Abstract Pinus sibirica and P. pumila are Asian five-needle pines with vast geographic distributions that are partially overlapping. Natural hybrids with intermediate morphology have been found previously, but there is a lack of evidence of ongoing introgression. The goal of our study was to elucidate the genetic structure of P. sibirica and P. pumila populations growing in the north-east of their sympatry zone (Aldan plateau) using cytoplasmic DNA markers. All studied P. sibirica and P. pumila trees had usual species-specific growth habits. Using nad1 intron2 of mitochondrial DNA (mtDNA) and trnV of chloroplast DNA (cpDNA) we found that trees morphologically identified as P. sibirica had pumila-specific mtDNA. Moreover, some of them also had pumila-specific cpDNA. P. pumila trees were typical and had pumila-type cytoplasmic DNA markers. These results suggest that interspecific hybridization took place long ago and lead to introgression and cryptic hybrids with P. sibirica appearance and P. pumila mtDNA

中文翻译：

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阿尔丹高原（东西伯利亚）西伯利亚松和普米拉松之间的不对称渗入

摘要 西伯利亚松和普米拉松属亚洲五针松，地理分布广，部分重叠。先前已发现具有中间形态的天然杂种，但缺乏正在进行的基因渗入的证据。我们研究的目的是使用细胞质 DNA 标记阐明生长在其交界区（阿尔丹高原）东北部的 P. sibirica 和 P. pumila 种群的遗传结构。所有研究的 P. sibirica 和 P. pumila 树都具有通常的物种特异性生长习性。使用线粒体 DNA (mtDNA) 的 nad1 内含子 2 和叶绿体 DNA (cpDNA) 的 trnV，我们发现形态学上鉴定为 P. sibirica 的树木具有 pumila 特异性 mtDNA。此外，其中一些还具有 pumila 特异性 cpDNA。P. pumila 树是典型的并且具有 pumila 型细胞质 DNA 标记。