Variation of high-molecular-weight glutenin subunits amongst cultivars of Triticum turgidum L. from Portugal

Summary Variation in high-molecular-weight (HMW) glutenin subunit composition amongst 63 varieties of Triticum turgidum L. from Portugal was investigated using SDS-PAGE. A total of thirteen Glu-A1 and Glu-B1 alleles were identified, and three of them were found to be different from those previously described in the literature. A number of the tetraploid wheats examined contained subunits known to have a beneficial effect of the bread-making properties of T.aestivum. Camara, a tetraploid wheat cultivar carrying a 1D/1B chromosomal substitution, is proposed as a bridge for the transfer of Glu-D1 alleles and of other protein fractions controlled by the 1D chromosomes (Gli-D1 locus) from hexaploid to tetraploid wheat.     

Additive and epistatic effects of allelic variation at the high molecular weight glutenin subunit loci in determining the bread-making quality of breeding lines of wheat

Summary The relation has been studied between the high molecular weight glutenin (HMWg) subunit alleles and the bread-making quality of 226 lines of winter wheat (T. aestivum L.), grown in The Netherlands. The lines represented a wide range of genetic backgrounds, and had not been selected for quality, in contrast to the established varieties used by other authors.The variation in HMWg subunit genotypes accounted for about 20% of the total variation in loaf volume among the lines. Most important was the allelic variation at the Glu-D1 locus. The Glu-D1 allele encoding the subunits 5+10 was superior to its allelic counterpart, encoding 2+12. The difference in average of loaf volume between groups of lines containing 5+10 or 2+12 was negatively related with protein content of the flours. When protein content was below 9.2%, no effect of allelic variation at the Glu-D1 locus was present. Epistatic effects between the Glu-I loci also contributed to the variation in loaf volume of the lines: i.e. the effect of allelic variation at Glu-A1 and Glu-B1 depended on the allele present at the Glu-D1. The contribution of the epistatic effects was about half the contribution of the additive effects, and should therefore be included in predictive models for bread-making quality.     

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 high-molecular-weight glutenin subunit composition of Soviet wheat varieties

Summary One hundred and twenty-eight wheat varieties bred in the Soviet Union were screened for the composition of high-molecular-weight (HMW) subunits of glutenin. In general, variability was low compared to that seen in varieties from other countries. However, varieties from different regions showed distinctive patterns, in some cases clearly due to the use of particular parents in certain breeding programmes, but in others possibly due to the adaptive value of particular alleles to the environmental conditions under which the varieties were bred. For example, among spring varieties, the Glu-D1 allele encoding subunits 2+12 was more common in varieties from areas with limited rainfall than was the allele encoding subunits 5+10.The pattern of HMW glutenin subunits amongst varieties with superior bread-making quality showed few differences from that amongst bread-making varieties of lower quality.Abbreviations BMQ bread-making quality - HMW high-molecular-weight - LMW low-molecular-weight - SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis     

Distribution of the wheat–rye translocation 1RS.1BL among bread wheat varieties of Bulgaria

The distribution of the wheat–rye translocation 1RS.1BL was studied in 31 winter wheat varieties from Bulgaria. The presence of the translocation was verified in 17 varieties using chromosome N‐banding analysis, PAGE‐analysis of grain storage proteins and DNA‐marker analysis. The 1RS.1BL has been transmitted in 54% of varieties with a known source of the translocation in their pedigree.     

1BL/1RS易位对小麦贮藏蛋白组分含量和面团流变学特性的影响

利用1BL/1RS易位系后代研究1BL/1RS易位对贮藏蛋白组分含量和面团流变学特性的影响有助于指导小麦品质改良工作。选用师栾02-1/周麦16组合14份F6品系,于2012—2013年度分别种植在河南安阳和焦作,采用反相超高效液相色谱(RP-UPLC)和凝胶排阻超高效液相色谱(SE-UPLC)方法分析贮藏蛋白组分含量,并研究它们与面团流变学特性的关系。结果表明,拉伸仪延展性和最大抗延阻力、不溶性谷蛋白聚合体含量和谷蛋白、醇溶蛋白等贮藏蛋白组分含量及其比例均受1BL/1RS易位有无类别和类内品系效应的显著影响,以类内品系效应较大;拉伸仪拉伸面积、谷蛋白含量及醇溶蛋白与谷蛋白含量比值的类内品系效应显著且较大。易位系和非易位系的贮藏蛋白组分含量和面团流变学特性的相关系数达显著水平,在易位系中,不溶性谷蛋白聚合体含量和拉伸面积(r=0.92,P0.001)、延展性(r=0.92,P0.001)、最大抗延阻力(r=0.80,P0.01)呈显著正相关,面团流变学特性较好的品系不溶性谷蛋白聚合体含量均较高;在非易位系中,醇溶蛋白与谷蛋白含量比值和拉伸面积(r=?0.91,P0.001)、最大抗延阻力(r=?0.88,P0.001)呈显著负相关,面团流变学特性较好的品系醇溶蛋白与谷蛋白含量比值均较低。上述信息对以不溶性谷蛋白聚合体含量和醇溶蛋白与谷蛋白含量比值为指标改良1BL/1RS易位系的面筋品质有重要意义。     

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。     

The effect of chromosome 1AL/1RS translocation on agronomic performance of 85 F2-derived F6 lines from three Triticum aestivum L. crosses

Summary The effect of the 1AL/1RS chromosome translocation on grain yield and other agronomic characteristics of 85 random F₂-derived F₆ bulks from three 1AL 1RS × 1A bread wheat crosses was determined under optimum and reduced irrigation conditions at CIANO, Yaqui Valley, Sonora, Mexico, during the 1991–1992 and 1992–1993 crop production cycles. Harvest plots of 5.0 m² were arranged in an alpha lattice design with three replications. The 1AL/1RS translocation increased grain yield, above-ground biomass, spikes/m², and test weight under both irrigated and dryland conditions. Homozygous chromosome 1A lines, on the other hand, possessed longer spikes with more grains. The 1AL/1RS cultivars had an advantage in 1000-grain weight, which was detected only under optimum irrigation. The translocation lines showed later maturity and longer grainfilling period than the 1A genotypes under one irrigation treatment. A significant relationship between grain yield and test weight was detected only among the 1AL/1RS genotypes, indicating that they possess heavier and plumper grains than the 1A genotypes. These results encourage the continued use of the 1AL/1RS translocation in wheat improvement.     

Agronomic performance of chromosomes 1B and T1BL.1RS near-isolines in the spring bread wheat Seri M82

The T1BL.1RS wheat (Triticum aestivum L.) - rye (Secale cereale L.) translocations have been of particular interest and are widely used in bread wheat breeding programs. The objective of this study was to determine the effect of the T1BL.1RS chromosome on grain yield and its components using 20 near-isolines of spring bread wheat cultivar ‘Seri M82’ (10 homozygous for chromosome 1B substitution and 10 homozygous for T1BL.1RS). The test lines have been produced by substituting the 1B chromosome in Seri M82 (T1BL.1RS, T1BL.1RS) through backrossing. Two field experiments were evaluated under optimum (five irrigations) and reduced (one irrigation) moisture conditions for two consecutive production cycles at the Mexican National Agricultural Research Institute, Ciudad Obregon, Sonora, Mexico. The presence of T1BL.1RS had a significant effect on grain yield, harvest index, grains/m², grains/spike, 1000-grain weight, test weight, flowering date and physiological maturity in both moisture conditions. The agronomic advantage of the 1B substitution lines on above-ground biomass yield at maturity, spikes/m²and grain-filling duration was expressed only under the optimum moisture condition. The presence of T1BL.1RS increased grain yield 1.6% and 11.3% for optimum and reduced moisture conditions, respectively. These results encourage further use of T1BL.1RS wheats in improving agronomic traits, especially for reduced irrigation or rainfed environments. This revised version was published online in August 2006 with corrections to the Cover Date.     

Genetical analysis of contribution of low-molecular-weight glutenin subunits to dough strength in common wheat (Triticum aestivum L.)

To evaluate the effect of low-molecular-weight glutenin subunit (LMW-GS) genes on dough strength, locus-specific primers of LMW-GS genes and gliadin bands tightly linked to LMW-GS genes were analyzed in common wheat. Segregation analysis of the F₂ progeny from a cross between Haruhikari, a good bread-making quality cultivar, and Asakaze-komugi, a poor bread-making quality cultivar, showed that dough strength significantly correlated with one amplified LMW-GS gene located at the Glu-B3 locus from Haruhikari. There was no specific reference to the gliadin bands identified as promising markers in the cross under study. The LMW-GS gene of Haruhikari had a seven amino-acid deletion in the repetitive domain relative to Asakaze-komugi, as well as six amino-acid substitutions, three of which would be expected to cause changes in hydrophilicity. The presence of the LMW-GS gene and other LMW-GS genes tightly linked to it may affect the dough strength of wheat.     

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.     

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.     

1BL/1RS易位对小麦加工品质的影响

分析了138份国内小麦品种和14份国外优质品种的1BL/1RS易位状况和高低分子量麦谷蛋白亚基组成，并将其中的78个品种连续两年在两地种植，研究了1BL/1RS易位对小麦籽粒品质和面条品质的影响。结果表明，1BL/1RS易位品种的优质高、低分子量麦谷蛋白亚基出现频率显著低于非1BL/1RS易位品种；1BL/1RS 易位主要影响面团稳定时间、     

Variation in high molecular weight glutenin subunits in landraces of hexaploid wheat from Afghanistan

Summary Variation for high molecular weight (HMW) glutenin subunits is reported in Afghan hexaploid wheat landraces from different locations in the country ranging in altitude from 395 to 3170 metres. The variation appeared to be independent of the altitude and geographical location of the landraces. Studies of a number of samples from each of five sites revealed that at some sites there was allelic variation at theGlu-A1 andGlu-B1 loci coding from HMW glutenin subunits, but there was no variation at theGlu-D1 locus within and between sites.     

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.     

Bread-making quality and yield performance of 1BL/1RS wheat isogenic lines

Isogenic lines were developed in order to assess the precise effects of the 1BL/1RS translocation on quality characteristics and agronomic traits. Results showed that the translocation has a detrimental effect on sodium dodecyl sulphate sedimentation volume, in any background. Yield was similar between translocated and non-translocated lines; however, lines carrying lBL/1RS showed a significant increase in grain weight, together with a decrease in spike number per plant.     

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 subunit composition of Chinese bread wheats

Summary The endosperm storage proteins of 205 Chinese bread wheat cultivars and advanced lines were fractionated by SDS-PAGE to determine their high molecular weight (HMW) glutenin subunit composition. Seventeen alleles were identified: three at Glu-A1, eight at Glu-B1, and six at Glu-D1. The most common alleles were Null, 1, 7+8, 7+9, and 2+12. The results indicate that wheats from different regions differ in their frequencies of HMW glutenin subunits, however, none of the subunits could be related to specific environments. The glutenin quality scores of Chinese wheats ranged from 3 to 10, with an average of 6.7. Increasing quality scores have implications in improving steam-bread making quality for Chinese consumers. On the basis of HMW glutenin subunit composition, Chinese wheats are close to European wheats, especially Italian wheats because several Italian introductions are widely distributed in the pedigrees of Chinese wheat.     

Effects of homoeologous group 1 and 6 chromosomes of the Cappelle-Desprez (Bezostaya 1) substitution lines on aspects of bread-making quality of wheat

Summary The group 1 and 6 inter-varietal chromosome substitution lines of Cappelle-Desprez (Bezostaya 1) were intercrossed along with the donor and recipient varieties, Cappelle-Desprez and Bezostaya 1, to give 36 genetically different families. The analysis of the means of these families showed that variation in SDS-sedimentation volume fitted a predominantly additive model. There were no significant within or between chromosome interactions among the group 1 and 6 chromosomes. Nor was there any evidence for interactions between these chromosomes and those of the background. Significant dominance/within chromosome interactions amongst the background chromosomes were however detected. Some of the positive effects on SDS-sedimentation were associated with increased grain hardness. Chromosome effects on % grain protein were not correlated with SDS-sedimentation.     

A comparison of methods for identifying and surveying the presence of 1BL.1RS translocations in bread wheat

Summary Four methods for detecting 1BL. 1RS translocations in bread wheat have been compared winter wheat cultivars: N-banding of mitotic metaphase chromosomes, sodium lactate electrophoresis at pH 3.1, sodium dodecyl sulphate-polyacrylamide gel electrophorests under conditions, and a recently characterised protein, subtilisin inhibitor, separated by isoelectric N-banding was much the most labour intensive method, and, of the three electrophoretic recommend the use of subtilisin inhibitor, which is at least as easy to interpret as the other is often faster for screening purposes. The sources of the 1BL. 1RS translocation in this matenal Avrora. Kavkaz and Skorospelka 35, which have been extensively used as parents in breeding programmes. Out of 59 cultivars that include a line carrying the 1BL. 1RS pedigree. 23 of them did not carry the translocation; thus the effect on plant phenotype of insufficient to guarantee its selection during breeding.