Kompetitive Allele Specific PCR (KASP) Markers for Potato: An Effective Tool for Increased Genetic Gains

Potato virus Y (PVY) and Phytophthora infestans (Mont.) de Bary that causes potato late
blight (LB), pose serious constraints to cultivated potatoes due to significant yield reduction, and
phenotyping for resistance remains challenging. Breeding operations for vegetatively propagated
crops can lead to genotype mislabeling that, in turn, reduces genetic gains. Low-density and low-cost
molecular marker assessment for phenotype prediction and quality control is a viable option for
breeding programs. Here, we report on the development of kompetitive allele specific PCR (KASP)
markers for LB and PVY resistance, and for routine quality control assessment of different breeding
populations. Two KASP markers for LB resistance and two for PVY Ryadg were validated with
an estimated assay power that ranged between 0.65 and 0.88. The developed QC KASP markers
demonstrated the capability of discriminating tetraploid calls in breeding materials, including fullsibs and half-sibs. Routine implementation of the developed markers in a breeding program would
assist with better allocation of resources and enable precise characterization of breeding material,
thereby leading to increased genetic gains.