Name
Diploid breeding for red potatoes
Date & Time
Tuesday, July 19, 2022, 8:45 AM
Maria CARAZA-HARTER
Description

Developing new potato varieties is currently challenging due to the tetraploid nature of the crop: having four sets of chromosomes makes it difficult to maintain favorable allele combinations and eliminate deleterious alleles from the gene pool. Recent efforts towards creating a new paradigm for potato breeding involve converting potato into a diploid, inbred-hybrid crop. To generate uniform predictable hybrid offspring, the first step is to develop inbred parent lines. This is nearly impossible in autotetraploids but achievable in diploids. Our breeding program started the diploid breeding of red potatoes by selecting five elite red tetraploids clones (4x) and crossing them with the haploid inducer IVP101. Diploidy (2x) was confirmed for 199 dihaploid progeny by guard cell chloroplast counts and SNP array genotyping. The dihaploids were pollinated by self-compatible clones from our round white diploid breeding program, and 19 F1 populations were selected based on the yield of true potato seed (TPS) and maternal tuber type. A total of 561 F1 diploid seedlings were grown and self-pollinated in the greenhouse, from which 25% were self-fertile. F2 populations were selected based on TPS and tuber yield in the F1 generation. F2 populations will be evaluated in the Summer of 2022 based on similar criteria, as well as percent homozygosity. Our goal is to identify superior F3 individuals with over 50% homozygosity to begin the next breeding cycle.

Session Type
Oral
Parent Session
7/19 - Concurrent Sessions D