Modern potato varieties are tetraploid, with four copies of each chromosome (compared to diploids, which have 2 copies of each chromosome). Tetraploids tend to have a higher yield than diploids due to posessing larger cells. However, genetic improvement through breeding at the tetraploid level in potato is inefficient. More genetic gain could be made by breeding at the diploid level, to accumulate useful traits, followed by transferring these accumulated traits back to the tetraploid level by crossing the diploid breeding clones with tetraploids. This novel process is called Fixation_Restitution Breeding, and DIFFUGAT is developing the tools (breeding germplasm and genomic resources) to enable it.
In order to rapidly accumulate and fix desirable characteristics in diploid potato, it is necessary to be able to self pollinate (or inbreed) them. However, diploid potato has a genetic system that prevents this. Overcoming this system of "self-incompatibility" (SI) is the first of two major requirements of Fixation-Restitution Breeding. To date, the major result of the project is the identification of a "self-compatibility" (SC) gene, widespread in potato, that enables the SI system in potato to be overcome, allowing diploid potatoes to be self pollinated. Genetic markers have been developed for the SC gene, enabling breeders to use a process called marker assisted selection to propagate the gene in diploid breeding material.
*At the time of the proposal. Please consider this data as an accurate estimate; it may vary during the project’s lifespan.
Total costs include in kind contribution by grant holders and can therefore be higher than the total requested funding.