Genomic effects of population collapse in a critically endangered ironwood tree Ostrya rehderiana

作者：Yongzhi Yang, Tao Ma, Zefu Wang, Zhiqiang Lu, Ying Li, Chengxin Fu, Xiaoyong Chen, Mingshui Zhao, Matthew S. Olson, Jianquan Liu · 发表于：Nature Communications · 年份：2018 · DOI：10.1038/s41467-018-07913-4 · 被引用次数：140 · 研究领域：Genetic diversity and population structure、Genomics and Phylogenetic Studies、Ecology and Vegetation Dynamics Studies

Increased human activity and climate change are driving numerous tree species to endangered status, and in the worst cases extinction. Here we examine the genomic signatures of the critically endangered ironwood tree Ostrya rehderiana and its widespread congener O. chinensis. Both species have similar demographic histories prior to the Last Glacial Maximum (LGM); however, the effective population size of O. rehderiana continued to decrease through the last 10,000 years, whereas O. chinensis recovered to Pre-LGM numbers. O. rehderiana accumulated more deleterious mutations, but purged more severely deleterious recessive variations than in O. chinensis. This purging and the gradually reduced inbreeding depression together may have mitigated extinction and contributed to the possible future survival of the outcrossing O. rehderiana. Our findings provide critical insights into the evolutionary history of population collapse and the potential for future recovery of the endangered trees.