The origin of six-rowed ‘wild’ barley from the western Himalaya

Summary Plants were grown from seed of two-rowed wild barley, Hordeum spontaneum, and six-rowed brittlerachised barley. H. agriocrithon, collected in Ladakh, north-western India. Whereas the H. spontaneum remained true to type, segregation for morphological characters was observed in progeny rows grown from heads of H. agriocrithon plants. The H. agriocrithon heads also showed segregation for a biochemical character, the polypeptide pattern of the endosperm storage protein fraction (hordein). The H. agriocrithon seed therefore originated from natural hybridization between cultivated H. vulgare and weedy H. spontaneum. Crosses of H. vulgare and H. spontaneum gave progeny which resembled H. agriocrithon and showed similar hordein polypeptide segregation patterns. The results indicate that six-rowed brittle-rach ised barleys from the Himalayas have a similar origin to forms found in the Middle East, and that H. agriocrithon does not play a direct role in the evolution of barley.     

辣椒种子贮藏蛋白的含量测定和电泳分析

对12个辣椒品种种子内4种贮藏蛋白清蛋白、球蛋白、醇溶蛋白和谷蛋白进行了含量测定和SDS，PAGE电泳分析。结果表明：辣椒种子贮藏蛋白含量以清蛋白和谷蛋白含量最高，其次是球蛋白，醇溶蛋白的含量最低。品种间蛋白质含量差异不明显。各品种都能通过清蛋白、球蛋白和谷蛋白的蛋白质亚基组成信息区别出其差异性。     

The effect of introgressions of wheat D-genome chromosomes into 'Presto' triticale

Hexaploid triticale (X Triticosecale Wittmack) (2n= 6x= 42, AABBRR) and wheat (Triticum aestivum L.) (2n= 6x= 42, AABBDD) differ in their R and D-genomes. This produces differences in both agronomic and end-use quality characteristics. Our objective was to determine how introgressions of individual chromosomes from the D-genome of wheat affect these characteristics of a winter triticale 'Presto'. We studied the effects of 18 D-genome chromosome substitution lines, 15 sib-lines as controls, and five check cultivars at Lincoln, NE in 1996, using a randomized complete block design with two replications. The experiment was repeated at Lincoln and Mead, NE in 1997 and 1998 with 15 substitution lines that survived the first winter in Lincoln, along with their 12 control sibs and five check cultivars. Few D-genome chromosomes had positive effects. Chromosomes 2D, 4D, and 6D significantly reduced plant height when substituted for 2R, 4B, and 6R, respectively. No grain yield increases were associated with any of the D-genome chromosomes tested, but three substitutions decreased the grain yield. Depending on the allele of the hardness gene present, chromosome 5D increased or decreased kernel hardness when substituted for 5R or 5A, respectively. Introgressions of chromosomes 1D and 6D improved end-use quality characteristics of Presto. These results suggest that apart from beneficial effects of individual loci located on the D-genome chromosomes, no major benefit can be expected from D-genome chromosome substitutions.     

Comparison of the isozyme variation in tall fescue parents and their somaclones

Summary This study was conducted using the isozymes ACP-1, ADH-1, GOT-2, GOT-3, MDH, 6-PGD-1 and PGI-2 to: a) compare isozyme banding patterns of tall fescue somaclones with parents and b) correlate tissue culture-induced chromosome abnormalities with variant banding patterns. The 174 somaclones were grouped into seven categories based on their meiotic analyses and time of regeneration from culture. Differences in isozyme frequency between categories compared by chi-square tests were greatest for MDH, 6-PGD-1 and PGI-2, and least for ACP-1. The most significant differences in frequency were found between somaclones and parents. In comparisons of somaclone categories, the most different isozyme distributions were between the early vs. late regenerated somaclones. No significant differences in isozyme frequencies were found between all 42-chromosome somaclones vs. aneuploid somaclones and the three somaclone groups (42-normal, 42-abnormal, aneuploid) compared to each other. This study suggests that culture-induced isozyme variation alters the distribution of the isozyme phenotypes, but is not directly correlated with chromosome abnormalities.     

Polyacrylamide gel electrophoresis of wheat gliadins: the use of a moving boundary for improved resolution

Summary The process of the separation of gliadin proteins of wheat, using polyacrylamide gel electrophoresis, was studied in detail. It was shown that electrophoresis is a dynamic process during which the pH of the gel changes together with the potassium ion concentration. The most positive effect on the separation of the gliadins was generated by a moving front, which is a boundary between regions with a low concentration of K⁺ ions and a low pH, and region with a high concentration of K⁺ ions and a high pH, after optimization of the concentrations of the cations and anions in the electrode solutions. The finding was exploited for the development of an extremely simple electrophoresis system, in which buffers were not needed for obtaining a high resolution. The system was further improved by applying a stacking gel. The advantages of this system are discussed. This new approach may be useful for improving electrophoresis systems for other applications.     

适用于水稻微粒体蛋白的双向电泳技术及苯达松抗性相关蛋白的初步分析

针对不同来源的样品，建立相应的双向电泳(two-dimensional gel electrophoresis, 2-DE)技术是开展蛋白质组学研究的基础。以野生型水稻(O. sativa L.)农林8号(N8)及其苯达松敏感致死(bentazon sensitive lethal, bsl)突变体农林8号m (N8m)为材料，通过优化条件，建立了适合于水稻微粒体蛋白的双向电泳技术。并通过双向电泳图谱的比对，共找到15个差异蛋白点，分为供试材料间差异、苯达松处理前后差异和N8在苯达松处理后特异表达等3种类型。结合苯达松抗性比较及苯达松残留分析，推测材料间差异是因γ射线辐照引起基因结构变异，从而影响了基因的表达；苯达松处理前后差异与氧自由基清除酶系或系统获得抗性相关酶系有关；N8在苯达松处理后特异表达与苯达松代谢有关。     

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.     

Relationships between different prolamin proteins and some quality properties in durum wheat

The objective of this paper was to study the differences between some prolamin variants coded at the loci Glu-3/Gli-1, Glu-1 and Gli-A2 and their relative roles in durum-wheat quality. F₃ lines from four durum wheat crosses (‘Abadia’בMexicali’. ‘Oscar’בArdente’, ‘Oscar × Mexicali’ and ‘Alaga’בC. of Balazote’) were analysed for gliadin and glutenin composition by electrophoresis. Whole-grain-derived samples were analysed for SDS sedimentation (SDSS) value, mixing properties, and contents of protein and vitreousness. The glutenin patterns LMW-2. LMW-2^? and LMW-2 (CB) at Glu-B3/Gli-B1 were associated with better gluten quality than were LMW-1 and LMW-2*. The glutenin subunits LMW4 and LMW3 + 15 at Glu-A3/Gli-A1 and HMW-1 showed better mixing properties than LMW7 + 12, LMW5 and the null phenotype. respectively. The HMW glutenin subunits 20 + 8 at Glu-B1 showed a negative association with gluten quality, but the rest of the HMW glutenin subunits and α-gliadins did not show any influence on gluten quality. Correlations between the results of the SDSS test and the mixograph were highly significant, but no correlation was found between these results and protein and vitreousness contents. The results are discussed in relation to the development of durum wheat varieties with improved qualities.     

小麦易位系麦醇溶蛋白的电泳分析

本文利用聚丙烯酰胺凝胶电泳(PAGE)技术分析了3个小麦易位系及其亲本的麦醇溶蛋白组分,进一步明确了它们的亲缘关系和遗传组成。