1BL/1RS易位系对小麦高分子量谷蛋白亚基遗传的影响初析

以1BL/1RS易位系小麦川农18(1, 7+9, 2+12)分别作母本和父本与川农19(N, 7+8, 2+12)杂交, 统计正反交F₂单株后代中1BL/1RS易位染色体所占的比例及HMW-GS的遗传规律, 研究了1BL/1RS易位染色体对HMW-GS遗传的影响。结果表明, 1BL/1RS易位染色体在雌配子和雄配子中都不能完全传递至后代, 且雄配子的传递率低于雌配子。HMW-GS在正、反交F₁中呈共显性遗传。在F₂中, Glu-A1位点上亚基的分离正常; 而Glu-B1位点上亚基的分离以及Glu-A1与Glu-B1位点之间的组合都与理论值不符。在川农19×川农18杂交F1中发现了一粒变异, 其HMW-GS组成为(1, 7+8, x+9, 2+12)。分别检测了其F₂代HMW-GS和醇溶蛋白的组成, 并用SSR分子标记分析了F₁变异和非变异株, 结果证实该变异粒确系两个亲本的杂交后代, 变异的亚基在SDS-PAGE电泳图上位于1Dx5和1Bx7亚基之间, 迁移率与1Bx6相似。

Primary Study on HMW-GS Inheritance Affected by 1BL/1RS Translocation

The common wheat (Triticum aestivum L.) Chuannong 18 with 1BL/1RS translocation chromosome, whose HMW-GS components is (1, 7+9, 2+12) as male and female parent respectively was crossed with Chuannong 19 (N, 7+8, 2+12). Both the female and male gametes of their F₂ progenies showed significantly (P<0.01) lower rate of 1BL/1RS translocation compared with the theoretical value (75%), in which female gamete (65.1%) had higher rate than male gamete (52.4%). In both crosses, HMW-GS subunits (encoded by Glu-A1 and Glu-B1) of parents were all transmitted to F₁ progenies as dominant trait, but deviated the Mendel’s segregation ratios at Glu-B1 and the combination of Glu-A1 &; Glu-B1 loci in F₂ progenies. We also found and confirmed a variant seed in F₁ of Chuannong 19 × Chuannong 18 by detecting its genome DNA with 33 pairs of specific SSR markers and the components of HMW-GS and gliadin of its F₂ progeny. The HMW-GS patterns of the variant seed were (1, 7+8, x+9, 2+12). The band of variant subunit was similar to 1Bx6 by SDS-PAGE analysis, which was between 1Dx5 and 1Bx7.