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南洋杉科是最原始的松杉纲类群之一,其系统发育关系与起源(分支)时间研究具有极为重要的意义.利用自行测定和Gen Bank中获得的核核糖体18S和26S,叶绿体16S,rbcL,matK和rps4以及线粒体coxⅠ和atp1等8个基因的DNA序列,构建了南洋杉科的分子系统树,确定该科属间系统发育关系应为((瓦勒迈杉属,贝壳杉属),南洋杉属).以瓦勒迈杉属和南洋杉属Araucaria族和Eutacta族的化石记录作为时间标定,估计南洋杉科的起源在(308±53)百万年前,即该科在石炭纪晚期起源,而非以往认为的三叠纪.用相同基因组合还估计出南洋杉属起源于(246±47)百万年前,贝壳杉属起源于(61±15)百万年前.对不同基因所构建的系统树进行统计分析并对它们所估计的起源时间进行比较表明,叶绿体matK和rps4基因较为适合南洋杉科的系统发育与起源时间估计研究.
Araceae is one of the most primitive Lycium species and its phylogenetic relationship is very important for the study of its origin (branching) time.Using self-assay and nuclear ribosomal 18S and 26S obtained from GenBank, chloroplast 16S, rbcL, matK, rps4 and mitochondrial DNA sequences of coxⅠ and atp1 were used to construct the molecular phylogenetic tree of Araceae. The phylogenetic relationship among the genera should be ((Valleria, Kaurigen) , Araucaria) .With the time records of the fossil records of the Willaria and Araucaria and the Eutacta, the origin of the Araucariaceae is estimated at (308 ± 53) million years ago, Late Cretaceous origin, rather than previously considered Triassic. Using the same gene combination also estimated that Araucaria originated (246 ± 47) millions of years ago, the genus Kaempferia originated (61 ± 15) million years ago. Statistical analysis of phylogenetic trees constructed from different genes and comparison of their estimated origins suggest that the chloroplast matK and rps4 genes are more suitable for the phylogeny and origin estimation of Araceae.