Performance and Market Potential of EMS-Induced Mutagenic Diploid Potato Germplasm in Multi-Year Field Trials

Commercial potato (Solanum tuberosum L.) production has traditionally relied on tetraploid potato cultivars, as tetraploidy was long considered essential for high yield. This assumption is now being challenged, renewing interest in diploid breeding. In this study, an ethyl methane sulfonate (EMS)-mutagenized diploid potato germplasm collection consisting of 721 clones was assessed for tuber quality appearance and dormancy, and a subset of 54 clones was evaluated for marketable yield across multi-year field trials in comparison with 6 tetraploid checks. The collection exhibited broad phenotypic diversity: 86% produced acceptable to excellent tubers, and 80% showed good to high dormancy. Market class distribution included 55% creamer (small tubers), 41% table/chip (round, moderately large), and 4% frying types. Among the 54 clones tested for yield, 74% of creamer types matched tetraploid checks, and 17% outperformed them; 70% of table/chip clones yielded comparably to tetraploid checks. For Canada N°1 marketable yield, 20% of creamer and 29% of table/chip clones equaled or exceeded checks. Frying class clones underperformed, yielding 56% less than checks. All evaluated clones had specific gravity similar to checks, indicating comparable dry matter content for processing. These findings demonstrate that diploid potatoes can rival tetraploids in tuber quality, yield for creamer and table/chip classes, processing suitability, and storability. This work provides a foundation for disseminating high-yield diploid germplasm and advancing diploid breeding strategies, with significant implications for cultivar development and genetic resource utilization in the potato industry.