Abstract Detail

Germinating Ideas - Lightning Talks

Vizzerra, Andrew [1], Baniaga, Anthony [2], Barker, Michael S. [3].

Exploring the distinct impacts of hybridization and polyploidy on genome evolution in homoploid and allopolyploid taxa of Selaginella arizonica ✕ S. eremophila.

Hybridization and polyploidization are common evolutionary processes in vascular plants. Both processes contribute to the evolution of allopolyploid species, but the unique contributions of hybridization versus polyploidy to these species is not clear. This is partly due to the absence of homoploid hybrid species and allopolyploid species from the same parental diploids. Here, we use a unique species complex in Selaginella to explore the impacts of hybridization and polyploidization on genome evolution. Selaginella is one of the largest genera of lycophytes, despite having one of the smallest nuclear genomes found in vascular plants. The southwestern US and mainland Mexico are a center of functional and taxonomic diversity in Selaginella. Here, in the transition zone between the Lower Colorado River valley and Arizona Upland subdivisions, diploid hybrids and allopolyploids of S. arizonica ʉϥ S. eremophila thrive. Both hybrid taxa have distinct levels of desiccation tolerance and occupy more extreme environments than either of the parents. Our current work aims to provide evidence for both types of hybrid species produced from the hybridization of Selaginella arizonica and S. eremophila. Using a combination of transcriptome and genome data, we assembled and annotated five reference Selaginella genomes, including the two hybrid taxa. We aim to investigate the relative contributions of each parent to the genomes of the hybrids and compare the impact of hybridization and polyploidy on genome evolution. These results have the potential for broader implications in our understanding of both ecological and evolutionary genetic processes that govern diploid and polyploid species. Furthermore, this work also provides the potential for a new study system in understanding plant evolution.

1 - University Of Arizona, Ecology And Evolutionary Biology, PO Box 210088, Tucson, AZ, 85721, United States
2 - Yale University, Ecology & Evolutionary Biology, 165 Prospect Street, New Haven, CT, 06511, United States
3 - University Of Arizona, Department Of Ecology & Evolutionary Biology, P.O. Box 210088, Tucson, AZ, 85721, United States

Keywords:
hybridization
polyploidy
Allopolyploidy
selaginella.

Presentation Type: Germinating Ideas Lightning Talk
Session: LT3, Germinating Ideas - Lightning Talks II
Location: Virtual/Virtual
Date: Friday, July 23rd, 2021
Time: 2:00 PM(EDT)
Number: LT3007
Abstract ID:942
Candidate for Awards:None