These authors contributed equally to this work.
Gamete fertility and ovule number variation in selfed reciprocal F1 hybrid triploid plants are heritable and display epigenetic parent-of-origin effects
Article first published online: 31 JAN 2013
© 2013 The Authors. New Phytologist © 2013 New Phytologist Trust
Volume 198, Issue 1, pages 71–81, April 2013
How to Cite
Duszynska, D., McKeown, P. C., Juenger, T. E., Pietraszewska-Bogiel, A., Geelen, D. and Spillane, C. (2013), Gamete fertility and ovule number variation in selfed reciprocal F1 hybrid triploid plants are heritable and display epigenetic parent-of-origin effects. New Phytologist, 198: 71–81. doi: 10.1111/nph.12147
- Issue published online: 25 FEB 2013
- Article first published online: 31 JAN 2013
- Manuscript Accepted: 8 DEC 2012
- Manuscript Received: 14 JUL 2012
- Science Foundation Ireland. Grant Numbers: 02/IN.1/B49, 08/IN.1/B1931
- Irish Department of Agriculture, Fisheries and Food. Grant Number: RSF 07-534
- the Irish Research Council for Science, Engineering and Technology. Grant Number: R 12345
- National University of Ireland Thomas Crawford Hayes Research Fund
- F1 hybrid;
- natural variation;
- parent-of-origin effect;
- Polyploidy and hybridization play major roles in plant evolution and reproduction. To investigate the reproductive effects of polyploidy and hybridization in Arabidopsis thaliana, we analyzed fertility of reciprocal pairs of F1 hybrid triploids, generated by reciprocally crossing 89 diploid accessions to a tetraploid Ler-0 line.
- All F1 hybrid triploid genotypes exhibited dramatically reduced ovule fertility, while variation in ovule number per silique was observed across different F1 triploid genotypes. These two reproductive traits were negatively correlated suggesting a trade-off between increased ovule number and ovule fertility. Furthermore, the ovule fertility of the F1 hybrid triploids displayed both hybrid dysgenesis and hybrid advantage (heterosis) effects.
- Strikingly, both reproductive traits (ovule fertility, ovule number) displayed epigenetic parent-of-origin effects between genetically identical reciprocal F1 hybrid triploid pairs. In some F1 triploid genotypes, the maternal genome excess F1 hybrid triploid was more fertile, whilst for other accessions the paternal genome excess F1 hybrid triploid was more fertile.
- Male gametogenesis was not significantly disrupted in F1 triploids. Fertility variation in the F1 triploid A. thaliana is mainly the result of disrupted ovule development. Overall, we demonstrate that in F1 triploid plants both ovule fertility and ovule number are subject to parent-of-origin effects that are genome dosage-dependent.