Data from: Whole-chloroplast analysis as an approach for fine-tuning the preservation of a highly charismatic but critically endangered species, Wollemia nobilis (Araucariaceae)

The critically endangered Wollemia nobilis W.G. Jones, K.D. Hill & J.M. Allen is endemic to Wollemi National Park north of Sydney (Australia). All known wild individuals are restricted to four sites in a single canyon system. W. nobilis can reproduce sexually but at all sites individual clumps can be multi-stemmed from a common base. In the first genetic study of this species, no genetic variation was found across multiple genetic marker types representing hundreds of nuclear loci, indicating this species is characterised by very low genetic variation. In this study we searched for variation across the chloroplast using shotgun sequencing, bioinformatic extraction of chloroplast DNA and variant detection. Six chloroplast single nucleotide polymorphisms were detected, producing three chlorotypes. Chlorotype 1 is found in every individual surveyed at Sites 1 and 3, and in individuals from Sites 2 and 4. Chlorotype 2 – the most distinct chlorotype – was found in two individuals from Site 4. Chlorotype 3 consists of a single difference from Chlorotype 1 and may represent a somaclonal mutant. These findings will guide management and translocation of this critically endangered species. This study provides a practical template that is highly informative and easily applicable to other taxa in similar circumstances.

极危物种瓦勒迈杉（Wollemia nobilis W.G. Jones, K.D. Hill & J.M. Allen）为澳大利亚悉尼北部沃勒迈国家公园（Wollemi National Park）的特有物种。目前已知的所有野生个体均局限于单一峡谷系统内的4个分布点。该物种可进行有性繁殖，但在所有分布点中，单个丛生株均可由共同基部萌发出多个茎干。在针对该物种的首次遗传学研究中，针对覆盖数百个核基因座的多种遗传标记类型开展检测，未发现任何遗传变异，表明该物种的遗传多样性极低。本研究通过鸟枪测序（shotgun sequencing）、生物信息学方法提取叶绿体DNA并进行变异检测，对该物种的叶绿体基因组变异进行了筛查。研究共检测到6个叶绿体单核苷酸多态性位点，由此划分出3种叶绿体型（chlorotype）。叶绿体型1存在于分布点1和3的全部被检测个体，以及分布点2和4的个体中。叶绿体型2——即分化程度最高的叶绿体型——仅在分布点4的2个个体中被发现。叶绿体型3与叶绿体型1仅存在1个位点差异，推测其可能为体细胞无性系突变体（somaclonal mutant）。本研究结果将为该极危物种的保护管理与迁地保护工作提供指导。此外，本研究构建了一套兼具高参考价值与普适性的实用研究范式，可便捷应用于其他处于类似濒危境遇的生物类群。