斑茅割手密复合体杂交利用过程野生特异基因遗传分析

Genetic Analysis of Wild Speci?c Genetic Loci in the Hybridization Process for Intergeneric Hybrid Complex(Erianthus arundinaceus×Saccharum spontaneum)

揭示斑茅割手密复合体在杂交利用过程中的斑茅、割手密野生特异基因在各世代的遗传规律,为利用斑割复合体创制甘蔗育种新亲本提供理论依据。利用AFLP-PCR分子标记结合毛细管电泳技术对斑割复合体在杂交利用过程中的斑茅、割手密野生特异基因在各世代的传递动态进行分析,并研究它们之间的遗传关系。29对AFLP引物组合共扩增出3695个位点,多态性比例为97.89%。斑茅和割手密对斑割复合体的遗传贡献率分别为43.96%和56.04%。斑茅特异位点在F1、BC1和BC2 3个世代的平均遗传率分别为8.25%、1.90%和0.63%,割手密特异位点在F1、BC1和BC2 3个世代的平均遗传率分别为16.98%、2.40%和0.21%,特异遗传物质均呈逐代减少趋势。比较不同世代甘蔗栽培种亲本遗传到后代的特异位点比率,F1的GT02-761特异位点比率最高,BC1的GT05-2743特异位点比例平均高达92.75%,BC2的ROC23遗传率最低,为49.09%,FN39遗传率最高,达94.32%。聚类分析结果表明斑割复合体偏向父本遗传,斑割复合体杂交后代偏向甘蔗栽培种遗传,与分子遗传关系分析结果一致。研究表明,经过3代的遗传重组,斑割复合体后代的遗传物质与斑割复合体相比已发生了很大的改变;研究明确了斑茅、割手密2个亲本在3个世代的遗传贡献规律,为进一步的杂交选育提供理论支持。

The inheritance regularity of wild specific loci for Erianthus arundinaceus(Retz.)Jeswiet and Saccharum spontaneum L. from intergeneric hybrid complex(E. arundinaceus×S. spontaneum)inheriting to generations was investigated,in order to provide theoretical basis for exploring new sugarcane parents. AFLP-PCR molecular markers combined with capillary electrophoresis were used to analyze the transmission dynamics of wild speci?c loci over generations and also clarify the genetic relationship among these materials. A total of 3695 loci were amplified from 29 AFLP primer combinations,with a polymorphic ratio of 97.89%. The genetic fragments derived from E. arundinaceus(Retz.)Jeswiet and S. spontaneum L.were 43.96% and 56.04% respectively. The average heritability of E. arundinaceus(Retz.)Jeswiet in F1,BC1 and BC2 were 8.25%,1.9% and 0.63%,respectively,and the average heritability of S. spontaneum L.in F1,BC1 and BC2 was 16.98%,2.4% and 0.21% respectively. Both indicated a reduction of foreign speci?c genetic loci over generations. By analyzing the ratios of sugarcane speci?c loci that remained in different generations,the genetic information of GT02-761 has been ranked ?rst in F1. The average percentage of special loci for GT05-2743 inheriting to BC1 was 92.75%. The heritability for ROC23 inheriting to BC2 was the lowest,and the heritability for FN39 was the highest,up to 94.32%.The cluster analysis showed that the intergeneric hybrid complex was inherited more from male parent and the progeny from the intergeneric hybrid complex were inherited more from the sugarcane(Saccharum spp.),which was consistent with the analysis of molecular genetic relationship. The results showed that the genetic loci for the hybrids from intergeneric hybrid complex had changed a lot compared with that of intergeneric hybrid complex in the process of genetic recombination for three generations. Thus,this work analyzed the inheritance regularity for two parents inheriting to three generations,and the outcome might provide suggestions for future breeding.