Reciprocal hybridization at different times between Senecio flavus and Senecio glaucus gave rise to two polyploid species in north Africa and south-west Asia
Article first published online: 25 NOV 2005
Volume 169, Issue 2, pages 431–441, February 2006
How to Cite
Kadereit, J. W., Uribe-Convers, S., Westberg, E. and Comes, H. P. (2006), Reciprocal hybridization at different times between Senecio flavus and Senecio glaucus gave rise to two polyploid species in north Africa and south-west Asia. New Phytologist, 169: 431–441. doi: 10.1111/j.1469-8137.2005.01604.x
- Issue published online: 25 NOV 2005
- Article first published online: 25 NOV 2005
- Received: 28 July 2005 Accepted: 27 September 2005
- amplified fragment length polymorphism (AFLP);
- intergenomic recombination;
- • The analysis of hybrid plant taxa using molecular methods has considerably extended understanding of possible pathways of hybrid evolution.
- • Here, we investigated the origin of the tetraploid Senecio mohavensis ssp. breviflorus and the hexaploid Senecio hoggariensis by sequencing of nuclear and chloroplast DNA, and by analysis of the distribution of taxon-specific amplified fragment length polymorphism (AFLP) fragments.
- • Both taxa originated from hybridization between the diploid Senecio flavus and Senecio glaucus. Whereas S. glaucus was the female parent in the origin of S. mohavensis ssp. breviflorus, S. flavus was the female parent in the origin of S. hoggariensis.
- • The distribution of AFLP fragments suggests that S. hoggariensis is an allohexaploid species with two diploid genomes of S. glaucus and one diploid genome of S. flavus. The high frequency of S. flavus-specific fragments in S. mohavensis ssp. breviflorus is explained either as the result of introgression between a primary hybrid and S. flavus or as the result of intergenomic recombination in a primary hybrid. These two alternative processes cannot easily be distinguished.