【摘要】 为克服产量高、适应性广的中籼组合协优57的直链淀粉含量较高、蒸煮食味品质较差的缺点,对其父母本较高的直链淀粉含量特性进行了改良。先前利用PCR-AccⅠ分子标记辅助选择对其父本057进行改良,育成了直链淀粉含量改良型057,简称057(TT)。本研究以ND42为优质基因的供体,利用PCR-AccⅠ分子标记对协青早B[母本协青早A的保持系,简称协青早B(GG)]进行改良,得到直链淀粉含量改良型协青早B,简称协青早B(TT)。然后用改良前、后的各亲本分别配组,分析各组合的基因型(GG、GT、TT)和食味品质。结果表明,改良单亲的GT型组合协青早B(GG)/057(TT)、协青早B(TT)/057(GG)杂交稻米的直链淀粉含量由原组合协青早B(GG)/057(GG)的26.1%分别降到19.3%和19.2%,但均一性较差。改良双亲的TT纯合型组合协青早B(TT)/057(TT)的杂交稻米,不仅直链淀粉含量降到中等偏低水平(12.5%)、胶稠度变得更软,而且直链淀粉含量的均一性也有了很大的提高。更多还原

【Abstract】 To lower the high amylose content of hybrid rice Xieyou 57(Xieqingzao A/057),Xieqingzao B(the maintainer line of Xieqingzao A)was used as recurrent parent and crossed with a donor parent with low amylose content.PCR-Acc Ⅰ molecular marker was applied during backcross to identify three Wx genotypes,i.e.GG,GT and TT.Then the genotypes,the amylose contents and agronomic traits of the four combinations,Xieqingzao B(GG)/057(GG),Xieqingzao B(GG)/057(TT),Xieqingzao B(TT)/057(GG),Xieqingzao B(TT)/057(TT)were detected,respectively.The amylose contents of the hybrids with heterozygous GT-Wx,i.e.Xieqingzao B(GG)/057(TT)and Xieqingzao B(TT)/057(GG)is 19.3% and 19.2% respectively,lower than that of Xieqingzao B(GG)/057(GG)(26.1%).The amylose contents of different seeds in the two hybrids with heterozygous GT-Wx differed greatly.The combination of Xieqingzao B(TT)/057(TT)with homozygous TT-Wx not only showed a decreased amylose content(12.5%)accompanied by increased gel consistency,but also had an improved uniformity in amylose contents among different seeds.更多还原