Evaluating Regeneration Capability of Selected Diploid Potato Germplasm to Accelerate Diploid Breeding

THILANI JAYAKODY; SATYA SWATHI NADAKUDUTI; MASSA GABRIELA ALEJANDRA; DAVID DOUCHES

Congreso; Potato Association of America Meeting; 2019

Advancementsin breeding of cultivated tetraploid potato (Solanum tuberosum L.2n=4x=48) have been limited by the retention of a heterozygous, polyploidgenome through centuries of asexual reproduction. To address these limitations,breeding efforts have been geared toward a diploid inbred line system. Thereduction in genetic complexity of diploids more readily permits the use ofgenome editing tools such as CRISPR/Cas9. The current impediment to the use ofgenetic engineering in diploids is that most of the germplasm available eitherhas poor tuber quality, self-incompatibility or low regeneration efficiency. This study tested the regeneration efficiency ofnine diploid lines from the MSU diploid recurrent selection and backcrossprograms selected based on their self-compatibility and improved tuber traits. Additionally,US-W4, from Wisconsin, and 1S1, from Virginia Tech., were also included in thestudy. The regeneration efficiency of these eleven lines ranged from 0-80%. Thebest five tissue culture regenerant lines were selected for further greenhousetesting. Identification of diploid germplasm with traits including good tuberquality, self-compatibility and regeneration/genetic transformation capability providesdiploid material to perform genetic studies and genome editing and furtheraccelerate the potato diploid breeding efforts.