Genomic resequencing unravels species differentiation and polyploid origins in the aquatic plant genus Trapa

Authors

Xiangrong Fan, Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China.
Minghao Qu, State Key Laboratory of Plant Diversity and Specialty Crops, Wuhan Botanical Garden, Chinese Academy of Science, Wuhan, Hubei, 430074, China.
Nancy Rybicki, George Mason University, Fairfax, Virginia, 22030, USA.
Lynde L. Dodd, US Army Engineer Research and Development Center, Vicksburg, Mississippi, 39180, USA.
Jie Min, Department of Environmental and Occupational Health, Milken Institute School of Public Health, The George Washington University, Washington, DC, 20052, USA.
Yuanyuan Chen, Horticulture and Conservation Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China.
Lei Gao, State Key Laboratory of Plant Diversity and Specialty Crops, Wuhan Botanical Garden, Chinese Academy of Science, Wuhan, Hubei, 430074, China.

Document Type

Journal Article

Publication Date

9-1-2025

Journal

The Plant journal : for cell and molecular biology

Volume

123

Issue

5

DOI

10.1111/tpj.70463

Keywords

Trapa; domestication bottleneck; genetic diversity; genome resequencing; species differentiation; tetraploid origins

Abstract

Trapa L. is a non-cereal aquatic crop with significant economic and ecological value. However, debates over its classification have caused uncertainties in species differentiation and the mechanisms of polyploid speciation. This study employed whole-genome resequencing together with the fruit morphology of 229 Trapa accessions (153 Asian and 76 North American samples) to elucidate species differentiation and polyploidization events in Trapa. For the species with AA genome and large fruits, clear genetic differentiation was found between two clades with different geographic origins, that is, from the Yangtze River and Amur River basins. The invasive AA species in North America (T. natans) was identified as originating from the Amur River based on genetic and morphological similarities, while all the cultivated accessions were AA species originating from the Yangtze River with severe genetic impoverishment. The separation of the two BB species with small seeds, that is, T. incisa and T. maximowiczii, was strongly supported by both morphological and genetic evidence. For the tetraploids, Asian and North American tetraploids were revealed to have distinct evolutionary origins. Asian allotetraploids (AABB) originated through hybridization between AA diploids from the Yangtze River Basin and BB diploids T. maximowiczii, supported by nuclear and chloroplast evidence. In contrast, the invasive North American tetraploids (T. bispinosa var. iinumai) exhibited an AACC-like genome, suggesting an independent polyploidization involving an unknown "CC" diploid. These findings provide critical insights into Trapa's complex evolutionary history, polyploidizations, and invasive origins, offering a genomic foundation for the conservation and sustainable utilization of the underutilized aquatic crop amid global environmental challenges.

APA Citation

Fan, Xiangrong; Qu, Minghao; Rybicki, Nancy; Dodd, Lynde L.; Min, Jie; Chen, Yuanyuan; and Gao, Lei, "Genomic resequencing unravels species differentiation and polyploid origins in the aquatic plant genus Trapa" (2025). GW Authored Works. Paper 8016.
https://hsrc.himmelfarb.gwu.edu/gwhpubs/8016

Department

School of Medicine and Health Sciences Student Works