Skip Navigation



Journal of Heredity Advance Access published online on February 17, 2006
Journal of Heredity, doi:10.1093/jhered/esj021
This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
97/2/171    most recent
esj021v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Aguin-Pombo, D.
Right arrow Articles by Freitas, N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Aguin-Pombo, D.
Right arrow Articles by Freitas, N.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The American Genetic Association. 2006. All rights reserved. For permissions, please email: journals.permissions@oxfordjournals.org.
Received June 13, 2005
Accepted December 23, 2005

Article

Multiple Parthenoforms of Empoasca Leafhoppers from Madeira Island: Where Are These Unisexual Forms Coming From?

Dora Aguin-Pombo 1 *, Valentina Kuznetsova 2, and Nelio Freitas 3

1 From the Department of Biology, University of Madeira, Campus da Penteada, 9000-390 Funchal, Madeira, Portugal; CEM, Centre for Macaronesian Studies, University of Madeira, Campus da Penteada, 9000-390 Funchal, Madeira, Portugal
2 From the Department of Karyosystematics, Zoological Institute, Russian Academy of Sciences, 199034 St. Petersburg, Russia
3 From the Department of Biology, University of Madeira, Campus da Penteada, 9000-390 Funchal, Madeira, Portugal

* To whom correspondence should be addressed.
Dora Aguin-Pombo, E-mail: aguin{at}uma.pt


  Abstract

There are controversial opinions on whether asexual reproduction is more common on islands than on the mainland. Although some authors consider that the evidences of geographical parthenogenesis support the view that asexual reproduction is more common on islands, comparative data on the modes of reproduction of insular and continental taxa confirming this statement are very limited. In this work, we report the presence of three unisexual forms and three bisexual species of the genus Empoasca (Cicadelloidea, Hemiptera, Insecta) from Madeira Island. Experimentally, the unisexual forms reproduced in the absence of males for several generations. The chromosome analysis has shown that the bisexual species differ from one another in chromosome number, and unisexual forms are apomictic and also each have different chromosome numbers. Of parthenoforms, one is triploid and two are of obscure level of ploidy, 2n or 3n. The results obtained show that for this genus unisexual forms are more common on Madeira Island than in the nearby continental areas. It is suggested that unisexual forms may be more plentiful on islands than on the mainland because if an asexual reproduction event occurs, the relaxing competition in these underexploited and enemy-free habitats may favor the establishment of new parthenogenetic lineages.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.