药用野生稻复合体ITS1和ITS2序列变异及其系统进化分析

Phylogenetic Analysis of Oryza officinalis Complex Based on Ribosome ITS1 and ITS2 Sequences

通过PCR扩增并测序分析稻属药用野生稻复合体5个野生稻种基因组完整的ITS区及5.8S区,并与栽培稻ITS序列进行比较,构建分子系统进化树,探讨了稻属药用野生稻复合体内不同种间的亲缘关系和系统进化。结果表明,ITS1和ITS2均有较高的G/C含量,ITS1序列的长度多态性相对较高,ITS2序列的碱基突变频率较高。药用野生稻和高秆野生稻亲缘关系很近,而与栽培稻亲缘关系较远;短药野生稻、斑点野生稻、澳洲野生稻与药用野生稻亲缘关系渐近,处于进化的过渡阶段。

Five wild rice species in the O.officinalis complex and two cultivated rice varieties were phylogenetic analyzed based on the ribosome ITS1 and ITS2 sequences.Their complete ITS and the 5.8S sequences on the ribosome region were amplified by polymerase chain reaction technique and were analyzed by online software CLUSTAL W（2.0.12）Multiple Sequence Alignments and Neighbor Joining.The results showed the ITS sequences all had high G/C contents.By comparison,the ITS1 had relatively high sequence length polymorphism and the ITS2 had more base mutations.O.officinalis and O.alta were clustered together in the phylogenetic tree and they were far from the cultivated rice species.The O.australiensis,O.punctata and O.brachyantha were located between these two clusters and they were on the interim phase of rice evolution.