1BL／1RS易位系对小麦高分子量谷蛋白亚基遗传的影响初析

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

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。

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 Fl 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 Fl 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.