section_path: Breeding
section_name: Breeding
paragraph_text: Breeding
  
  Potatoes, both S. tuberosum and most of its wild relatives, are self-incompatible: they bear no useful fruit when self-pollinated. This trait is problematic for crop breeding, as all sexually-produced plants must be hybrids. The gene responsible for self-incompatibility, as well as mutations to disable it, are now known. Self-compatibility has successfully been introduced both to diploid potatoes (including a special line of S. tuberosum) by CRISPR-Cas9. Plants having a 'Sli' gene produce pollen which is compatible to its own parent and plants with similar S genes. This gene was cloned by Wageningen University and Solynta in 2021, which would allow for faster and more focused breeding.
  
  Diploid hybrid potato breeding is a recent area of potato genetics supported by the finding that simultaneous homozygosity and fixation of donor alleles is possible. Wild potato species useful for breeding blight resistance include Solanum desmissum and S. stoloniferum, among others.