Translator Disclaimer
17 August 2017 Genome differentiation, natural hybridisation and taxonomic relationships among Eleocharis viridans, E. niederleinii and E. ramboana (Cyperaceae)
Author Affiliations +
Abstract

The role of natural hybridisation and genome changes in the differentiation and speciation of Eleocharis (Cyperaceae) was addressed through the study of the following three closely related species of the polyphyletic series Tenuissimae: Eleocharis viridans Kük. ex Osten, E. ramboana R.Trevis & Boldrini and E. niederleinii Boech., which often reproduce asexually. Molecular and cytogenetic data were used to understand the genomic and karyotypic relationships in the group. Genomes were compared using internal transcribed spacer–cleaved amplified polymorphic sequence (ITS-CAPS) marker and confirmed with random amplified polymorphic DNA, which allowed identification of different genetic groups, with clear evidence of natural hybrids. Karyotype analysis showed numerical variation from 2n = 20–42, with occurrence of chromosome heteromorphisms and polymorphisms, including variability in 35S rDNA site numbers. Meiotic studies demonstrated irregular pairing in some samples, which is associated with hybridisation and asexual reproduction. Genomic in situ hybridisation (GISH) reactions were conducted using two well defined genetic groups as probes, with 2n = 20 and normal meiosis. Probes were tested against each one of the genetic groups and showed positive, partial and negative GISH results, which supported the molecular analysis data. The results indicated that the three studied species are undergoing an intense process of genomic and karyotypic re-arrangement, which results in overlapping of morphological and genomic characteristics. The present study has exemplified the value of an integrative taxonomic approach to solve conflicts in species delimitation in groups undergoing hybridisation.

© CSIRO 2017
Carlos Roberto Maximiano da Silva, Thaíssa Boldieri de Souza, Rafael Trevisan, María Socorro González-Elizondo, José Marcelo Domingues Torezan, Rogério Fernandes de Souza, and André Luís Laforga Vanzela "Genome differentiation, natural hybridisation and taxonomic relationships among Eleocharis viridans, E. niederleinii and E. ramboana (Cyperaceae)," Australian Systematic Botany 30(2), 183-195, (17 August 2017). https://doi.org/10.1071/SB17002
Received: 5 January 2017; Accepted: 1 May 2017; Published: 17 August 2017
JOURNAL ARTICLE
13 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top