系谱追踪等位变异法分析籼粳交亲本对衍生后代的遗传贡献

Analysis of the Genetic Contribution of the Ancestors to the Offsprings from Indica-Japonica Crosses of Rice by Pedigree Allele Method

利用16个亲本及特异种质92gk729的39个衍生品系为材料,采用221对SSR标记和系谱追踪等位变异法分析祖先亲本在籼粳杂交各衍生世代的遗传贡献。结果表明:(1)在92gk729中有10对SSR引物位点上出现4个祖先亲本杂交重组的特异条带,有5个重组后的特异位点能稳定传递到衍生后代中,有1个重组后的特异位点在亲本及衍生品系中都没有出现;(2)ketan Nangka、嘉南粳、02428、明恢72对92gk729的遗传贡献率分别为15.09%、21.32%、22.78%和34.64%。4个亲本杂交染色体片段重组后能产生新的特异位点,其遗传贡献率是6.17%;(3)4个祖先亲本在每条染色体上对衍生后代遗传贡献的趋势都是随着衍生代数的递增,遗传贡献率逐渐下降。亲本对各世代衍生品系的遗传贡献率为明恢72>02428>嘉南粳>Kenta Nangka;(4)采用系谱追踪等位变异法进行数据分析,然后对数据进行聚类,发现同一杂交组合的品系、同一系谱分支存在衍生关系的大部分品系聚为一类,后代亲缘关系相近的高代材料聚为一类。说明该法能够较好地反映祖先亲本对后代的遗传贡献。

In order to analyze the genetic contribution of the ancestors to the offsprings from rice subspecies cross , 16 parents and 39 varieties derived from special germplasm （92gk729） were analyzed by 221 pairs of SSR primers and pedigree allele method .The results showed that ：（1） In 92gk729 ,the special fragment of the recombination of the four ancestors were amplified with 10 pairs of SSR primers ;5 specific sites of the recombination could stably transmit into the offsprings ;one specific site of the recombination did not appear at the ancestors and the offsprings , so these special fragments need to be further analyzed . （2 ） The genetic contribution ratio of Ketan Nangka , JiaNanJing ,02428 and Minghui72 to 92gk729 was 15.09% ,21.32% ,22.78% and 34.64% , respectively .The hybridization and recombination of the chromosome segment of the four parents amplified new specific sites ,whose genetic contribution rate was 6.17% .（3） On every chromosome ,the trend of the genetic contribution from the four ancestors to the offsprings was gradually decreased ,accompanied with the increase of generations .The genetic contribution from the four ancestors to the offsprings showed Minghui72〉02428〉JiaNanJing〉Kenta Nangka .（4） The cluster analysis of the data gained by the pedigree allele method was performed .The results showed that of the same hybrid combination ,most of the varieties of the same genealogical branch with the derivative relations could be clustered together ;the material of high derivative generations in close sibship of descendant could be clustered＆amp;nbsp;together .We could conclude that pedigree allele method could better reflect the genetic contribution of the ancestors to the offsprings .