摘要
The angiosperm family Elaeagnaceae comprises three genera and ca.100 species distributed mainly in Eurasia and North America.Little family-wide phylogenetic and biogeographic research on Elaeagnaceae has been conducted,limiting the application and preservation of natural genetic resources.Here,we reconstructed a strongly supported phylogenetic framework of Elaeagnaceae to better understand interand intrageneric relationships,as well as the origin and biogeographical history of the family.For this purpose,we used both nuclear and plastid sequences from Hyb-Seq and genome skimming approaches to reconstruct a well-supported phylogeny and,along with current distributional data,infer historical biogeographical processes.Our phylogenetic analyses of both nuclear and plastid data strongly support the monophyly of Elaeagnaceae and each of the three genera.Elaeagnus was resolved as sister to the well-supported clade of Hippophae and Shepherdia.The intrageneric relationships of Elaeagnus and Hippophae were also well resolved.High levels of nuclear gene tree conflict and cytonuclear discordance were detected within Elaeagnus,and our analyses suggest putative ancient and recent hybridization.We inferred that Elaeagnaceae originated at ca.90.48 Ma(95%CI?89.91e91.05 Ma),and long-distance dispersal likely played a major role in shaping its intercontinentally disjunct distribution.This work presents the most comprehensive phylogenetic framework for Elaeagnaceae to date,offers new insights into previously unresolved relationships in Elaeagnus,and provides a foundation for further studies on classification,evolution,biogeography,and conservation of Elaeagnaceae.
基金
supported by the National Natural Science Foundation of China,Key International(regional)Cooperative Research Project(no.31720103903)
the Science and Technology Basic Resources Investigation Program of China(no.2019FY100900)
the Strategic Priority Research Program of Chinese Academy of Sciences(no.XDB31000000)
the National Natural Science Foundation of China(no.31270274)
the Yunling International High-end Experts Program of Yunnan Province,China(no.YNQR-GDWG-2017-002 and no.YNQR-GDWG-2018-012)
the China Scholarship Council(202004910775)
the Chinese Academy of Sciences(CAS)President's International Fellowship Initiative(no.2020PB0009)
the China Postdoctoral Science Foundation(CPSF)
the United States Department of Energy(grant no.DESC0018247 to PSS,RPG,and DES).
