High-Molecular-Weight Glutenin Subunit Composition of Chinese Wheat Germplasm

The objective of the present study was to characterize the high molecular glutenin subunits （HMW-GS） composition and the presence of 1B/1R translocation in newly developed wheat （Triticum aestivum L.） germplasm, which have one or more traits that are useful in wheat improvement. Sodium dodecyl sulphate polyacrylamide-gel electrophoresis （SDS-PAGE） and acid polyacrylamide-gel electrophoresis （A-PAGE） were used to detect HMW-GS composition and the presence of 1B/1R wheat-rye （Secale cereale L.） chromosome translocation in the wheat germplasm. Bread-making quality scores of these lines were determined. A high level of variations in HMW-GS encoded by Glu-1 locus was observed. Sixteen major HMW-GS, with 30 combinations, were detected. The percentage of cultivars with more than two desirable subunits was 38.7%. Thirteen cultivars had bread-making quality scores of 10 in combination with one or two desirable agronomical traits, such as high-yield potential, dwarfing stem, resistance to diseases, and/or tolerance to abiotic stress. Sixty-eight （36.6%） cultivars possessed 1B/1R translocation. The newly developed germplasm with HMW-GS for good quality can be promising resources for improving bread-making quality of wheat.

30余年来北部冬麦区小麦品种产量改良遗传进展

采用1965年以来北部冬麦区育成的10个主栽品种,在水、肥供应充足、病、虫、倒伏得到有效控制条件下,连续两年共进行4个点次试验;同时对1B/1R易位系和矮秆基因进行分子鉴定。结果表明,品种产量年遗传进展为64.63 kghm-2或1.20%,其较大幅度的提高出现在1980年丰抗号品种育成时期。丰抗2号和丰抗8号是该地区最早育成的含有1B/1R染色体和Rht-D1 b矮秆基因的品种。主要农艺性状演变的总趋势是抽穗期提前、株高显著降低、生物学产量基本保持稳定、单位面积穗数减少、每穗粒数有所增加、千粒重和收获指数大幅度提高,其年遗传进展分别为-0.10%、-0.70%、0.35%、-0.50%、0.63%、1.12%和0.79%。通过减少不孕小穗和小花数来增加每穗粒数,通过提高灌浆速率来提高千粒重,再把高穗粒重与较多的单位面积穗数结合在一起,是北部冬麦区进一步提高产量的重要途径。

Secalin蛋白检测及其与面团黏性关系的研究

用SDS-PAGE检测了70个小麦品种是否带有黑麦Secalin蛋白,并测试了它们的面团黏性,用PCR检测了部分品种是否含有1RS染色体片断,结果表明:70%的品种为1B/1R易位系;有54.3%的品种面团发黏;带有黑麦Secalin蛋白的品种约有72.5%面团发黏,而不带有黑麦Secalin蛋白的品种只有30%面团发黏;影响面团黏性的主要因素为来源于黑麦的Secalin蛋白;PCR扩增结果表明,在我国存在不带有Sec-1基因的1B/1R小片断易位系。