Mapping resistance to the Potato Cyst Nematode, Globodera pallida, in a tetraploid, russet-skinned potato population
Date & Time
Monday, July 18, 2022, 2:30 PM

Globodera pallida is a quarantined pest of potato in the United States and has had a significant economic impact on the Idaho potato industry. In the western United States, the predominant market class is for processing and is represented by long tuber shape and russet skin, which have historically lacked breeding for potato cyst nematode (PCN) resistance. European G. pallida is classified into three pathotypes (Pa1-Pa3) based in their virulence reactions on different potato genotypes. Previous studies have identified in the Scottish cultivar Eden resistance locus GpaIVsadg which confers resistance to Pa2 and Pa3. In this study, QTL analysis was conducted on a tetraploid population derived from PCN resistant Eden and susceptible Western Russet. A total of 245 offspring, four cultivar controls and four PCN differential clones were evaluated. Phenotypic evaluation involved transfer of tissue culture plantlets to pots and inoculated with 5 eggs per gram of soil with an average of 10 replicates per genotype. The phenotypic data for PCN resistance response was converted to best linear unbiased prediction (BLUP). The SolCap 21,027 SNP chip was used for genotyping the entire population. Quantitative trait linkage (QTL) mapping was performed for five traits, including cyst and egg-related phenotypes. The linkage map and BLUP data were imported into R-package QTLpoly. Preliminary results indicate that nine lines were classified as resistant to G. pallida, 130 lines were classified as partially resistance and 106 lines were susceptible when were compared with Russet Burbank. Moreover, primary QTL associated with PCN resistance were detected on chromosomes 4 and 6 with heritability estimates ranging from 0.10 to 0.20. This study will help to further characterize PCN resistance from Eden and identify genetic regions valuable for PCN resistance in oblong, russet-skinned processing potatoes.

Session Type
Parent Session
7/18 - Concurrent Sessions A