Location: Small Grains and Potato Germplasm Research
Project Number: 2050-21000-036-020-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jul 1, 2024
End Date: Sep 15, 2026
Objective:
Research objectives include collecting tuber greening, total glycoalkloids, sugars, cold tolerance, and cold sweetening resistance on a biparental segregating mapping population grown under field conditions with standard agronomic practices applied for potato. Further, the parents and a grandparent of the population will undergo whole genome sequencing using long read technologies (third generation sequencing) in order to improve their current genome assemblies. The overarching objective is to identify genetic signals for these complex traits important to the potato industry and ultimately develop molecular markers for key traits for rapid selection in a laboratory setting.
Approach:
The A201085 population consisting of almost 270 individuals will be grown out in the field in Aberdeen, ID and tubers will be evaluated for tuber greening. Greening will be measured by placing tubers in a chamber and exposing them to constant light for five days. After illumination, greening will be measured using an assay to quantify total chlorophyll content of freeze-dried tubers that were exposed to light. Chlorophyll content measurements will allow for the subjectivity of visually measuring greening intensity by the human eye to be removed and further help to differentiate smaller differences in tuber greening among the clones. The top most resistant and susceptible tubers will be placed under lights for a long period of time (~20 days) to evaluate how long the resistant tubers resist greening. This population will also be used to measure total glycoalkaloids (on light exposed tubers and tubers kept in the dark) and subsequently analyzed to evaluate if there is a strong correlation between greening and glycoalkaloid production. Further, sugars, cold tolerance, cold sweetening resistance and other morphological traits of interest segregating in the population will also be evaluated. Phenotypic data will be collected and combined with genotyping data and analyzed for genetic signals associated with resistance to greening along with the other traits collected in this work. Potato genetic linkage maps for this population have already been constructed by MAPpoly, which is an R-package, focusing on the creation of linkage maps for polyploids. QTL analyses will be employed using QTLpoly utilizing the phenotypic and genotypic data collected on individuals from the A201085 population. Plants for genome sequencing will be grown in pots in the greenhouse and tissue will be harvested, flash frozen, and sent to a service provider for sequencing services (3rd generation sequencing). The sequence data in this project generated will help improve the current genome assemblies.
