Abstract Detail

Pteridology

Patel, Nikisha Rashmi [1], Barrington, David [2].

Apomixis and reticulate evolution in Chinese Polystichum section Xiphopolystichum.

The fern genus Polystichum (Dryopteridaceae) has a cosmopolitan distribution with a center of diversity in Eastern Asia, where species diversity is notably rich in apomictic lineages, most of which are in section Xiphopolystichum. The section, a monophyletic group comprising 34 species with five thus far identified as apomicts, is an ideal study system for understanding the origins and evolutionary significance of apomictic lineages. Asexual lineages are often polyploid and arise by hybridization, and the origins of apomicts in Xiphopolystichum are so far unexplored. The present study samples Polystichum sect. Xiphopolystichum sensu stricto in its entirety across its Western Chinese center of diversity to identify potential progenitors of known apomicts. Cytological analysis with flow cytometry reveals diploid, triploid, and tetraploid cytotypes of five apomicts, Polystichum xiphophyllum, P. mayebarae, P. tsus-simense, P. neolobatum, and P luctuosum. Each cytotype has a unique suite of morphological traits contributing to the extraordinary morphological diversity found across species in Xiphopolystichum. Further, molecular systematics utilizing next-generation sequencing technology for sequencing nuclear markers (gapCp and PgiC) suggests that Xiphopolystichum is a reticulate group including hybrid lineages with multiple origins.

1 - University Of Vermont, 111 Jeffords Hall, 63 Carrigan Drive, Burlington, VT, 05405, USA
2 - University Of Vermont, Jeffords Hall, 63 Carrigan Drive, Burlington, VT, 05405, USA

Keywords:
Apomixis
Systematics
hybridization
polyploidy.

Presentation Type: Oral Paper
Session: 7, Pteridological Section/AFS
Location: 203/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 8:15 AM
Number: 7001
Abstract ID:824
Candidate for Awards:George R. Cooley Award