If transgenic sunflowers are ever grown in Europe, methods for preventing unwanted out-crossing could facilitate co-existence on the farm. This project aims to evaluate the reliability of cytoplasmic male sterility (CMS) in sunflowers to prevent the flow of transgenic pollen.
In two districts in Bulgaria with correspondingly different climatic conditions, two identical field trials were performed. Seventeen sunflower CMS lines, differing in respect to the origin of cytoplasm and to putative CMS stability, were characterised in respect to genetic authenticity, homogeneity, type of cytoplasm, formation, release and viability of pollen, formation of seeds, and the parentage of seeds.
When the extent of pollen flow is better understood, researchers will suggest practices for using CMS to prevent the spread of transgenes from sunflowers.
The results obtained during the first year of research showed 75 percent decrease of the rate of pollination at a distance of 1 kilometre, and 30 percent decrease at a distance of 1.5 kilometres from the male fertile line. This discrepancy may be explained by the instability of sterility which was observed in the four CMS lines investigated. A microsatellite parentage analysis proved that the male fertile line contributed to the formation of most of the hybrid seeds at distances of 10 metres, 1.0 kilometre and 1.5 kilometres. However, individual seeds were also detected as the result of self-pollination of maternal CMS lines, as well as of cross-pollination between them.
Further experiments were conducted in the second year of research, aimed at investigating the degree of instability of CMS, and at identifying factors affecting the CMS trait in sunflowers. In order to select stable CMS lines for further investigation, research was directed at determining the genetic authenticity and homogeneity of 17 CMS lines and at specifying the identity of plants which release pollen and form seeds.
The research team soon will be releasing a report on the findings from the first growing season.
Public Deliverables of the Co-Extra project
|NAME / ORGANISATION||CONTACT INFORMATION|
|Atanas Atanassov / Tzvetanka Hvarleva|
AgroBioInstitute (ABI), Bulgaria