冬小麦品种的HMW-GS组成和1BL/1RS易位分布及其与品质性状的关系研究

研究了我国代表性冬小麦品种(系)高分子量麦谷蛋白亚基(HMW-GS)以及1BL/1RS易位的分布和组成,探讨了其对揉面仪特性等小麦加工品质性状的影响,结果表明:在Glu-A1位点,我国小麦品种中1亚基的频率为64.0%,N亚基为32.5%,2*亚基频率低,为3.5%;在Glu-B1位点,7 9亚基占56.8%,7 8亚基为26.4%,14 15亚基为10.7%,而20,13 16,7亚基的材料极少(频率分别为3.6%,1.5%和1%);在Glu-D1位点,2 12和4 12亚基合计占63.0%,而5 10亚基的比例偏低,为37.0%.1BL/1RS易位系的比例仍然偏高,为50.8%.HMW-GS组成及1BL/1RS易位对小麦加工品质影响较大,其中5 10亚基对小麦绝大多数加工品质指标起正向作用,而1BL/1RS易位对大多数品质指标起负向作用.因此,我国小麦品种5 10亚基的频率仍然偏低,1BL/1RS易位系频率仍然偏高,可能正是目前我国小麦生产中优质品种面筋强度不够,品质稳定性差的原因所在.根据SDS-PAGE麦谷蛋白电泳结果或分子标记进行优质高、低分子量麦谷蛋白亚基选择,提高5 10等优质亚基的比例,并根据醇溶蛋白电泳结果进行1BL/1RS易位筛选,降低1BL/1RS频率,应成为今后我国优质小麦育种的重要目标和手段之一.     

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。     

强筋小麦分子标记多重PCR体系的构建与应用

面筋强度与小麦高低分子量谷蛋白亚基种类(组合)密切相关。以12个已知亚基基因组成的品种为对照,选用基因(位点)Axnull、Bx7^OE、Dx5、Glu-A3d、Glu-B3i和Glu-B3的标记,构建多重PCR体系。以该体系检测对照的结果与已知基因型完全一致,一次PCR可同时间接检测7个与强筋有关基因(位点)Ax1/Ax2^*、Bx7^OE、Dx5、Glu-A3d、Glu-B3i和Glu-B3。对62个陕西小麦品种的检测结果表明,优质强筋亚基基因(位点)Ax1/Ax2^*、Dx5、Glu-A3d、Glu-B3i和Glu-B3的比例依次为56.5%、9.6%、33.9%、1.6%和64.4%,所有品种均不含Bx7^OE,携带0、1、2和3个及以上基因(位点)的品种分别占6.5%、33.9%、48.3%和11.3%。说明聚合多个强筋亚基基因(位点)的品种频率较低,通过优质亚基基因的聚合育种,可望改善陕西小麦品种的面筋品质。本研究所构建的强筋小麦分子标记检测的多重PCR体系检测结果稳定且可靠,可用于小麦种质资源的快速评价和强筋小麦分子辅助选育。     

小麦育种亲本材料Dx5、Bx14亚基及1BL/1RS易位的分子检测

为给小麦优质育种的亲本选配等研究提供参考,利用优质谷蛋白Dx5、Bx14亚基及1BL/1RS易位的特异性分子标记,对本课题组近年常用的38份杂交亲本材料进行了分子检测.结果表明,在引进品种和自育品种(系)中,含Dx5亚基的材料分别占16.0％和7.7％,含Bx14亚基的材料分别占16.0％和23.1％,1BL/1RS易位材料分别占24.0％和38.5％.与引进品种相比,自育品种(系)含Dx5亚基的材料很少,而含Bx14亚基和1BL/1RS易位的材料较多.总体来看,育种亲本含Dx5、Bx14亚基的材料较少,而含1BL/1RS易位的材料相对较多.因此,今后小麦优质育种中应重视含Dx5、Bx14亚基材料的引进和利用,合理使用1BL/1RS易位材料,并加强杂种后代的分子鉴定与选择.     

利用揉面特性鉴定小麦1BL/1RS易位系

1BL/1RS易位系曾广泛用于小麦农艺性状改良,但对加工品质有明显的负面影响。利用404份F₅至F₈高代品系(试验I)和175份山东省主栽品种及高代品系(试验II),研究1BL/1RS易位对小麦揉面参数的影响,分析不同高低分子量蛋白亚基(HWM/LWM-GS)背景下1BL/1RS的揉面特性,探讨利用揉面特性鉴定1BL/1RS易位系的方法。结果表明,1BL/1RS易位系的揉面时间、峰值带宽及峰后1 min带宽显著低于非1BL/1RS易位系,而衰落角和带宽比(峰值带宽/峰后1 min带宽)显著高于非1BL/1RS易位系,说明1BL/1RS易位导致小麦的揉面特性显著变劣。易位系的揉面谱带的主要特征为峰后1 min谱带急剧衰落并变窄,带宽比显著增大,而非1BL/1RS易位系的峰后谱带衰落、变窄平缓或者稳定时间较长,带宽比较小。带宽比1.6可作为判断易位系的有效指标,即大于或等于1.6为1BL/1RS易位系,小于1.6为非1BL/1RS易位系,准确率达85.2%(试验I)和96.8%(试验II)。尽管优质HWM-GS背景对Glu-B3j(1BL/1RS易位系)的揉面特性有一定正向补偿作用,但品质特性仍显著劣于其他Glu-B3位点,带宽比表现尤为突出。因此,揉面特性不仅能测定育种材料的面团流变学特性,而且还能有效鉴别1BL/1RS易位系。     

小麦高分子量谷蛋白亚基间的互补效应对面包加工品质的影响

利用偃展1号的10个HMW-GS近等基因系,研究了不同HMW-GS基因对面包烘烤品质的效应。两年的品质测试结果基本一致,说明所用近等基因系是评价亚基组成对加工品质影响的较理想材料。不同HMW-GS组成对面包评分影响较大,变异系数达到21.5%。相关分析表明,面包体积与形成时间(r = 0.90, P < 0.01)、沉淀值(r = 0.89, P < 0.01)、稳定时间(r = 0.67, P < 0.05)和面粉蛋白质含量(r = 0.52, P < 0.05)均达显著正相关;面包评分与面包体积(r = 0.98, P < 0.01)、沉淀值(r = 0.93, P < 0.01)、形成时间(r = 0.89, P < 0.01)也呈显著正相关。Glu-A1位点1Ax1基因的表达可以提高多数品系的面包评分;当Glu-A1位点是Null、Glu-D1位点是5’+12时,Glu-B1位点等位变异的面包加工品质效应为7+8 > 14+15 > 6+8 > 7,而当Glu-A1位点是1号亚基、Glu-D1位点是5’+12时,Glu-B1位点的等位变异的面包品质效应为6+8 > 14+15 > 7;当Glu-A1位点是Null时,14+15与5+10组合优于与5’+12组合,7+8与5’+12组合优于与5+10组合;1Dx5基因的沉默显著降低面包烘烤品质,HMW-GS对面包品质的作用似乎在X-亚基和Y-亚基之间存在一定的配合效应,任何一种基因的缺失或沉默都会造成品质的明显下降。     

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。     

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。     

小麦-黑麦远缘杂交后代高分子麦谷蛋白亚基变异分析

采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE) 方法, 分析了小麦-黑麦远缘杂交后代的66个株系的高分子量谷蛋白亚基(HMW-GS) 组成.结果表明:(1)在29个母本为MY 11的株系中,有6个株系的Glu-1等位基因相对于母本MY 11发生了变异,1 B/1 R易位系中Glu-1位点发生变异的频率为66.67%,非1 B/1 R易位系中Glu-1位点发生变异的频率为8.69%.在36个母本为A 42912株系中,3个株系的Glu-1等位基因发生变异且这3个株系皆为1 B/1 R易位系,1 B/1 R易位系中Glu-1位点发生变异的频率为60.0%,非1 B/1 R易位系Glu-1位点没有变异;(2)对于母本为MY 11的株系,Glu-1三个位点上等位基因的变异均只有2种,即Glu-A 1 a(86.20%)、Glu-A 1 c(13.79%)、Glu-B 1 b(89.65%)、Glu-B 1 c(10.34%)、Glu-D 1 a(3.45%)、Glu-D 1 d(96.55%).对于母本为A 42912的株系,仅在Glu-B 1位点发生变异,即Glu-B 1 b(91.66%)、Glu-B 1 c(8.33%);(3)供试株系共出现6种高分子谷蛋白亚基组合,即(1,7 8,5 10)、(Null,7 8,5 10)、(Null,7 9,5 10)、(Null,7 8,2 12)、(1,7 8,5 10)、(1,7 9,5 10),两种母本不同的株系类型均是母本型HMW-GS组合(1,7 8,5 10)占绝对优势.本文分析了1 B/1 R易位株系具有高频率HMW-GS变异的原因,并就这些材料在小麦优质育种中的利用策略作了探讨.     

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。     

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     

Cumulative and interaction effects of prolamin allelic variation and of 1BL/1RS translocation on flour quality in bread wheat

The allelic variation of prolamin loci was studied in three F₂ progenies from three crosses between the 1BL/1RS cultivar Triana and Yécora Rojo, Pavón and Florence Aurora, cultivars without the translocation. According to the 1:2:1 theoretical proportions observed in the allelic variants of the Glu-B3/Gli-B1 loci of the parent without the translocation, the inheritance as a block of the rye chromosome arm was confirmed. A group of F₃-F₄ recombinant lines, developed from these crosses was evaluated using the SDS-sedimentation test and the mixograph and alveograph tests. The presence of the 1BL/1RS translocation was not associated with significantly lower grain protein content values or with the optimum mixing time in the mixograph of the genotypes. The effect of the 1BL/1RS translocation on most of the quality parameters was highly dependent on the genetic pool. Significant increases in gluten strength and better mixing properties associated with the presence of some alleles of the Glu-A1, Glu-A3/ Gli-A1 and Gli-D2 loci were detected. The additivity and the interaction of prolamin gene effects with the rye translocation in the 1BL/1RS lines and its possible use in plant breeding are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

The effect ofGlu-B1 high molecular weight glutenin subunits on biscuit-making quality of wheat

Summary The aim of this study was to assess the effect of specificGlu-B1 HMW-GS on biscuit-making quality. Three soft spring wheat cultivars with the sameGlu-A1 andGlu-D1 HMW-GS, but differentGlu-B1 HMW-GS were used in crosses. F₂₄ derived lines were developed from these crosses.Glu-B1 HMW-GS 6+8 and 17+18; and 7+9 and 17+18 were compared. Lines with HMW-GS 6+8 versus those with HMW-GS 17+18 had a higher flour protein- and alveograph P/L ratio, shorter mixograph mixing time, more vitreous kernels, and a lower alveograph distensibility and strength (all values significant at p=0.05). Lines with HMW-GS 7+9 compared to those with 17+18 showed significant differences for flour extraction and biscuit diameter. The presence of HMW-GS 17+18 was significantly correlated with several biscuit-making quality characteristics in the Dirkwin/Zaragosa F₂₄ lines but not in the Waverley/Zaragosa F₂₄ lines, therefore the effect of HMW-GS 17+18 was modified by the genetic background in which they were expressed.     

小麦F4籽粒中Glu-1基因的遗传多态性

采用10％SDS—PAGE方法分析JY97—1／blosky和JY97—2／blosky各10个株系100个单株500粒F4籽粒的高分子量麦谷蛋白亚基(HMW—GS)组成，结果表明：1．Glu—D1位点的5 10，5 12的遗传在JY97—1／blosky后代中符合一对相对基因的分离。2．JY97—2／blosky后代HMW—GS组成类型变异极其丰富。在G1u—A1，G1u—B1和G1u—D1三个位点上分别检测到2，9和6种不同的亚基类型，在Glu—A1位点上1亚基和null的频率分别为52．85％和47．15％；Glu—B1位点上的变异最丰富，出现20；7 8 9；6 8等七种新的等位基因类型；Glu—D1位点存在2 5 10；2 12，5 10；5 12等四种新的等位基因类型。最优亚基组合1，7 8，5 10的比例为11．84％。3．两个组合中Glu—B1b或及Glu—B1c的不完全表达率分别为2．07％和1．9％。     

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.     

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