的小麦品系为材料,探讨HMW-GS和LMW-GS组成与谷蛋白聚合体粒度分布和面团特性的关系,为利用HMW-GS缺失系改良小麦品质提供理论依据。在20个供试硬白冬麦品系中,1个品系为Glu-A1位点缺失,5个品系为Glu-D1缺失,3个品系为Glu-A1和Glu-D1双缺失。所有品系的蛋白质含量皆较高(13.39%~14.12%),品系间无显著差异,缺失系与非缺失系间也无显著差异。Glu-1位点缺失显著降低了高分子量谷蛋白/低分子量谷蛋白比(HMW/LMW)、不溶性谷蛋白大聚体的含量和百分比。谷蛋白/醇溶蛋白比(GLU/GLI)在基因型间变幅较小,且在缺失系和非缺失系间无显著差异。Glu-1位点缺失显著降低了面团弹性,但显著提高了面团的延展性。部分Glu-1位点缺失系仍具有较高的面团强度和突出的延展性,谷蛋白聚合体粒度分布和面团特性受谷蛋白亚基组成和表达量的共同影响。研究结果表明,利用Glu-1位点亚基缺失可能是改善面筋延展性,提高食品加工品质的方法之一。     

Allelic variation and composition of HMW-GS in advanced lines derived from d-genome synthetic hexaploid / bread wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.)

The objective of this study was to identify allelic variations at Glu-1 loci of wheat (Triticum aestivum L.) advanced lines derived from hybridization of bread wheat and synthetic hexaploid wheats (2n = 6x = 42; AABBDD). Locally adapted wheat genotypes were crossed with synthetic hexaploid wheats. From the 134 different cross combinations made, 202 F₈ advanced lines were selected and their HMW-GS composition was studied using SDS-PAGE. In total, 24 allelic variants and 68 HMW-GS combinations were observed at Glu-A1, Glu-B1, and Glu-D1 loci. In bread wheat, the Glu-D1 locus is usually characterized by subunits 1Dx2+1Dy12 and 1Dx5+1Dy10 with the latter having a stronger effect on bread-making quality. The subunit 1Dx5+1Dy10 was predominantly observed in these advanced lines. The inferior subunit 1Dx2+1Dy12, predominant in adapted wheat germplasm showed a comparative low frequency in the derived advanced breeding lines. Its successful replacement is due to the other better allelic variants at the Glu-D1 locus inherited in these synthetic hexaploid wheats from Aegilops tauschii (2n = 2x = 14; DD).     

HMW-GS和LMW-GS组成对小麦加工品质的影响

高分子量麦谷蛋白亚基(HMW-GS)和低分子量麦谷蛋白亚基(LMW-GS)是决定小麦加工品质的重要因素。以小麦品种PH82-2(亚基组成1, 14+15, 2+12和Glu-A3d, Glu-B3d, Glu-D3c)和内乡188(亚基组成1, 7+9, 5+10和 Glu-A3a, Glu-B3j, Glu-D3b)的242份F₃和F₄株系(试验I)和91份产量比较试验材料(试验II)研究了贮藏蛋白组成对小麦加工品质的影响。结果表明,HMW-GS和LMW-GS等位变异对籽粒蛋白质含量的影响不大,但对加工品质均有极显著影响(P<1%)。就位点的效应而言,Glu-D1位点对加工品质的效应较大,而Glu-D3位点的效应较小。就单个亚基而言,在Glu-B1位点,14+15<7+9;在Glu-D3位点,Glu-D3c>Glu-D3b。1B/1R易位系的部分品质性状,如和面时间、曲线下降斜度和峰积分好于非1B/1R易位系。     

利用HMW-GS全缺失突变体快速构建Glu-1位点近等渗入系

小麦高分子量麦谷蛋白亚基(highmolecular weight glutenin subunit, HMW-GS)由Glu-A1、Glu-B1、Glu-D1位点中含有的复等位基因编码,评价和优化Glu-1位点组合是认识与改良HMW-GS表达与功能的重要途径。本研究创制了以小偃81为背景的HMW-GS基因完全缺失突变体DLGlu1。将DLGlu1与加拿大优质强筋小麦品种Glenlea杂交,结合后代幼胚培养与分子标记辅助选择技术,在BC₃F₃种子中快速鉴定出来自Glenlea的Glu-A1a、Glu-B1al和Glu-D1d位点不同组合的7种渗入系材料,可进一步发展成一套完整的Glu-1位点有差异的近等渗入系。本研究表明,DLGlu1可用于Glu-1位点近等渗入系的快速创制,对Glu-1位点功能研究和改良具有重要价值。     

小麦Glu-1位点变异和1B/1R易位对谷蛋白亚基表达量和面包加工品质的影响

选用北方冬麦区近年来育成的优质强筋品种及山东省主栽品种共42份, 采用反相高效液相色谱法(RP-HPLC)和凝胶色谱法(SE-HPLC)对小麦贮藏蛋白组分进行量化, 分析了不同高分子量谷蛋白亚基(HMW-GS)组成对其表达量、面团流变学特性和面包加工品质的影响。结果表明, Glu-D1位点对谷蛋白亚基含量和加工品质的加性效应最大, 达5%显著水平, 贡献率为28.5%~71.3%。在Glu-A1和Glu-D1位点, 单个亚基对谷蛋白亚基含量和加工品质的贡献分别为1>2*>N和5+10>2+12>4+12, 而在Glu-B1位点, 则表现为差异不显著。不同亚基组合的HMW–GS表达量差异达5%显著水平, 相同亚基组合的品种间贮藏蛋白组分表达量的变异较大, 亚基表达量的差异可能是导致品种间品质差异的重要原因。1B/1R易位显著降低LMW-GS、谷蛋白总量和%UPP, 导致加工品质变劣。选择具有优质亚基组合, 且谷蛋白亚基表达量高的类型, 是有效改良面筋强度, 进一步提高优质新品种选育的有效途径。     

Allelic variation at the <Emphasis Type="Italic">Glu-1</Emphasis> and <Emphasis Type="Italic">Glu-3</Emphasis> loci,presence of the 1B.1R translocation,and their effects on mixographic properties in Chinese bread wheats

Allelic variations at the Glu-1 and Glu-3 loci play an important role in determining dough properties and bread-making quality. Two hundred and fifty-one cultivars and advanced lines from four major Chinese wheat-producing zones in the autumn-sown wheat regions were used to investigate the high-molecular-weight glutenin subunits (HMW GS) and low-molecular-weight glutenin subunit (LMW GS) composition controlled by the Glu-1 and Glu-3 loci, respectively, as well as the presence of the 1B.1R translocation, and to determine the association of storage protein composition with protein content, SDS sedimentation value, and dough-mixing properties measured by mixograph. Three, nine, and four allelic variations were present at Glu-A1, Glu-B1, and Glu-D1, respectively. Subunits 1, N, 7+8, 7+9, and 2+12 are the dominant HMW GS, with frequencies of 51.3, 39.4, 38.2, 45.0, and 59.8%, respectively. Five and eight allelic variations were present at the Glu-A3 and Glu-B3 loci (data of Glu-D3 were not available), Glu-A3a, Glu-A3d, Glu-B3j (presence of the 1B.1R translocation), and Glu-B3d are the dominant LMW GS, with frequencies of 37.1, 31.7, 44.6, and 20.3%, respectively. The frequencies of allelic variation at Glu-1 and Glu-3 differ greatly in different regions. The effects of HMW GS and LMW GS on SDS sedimentation value, mixing time, and mixing tolerance were significant at P = 0.01, with Glu-D1 and Glu-B3 showing the largest contributions to mixing time and mixing tolerance. Averaged data from two locations showed that the quality effects of glutenin loci could be ranked as Glu-B3 > Glu-B1 > Glu-A1 > Glu-D1 > Glu-A3 for SDS sedimentation value, Glu-D1 > Glu-B3 > Glu-A1 = Glu-B1 = Glu-A3 for mixing time, and Glu-D1 > Glu-B3 = Glu-B1 > Glu-A3 > Glu-A1 for mixing tolerance, respectively. The significant and negative effect of the 1B.1R translocation on dough properties was confirmed. It was concluded that the high frequency of undesirable HMW GS and LMW GS and the presence of the 1B.1R translocation are responsible for the weak gluten property of Chinese germplasm; hence, reducing the frequency of the 1B.1R translocation and integration of desirable subunits at Glu-1 and Glu-3 such as 1, 7+8, 14+15, 5+10, Glu-A3d, and Glu-B3d, could lead to the improvement of gluten quality in Chinese wheats.     

Glu-1位点等位变异及表达量对麦谷蛋白聚合体粒度分布的影响

选用我国春播麦区23份(试验I)和北部冬麦区21份(试验II)品种(系),研究了Glu-1位点等位变异及其亚基表达量对谷蛋白聚合体粒度分布的影响。结果表明,Glu-1位点等位变异及其亚基表达量显著影响谷蛋白聚合体的粒度分布,且影响程度受蛋白质含量,尤其是高分子量谷蛋白总量水平的影响。在高分子量谷蛋白总量较低时(试验I),Glu-B1和Glu-D1位点对不溶性谷蛋白大聚体含量(UPP)及其占聚合体蛋白总量的百分比(%UPP)的加性效应都达1%显著水平;Glu-B1和Glu-D1位点单个亚基对两者的贡献分别为7^OE+8^* >7+9 >17+18 >7+8和5+10 >2+12,具有5+10亚基组合的%UPP显著高于具有2+12的亚基组合。高分子量谷蛋白的亚基表达量与UPP含量呈高度正相关,相关系数为0.79~0.93(P < 0.01)。而在高分子量谷蛋白总量较高时(试验II),仅Glu-D1位点对%UPP的加性效应达5%显著水平,5+10亚基对%UPP的贡献显著高于2+12和4+12;亚基组合间的聚合体粒度分布无显著差异。高分子量谷蛋白的亚基表达量与UPP含量的相关系数为0.42~0.86(P < 0.05或0.01)。结合高分子量谷蛋白表达量和优质亚基进行选择,能有效提高不溶性谷蛋白大聚体的含量和相对比例,有利于面筋强度和加工品质的进一步提高。     

Multiplex-PCR typing of high molecular weight glutenin alleles in wheat

In Australian commercial cultivars, each high molecular weight glutenin (Glu-1) homoeologous locus consists of one of two predominant alleles: Glu-A1a (subunit Ax1) or Glu-A1b (subunit Ax2*) at the GluA1 locus, Glu-B1b (Bx7 and By8 subunits) or Glu-B1i (Bx17 and By18 subunits) at the Glu-B1 locus, and Glu-D1d (Dx5 and Dy10 subunits) or Glu-D1a (Dx2 and Dy12 subunits) at the Glu-D1 locus. PCR-based assays have been developed in this study to discriminate between these common alleles at each locus. Primers specific for the Glu-A1 Ax2* gene give a single fragment of 1319 bp only in the presence of this gene. Primers targeting the Glu-B1 locus resulted in a co-dominant marker for which the Bx7 genotype produced two fragments (630 bp and 766 bp) and the Bx17 genotype a single fragment (669 bp). The third pair of primers was specific for the Dx5 gene and resulted in a single band of 478 bp. A multiplexed PCR assay was established which permitted the discrimination of the major HMW glutenins in a single PCR reaction and agarose gel assay. As the HMW glutenin composition of a wheat line is extremely important in determining the functional properties of wheat gluten, these markers are useful for the purposes of marker-assisted breeding. These markers may also be useful for the purpose of DNA-based identification of wheat varieties. This revised version was published online in July 2006 with corrections to the Cover Date.