甘蔗与河八王杂交后代染色体传递及河八王血缘在后代中的遗传

Genetic Analysis of the Hybrid Progeny of S. officinarum L. and Narenga porphyrocoma(Hance) Bor

为探明甘蔗野生基因在杂交过程中的遗传情况,提高甘蔗野生种质资源的利用效率,本研究利用染色体计数法及AFLP结合荧光毛细管电泳技术,开展了甘蔗与河八王杂交的染色体传递和亲本特异位点在杂交种中的遗传分析。结果表明,甘蔗×河八王组合的F1染色体传递行为有n+n和n+2n方式,BC1是n+n方式;利用AFLP标记结合毛细管电泳技术开展了河八王野生基因在F1、BC1后代中的遗传分析,并利用24对AFLP引物组合对4个河八王F1后代、9个BC1后代及其双亲进行了扩增,共检测到总条带数1 774条,其中多态性条带1 690条,多态性检出率为95.26%,各引物组合多态性变幅为87.04%～100%。进一步分析表明,母本桂糖05-3256的特异位点传递给F1后代的比例是63.92%～71.65%,父本广西河八王1特异位点传递给F1后代的比例是8.66%～12.85%。母本崖城94-46特异位点传递给BC1后代的比例是35.19%～48.50%,父本T6-3特异位点传递给BC1后代的比例是33.97%～59.33%;广西河八王1特异位点传递到BC1后代时,比例仅为1.12%～3.35%。另外,F1、BC1的特异位点保持了较高水平。本研究说明了河八王作为父本进行杂交利用过程中,其野生基因在后代中丢失严重,在BC1已处于很低水平,建议前期将河八王作为母本杂交利用,可能会聚合更多有益的河八王野生血缘,从而改良甘蔗的抗逆性。

In order to find out the inheritance of wild genes in sugarcane during hybridization and improve the utilization efficiency of wild sugarcane germplasm resources, genetic analysis of chromosome transmission and parent specific loci in hybrid between sugarcane and Narenga porphyrocoma were carried out by using chromosome counting and AFLP combined with fluorescence capillary electrophoresis technology. The results showed that thechromosomal transfer models were "n +n" and "n +2n" in F1 generation of Sugarcane ×Narenga porphyrocoma combination, and "n +n" mode in BC1population;24 pairs of AFLP primer combinations were used for amplification for 4 individuals of F1 generation, 9 individuals of BC1 generation and their parents. A total of 1 774 bands were detected, of which 1 690 were polymorphic and the polymorphic rate was 95.26%. The polymorphism of each primer combination ranged from 87.04% to 100%. Further analysis showed that the proportion of the specific loci transferred from the maternal parent GT05-3256 to individuals in F1 generation ranged from 63.92%to 71.65%, and the ratio of the specific loci transferred from the paternal parent GXN1(Narenga porphyrocoma) to individuals in F1 generation ranged from 8.66% to 12.85%. The proportion of specific loci transferred from the maternal parental YC94-46 to individuals in BC1 generation ranged from 35.19% to 48.50%, and the proportion of specific loci transferred from the paternal parent T6-3 to individuals in BC1 generation ranged from 33.97% to59.33%. The ratio of specific loci in GXN1 inherited to individuals in BC1 population, the ratio ranged from 1.12%to 3.35% only. In addition, the specific loci of F1 and BC1remained relatively high. This study showed that the wild genes of Narenga porphyrocoma were seriously lost in the offspring and were at a very low level in BC1 generation during the process of crossbreeding which used Narenga porphyrocoma as the male parent. It is suggested that the crossbreeding of Narenga porphyrocoma as female parent in the early stage might gather more beneficial wild blood relationship, and might improve the stress resistance of sugarcane.