Polymorphism for interspecific hybridisation within a population of wild radish (Raphanus raphanistrum) pollinated by oilseed rape (Brassica napus) |
| |
Authors: | G Guéritaine H Darmency |
| |
Institution: | (1) Unité de Malherbologie et Agronomie, Institut National de la Recherche Agronomique, BP 86510, 21065 Dijon, France e-mail: darmency@dijon.inra.fr Tel.:+33-380-69-31-86, Fax:+33-380-69-32-62, FR |
| |
Abstract: | The within-population polymorphism of wild radish (Raphanus raphanistrum) for interspecific hybridisation with two cultivars of oilseed rape (Brassica napus) was investigated by hand crossing experiments and fluorescence microscopy. Wide variability among plants was observed in
the ability of oilseed rape pollen to germinate on the wild radish stigma; the frequency of pistils showing pollen tubes ranged
from 0 to 1, depending on the female plant. The ratio of fertilised ovules to the total number of ovules in ovaries where
pollen tubes arrived ranged from 0.02 to 0.51. Overall, the results provide evidence for the presence of different phenotypes.
In 40% of the plants, pistils had no or very few pollen tubes and few fertilised ovules. In 23%, the foreign pollen tubes
grew through the style towards the ovary, but had low ovule fertilisation efficiency. The remaining 37% showed a large number
of pollen tubes in the style and frequent ovule fertilisation, and two plants showed no difference between foreign and conspecific
pollen. With regard to post-zygotic barriers, pollen germination and ovule fertilisation represent minor barriers to interspecific
hybridisation between oilseed rape and wild radish. It is suggested that the effectiveness of these barriers could be improved
through plant breeding; this could reduce the risk of gene flow from transgenic oilseed rape to populations of wild relatives.
Received: 15 April 2001 / Accepted: 24 May 2001 |
| |
Keywords: | Brassica napus Raphanus raphanistrum Interspecific incompatibility Polymorphism Gene flow |
本文献已被 SpringerLink 等数据库收录! |
|