S2 Data -

Iron-Heart Cunninghamia lanceolata, a wild relative of Chinese fir with valuable genetic and breeding traits, has been limited in genetic studies due to a lack of genomic resources and markers. In this study, we conducted transcriptome sequencing of Iron-Heart C. lanceolata leaves using Illumina NovaSeq 6000 and performed assembly and analysis. We obtained 45,326,576 clean reads and 115,501 unigenes. Comparative analysis in five functional databases resulted in successful annotation of 26,278 unigenes, with 6,693 unigenes annotated in all databases (5.79% of the total). UniProt and Pfam databases provided annotations for 22,673 and 18,315 unigenes, respectively. Gene Ontology analysis categorized 23,962 unigenes into three categories. KEGG database alignment annotated 10,195 unigenes, classifying them into five categories: metabolism, genetic information, biological systems, cellular processes, and environmental information processing. From the unigenes, we identified 5,645 SSRs, with dinucleotides repeats being the most common (41.47%). We observed variations in repeat numbers and base compositions, with the majority of markers ranging from 12 to 29 bp in length. We randomly selected 200 primer pairs and successfully amplified 15 pairs of polymorphic SSR primers, which effectively distinguished Chinese fir plants of different origins. This study provides insights into the genetic characteristics of Iron-Heart C. lanceolata and offers a foundation for future molecular marker development, breeding programs, genetic diversity analysis, and conservation strategies.

铁心杉木（Iron-Heart Cunninghamia lanceolata）作为栽培杉木（Chinese fir）的野生近缘种，拥有极具科研价值的遗传与育种性状，但因缺乏基因组资源与分子标记，其遗传研究长期受到限制。本研究采用Illumina NovaSeq 6000测序平台对铁心杉木叶片进行转录组测序，并完成序列组装与分析工作，共获得45,326,576条清洁读段（clean reads）以及115,501条单基因序列（unigenes）。通过5个功能数据库的比对分析，成功完成26,278条单基因序列的功能注释，其中6,693条单基因序列可在全部5个数据库中获得注释，占总单基因序列数的5.79%。通用蛋白质知识库（UniProt）与蛋白质家族数据库（Pfam）分别注释了22,673条和18,315条单基因序列。基因本体（Gene Ontology，GO）分析将23,962条单基因序列划分为3大类。京都基因与基因组百科全书（KEGG）比对分析共注释了10,195条单基因序列，并将其划分为5大类：代谢、遗传信息处理、生物系统、细胞过程以及环境信息处理。从单基因序列中，本研究共鉴定出5,645个简单序列重复（Simple Sequence Repeats，SSRs），其中二核苷酸重复最为常见，占比41.47%。研究发现这些标记的重复次数与碱基组成存在差异，多数标记的长度介于12 bp至29 bp之间。本研究随机选取200对引物进行验证，成功扩增出15对具有多态性的SSR引物，可有效区分不同起源的杉木材料。本研究为解析铁心杉木的遗传特征提供了理论依据，同时为后续分子标记开发、育种工作、遗传多样性分析以及种质资源保护策略制定奠定了坚实基础。