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101.
102.
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
103.
The storage protein profiles of the seeds of two IITA cowpea cultivars (‘IT84E–124’ and ‘Vita 7’) exposed to three mutagens—sodium azide (NaN3), ethyl methane sulphonate (EMS) and 60Co gamma rays—and those of 18 selected M3 lines were investigated by sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE). The total seed protein, globulin and albumin fractions showed differences in number and intensity of subunit bands, but the least differences were found in the albumin fraction. Both high and low molecular weight bands were observed, the highest being 94.5 kDa and the lowest 12.0 kDa.‘Vita T showed less variability compared with ‘IT84E–124’, as indicated by the relative similarity indices (S.I.) of the two cultivars. The lowest S.I. of 0.200 was found among ‘IT84E–124’ lines while the lowest S.I. among ‘Vita T lines was 0.4706. A number of lines with particular traits were found to be characterized by the presence of specific polypeptide bands. This study demonstrates that induced mutation could create additional variability to supplement existing germplasm and that SDS-PAGE is a useful tool for discriminating and estimating genetic similarities among selections. 相似文献
104.
Eva Johansson 《Euphytica》2002,126(1):143-149
Variation in falling number, amylase activities, protein concentration and composition were investigated in two wheat cultivars
grown in Sweden over two seasons, in four locations, with four N fertilizer rates, with and without fungicide treatment. The
results showed that;
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
• | Tarso had higher falling number, amylase activities, protein concentration and amount of most protein components compared to Kosack. |
• | The environment (year, location, N rate and fungicide treatment) influenced falling number, alpha amylase activities, and protein concentration and composition. |
• | Two processes were related to low falling numbers; late maturity leading to poor starch and protein quality and excessive rains leading to break-down of starch and proteins. |
• | Poor starch and protein properties influenced the bread-making quality to a higher extent than break-down of starch and proteins. |
105.
Summary Methods developed to identify genetically diverse varieties of beans (Phaseolus vulgaris L.) were applied to closely related lines that were difficult to distinguish on the basis of seed morphology. Seedling tissues and seeds of black beans, were examined electrophoretically for isoenzyme and cotyledon proteinn protein patterns. Seven enzymes, extracted from seeds or from seedling stem, root or leaf tissues, were compared for polymorphism. Peptidase, polyphenol oxidase, phosphoglucoisomerase and glutamate oxaloacetate transaminase patterns were the same for all lines. Some differences were observed for acid phosphatase, peroxidase and esterase patterns, but complete discrimination of the six selected lines was not possible on the basis of isoenzyme patterns alone. Using polyacrylamide gel electrophoresis (PAGE) of dissociated 0.1 M acetic acid soluble proteins at pH 3.1 (acid-PAGE), or sodium dodecyl sulphate PAGE (SDS-PAGE) of residual protein extracts, all but one pair of samples in each case could be distinguished from the other samples. Using both techniques all of the lines could be identified unequivocally. 相似文献
106.
Sexual plant reproduction is a complex process that involves a series of interactions between the male gametophyte and the
different cell types of the pistil. These interactions are believed to direct the pollen tube growth until its final target,
the embryo sac. Arabinogalactan proteins are complex proteoglycans that are believed to be involved in these processes. The
pistil is enriched in these highly glycosylated proteins and we provide results that show the selective presence of different
AGP epitopes at the surface of the cells or in the ECM of the tissues that correspond exactly to the pollen tube growth pathway
in Amaranthus hypochondriacus and Actinidia deliciosa. We also show that in Actinidia deliciosa, which is a dioecious plant
with the male flowers having rudimentary ovaries where fertilization does not occur, there is no presence at all of the epitopes
recognised by the monoclonal antibodies utilized in this study.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
107.
为了完善烟草花叶病的预警防控体系,分析烟草感染烟草普通花叶病毒后的蛋白质组早期变化,筛选烟草的早期响应蛋白。[方法]采用iTRAQ技术分析了蛋白质组变化,采用qPCR技术检测基因的表达。[结果]蛋白质组分析发现160个差异表达蛋白质,包括有64个上调表达蛋白和96个下调表达蛋白,这些差异表达蛋白质主要与氧化还原平衡调节、RNA降解、叶绿体组成及光合作用、逆境胁迫响应有关;qPCR结果显示这些差异蛋白质的mRNA表达变化趋势与iTRAQ数据基本一致;及时施用抗病毒药剂(氨基寡糖素和吗胍.乙酸铜)和植物诱抗剂(盐酸吗啉胍和氮苷吗啉胍)能够预防和控制烟草花叶病的发生,但同时发现PR10、LHCB、POD、HSP90、14-3-3和AGO1等蛋白的表达也受到了影响。[结论]试验筛选出一些TMV感染相关的烟草早期响应蛋白,不仅有助于阐述烟草花叶病发生的机制,也可用于筛选新的抗病毒药剂和植物诱抗剂。 相似文献
108.
杏仁蛋白质的提取及功能特性研究进展 总被引:1,自引:0,他引:1
杏仁蛋白是一种理想的植物蛋白,概述了目前杏仁蛋白质的提取方法,综述了国内外蛋白质功能特性的研究。 相似文献
109.
110.
乳蛋白生物活性肽的来源及其生理重要性 总被引:3,自引:0,他引:3
乳蛋白经酶解产生的肽类除了具有营养作用外,还具有多种生物活性,包括阿片肽、阿片拮抗肽活性及免疫调节、抗高血压、抗血栓、抗菌、促进矿质元素吸收等活性.综述了这些活性肽在体内、体外及通过微生物作用的产生情况,并对其生理重要性进行了简要论述. 相似文献