Physical and chemical mutagenesis as tools for genetic improvement in potato
Date & Time
Monday, July 18, 2022, 3:15 PM
Oluwafemi Omilani

New Plant-Breeding Techniques (NBTs) such as genetic engineering and gene editing provide a suite of resources for plant breeders to efficiently improve desired qualities in crops of interest. However, their adoption is limited by attendant issues including ethical concerns, government regulations, and huge approval costs. Genetic variation remains a seminal tool in the breeders arsenal for both conventional and NBT approaches. Mutation breeding offers advantages over NBTs, including direct release of mutants as new varieties. Physical and chemical treatment of plant materials are two primary methods used to introduce mutations in plants. In this study we employed gamma radiation and ethyl methane sulfonate (EMS) as mutagens to induce genetic variation in three potato clones: Umatilla Russet, Castle Russet and AO02183-2. One-week old internodal cuttings were exposed to seven radiation doses (5, 10, 20, 30, 40, 50 and 60 grays) for gamma radiation, while for EMS, the internodal cuttings were treated with twelve different doses (0.25%, 0.50%, 0.75% and 1% at 30 minutes, 1 hour and 2 hours). The putative mutants which survived after exposure to the mutagenic agents are being screened for Fusarium dry rot, total glycoalkaloids and pectin methylesterase activity. The preliminary results show that while all three clones generated putative mutants, the LD50 varied for the three clones using both mutagenic agents. The putative mutants were SNP genotyped to investigate the level of induced mutations for each treatment. A total of 317 gamma radiation and 523 EMS putative mutants were induced. The mutants can serve as valuable genetic stock and also have the potential to be released directly as a new variety. Further investigations could also provide information on the association between the putative mutant loci and mutant phenotypes.

Session Type
Parent Session
7/18 - Concurrent Sessions A