Generating self-incompatible hybrid potatoes through haploid breeding

Heterosis arising from hybrid breeding has been instrumental in the improvement of crop yield and quality^1,2. In self-pollinating crops, the use of male-sterile lines facilitates the production of hybrid seeds³. However, hybrid breeding in asexually propagated crops such as potato (Solanum tuberosum L.) presents challenges not only in hybrid seed production but also due to competition between above-ground (fruit) and below-ground (tuber) sinks. Here we developed self-incompatible homozygous diploid potatoes and hybrids through haploid breeding. This approach enables large-scale, low-cost hybrid seed production and eliminates aerial fruit formation, thereby avoiding sink competition between fruits and tubers and achieving a streamlined breeding design. Our strategy elevates the harvest index of hybrid potatoes, offering a paradigm for using heterosis and maximizing yield potential in asexually propagated crops.