植物生态学报 ›› 2022, Vol. 46 ›› Issue (9): 1098-1108.DOI: 10.17521/cjpe.2022.0024

• 研究论文 • 上一篇    下一篇

新疆野苹果种群遗传结构及其环境适应性

张宏祥1,2,*(), 闻志彬1,2, 王茜1   

  1. 1中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室, 乌鲁木齐 830011
    2中国-塔吉克斯坦生物资源保育与利用联合实验室, 新疆抗逆植物基因资源保育与利用重点实验室, 中国科学院新疆生态与地理研究所标本馆, 乌鲁木齐 830011
  • 收稿日期:2022-01-13 接受日期:2022-03-09 出版日期:2022-09-20 发布日期:2022-10-19
  • 通讯作者: 张宏祥
  • 基金资助:
    国家自然科学基金(32170391);国家自然科学基金(31870323);中国科学院青年创新促进会项目(2019428)

Population genetic structure of Malus sieversii and environmental adaptations

ZHANG Hong-Xiang1,2,*(), WEN Zhi-Bin1,2, WANG Qian1   

  1. 1State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Ürümqi 830011, China
    2Sino-Tajikistan Joint Laboratory for Conservation and Utilization of Biological Resources, Xinjiang Key Lab of Conservation and Utilization of Gene Resources, Specimen Museum of Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Ürümqi 830011, China
  • Received:2022-01-13 Accepted:2022-03-09 Online:2022-09-20 Published:2022-10-19
  • Contact: ZHANG Hong-Xiang
  • About author: E-mail: zhanghx561@ms.xjb.ac.cn
  • Supported by:
    National Natural Science Foundation of China(32170391);National Natural Science Foundation of China(31870323);Project of Youth Innovation Promotion Association of Chinese Academy of Sciences(2019428)

摘要:

新疆野苹果(Malus sieversii)属国家二级保护植物, 是栽培苹果的主要祖先之一。它呈片段化残遗分布于亚洲中部干旱区山地。为了探究影响该物种种群遗传变异的主要环境因子及其适应机制, 该研究选取中国新疆伊犁地区、哈萨克斯坦、吉尔吉斯斯坦分布的10个种群为研究对象, 通过SLAF-seq简化基因组测序获取单核苷酸多态性(SNP)数据。利用ADMIXTURE软件和主成分分析对种群遗传结构进行分型; 利用梯度森林分析和冗余分析评估影响种群遗传变异的主要环境因子; 运用潜在因素混合模型来检测新疆野苹果种群适应局部环境的基因组位点。结果显示: 10个种群可以区分出2个遗传谱系; 谱系A主导东部种群, 谱系B主导西部种群, 而中部种群则出现了两个谱系的交汇; 种群空间遗传结构呈现出沿经度方向上的地理替代格局。气温年较差(bio 07)和气温季节性变化(bio 04)是影响新疆野苹果种群等位基因频率变化的两个最重要环境因子。经注释发现15个环境关联基因位点与植物响应干旱、高盐、冷热等非生物胁迫的很多生理过程相关。综上所述, 新疆野苹果对环境适应的主要压力来自气温条件的变化, 生理适应可能是其响应环境胁迫的主要机制。

关键词: 新疆野苹果, 遗传结构, 环境适应性, 地理替代, 生理适应

Abstract:

Aims Malus sieversii, being listed as a national second-class protected plant in China, is recognized as one of the wild ancestors for domesticated apple. It is fragmentally distributed in arid mountains of the Central Asian. Here, we aimed to investigate the main environment variables shaping population genetic variations and the genetic adaptation in response to these environment variables for this species.

Methods We collected ten M. sieversii populations from Yili Prefecture of China, Kazakhstan and Kyrgyzstan. Single nucleotide polymorphism (SNP) dataset was generated by SLAF-seq. Population genetic structure was inferred using the ADMIXTURE software and principal component analysis. Main environment variables shaping population genetic variations were assessed by gradient forest analysis and redundancy analysis. Tests of associated outlier loci with environmental variations were carried out by latent factor mixed models, which was used to access genetic signatures of local adaptation.

Important findings Ten populations were clustered into two lineages. Lineage A dominated eastern populations, while Lineage B mainly distributed in western populations. Two lineages were mixed in central populations, and an obvious pattern of geographical substitute along the longitude direction was found. The most important environment variables that influence the change of allele frequency for M. sieversii populations were temperature annual range (bio 07) and temperature seasonality (bio 04). Fifteen loci having a significant association with environmental variables were successfully annotated. Most of them were genes related to abiotic stress responses and stress-induced physiological adaptations, such as drought, salt and cold. In conclusion, temperature variation is the main factor that drives the adaptation of M. sieversii to environments. Physiological adaptations, as indicated by the above candidate loci, were most likely the main mechanism related to abiotic stress response.

Key words: Malus sieversii, genetic structure, environmental adaptation, geographical substitute, physiological adaptation