Poster: Emerging technologies

Abs # 907: Reverse breeding: a novel plant breeding concept

Presenter:	Lelivelt, Cilia CLC, c.lelivelt@rijkzwaan.nl
Authors	Lelivelt, Cilia CLC (A)   van Dun, Kees CMP (A)   Touraev, Alisher A (B)   Dirks, Rob RHG (A)
Affiliations:	(A): Rijk Zwaan Breeding BV (B): University of Vienna
Web Site:	http://www.rijkzwaan.nl

Plant breeding operates through iterative cycles of recombination and selection in order to produce elite varieties optimally adapted to local growing conditions. Varieties of many crops are produced as F1 hybrids which are developed by an initial phase of line selection followed by a phase in which experimental hybrids, resulting from different combinations of lines, are tested for their agricultural or horticultural value. Technologies which enable a more efficient operation of the plant breeding cycle are of considerable interest for the commercial plant breeder. As the understanding of meiotic recombination at the molecular level is rapidly increasing, breeding tools will be developed which ultimately allow to control this process. We are exploring downregulation of meiotic recombination to develop a concept which has been termed reverse breeding. Reverse breeding is a process in which the order of events leading to the production of a hybrid plant variety is essentially reversed. Initially, individual heterozygous plants are selected for their qualities and, subsequently, lines are derived from these plants which upon hybridisation reconstitute the original genetic composition of the selected plant from which the lines are derived. This process is pursued through downregulation of genes like DMC1 and SPO11 through RNAi, combined with doubled haploid technology. RNAi constructs are currently transformed to both model as well as crop species to determine their efficacy in suppressing meiotic recombination.This novel plant breeding approach offers clear advantages over existing methods due to the fact that in principle any heterozygous plant can now be commercially exploited through re-synthesis of its genetic constitution by the formation of an F1 hybrid.