Location: Genetic Improvement for Fruits & Vegetables Laboratory
Project Number: 8042-21000-305-028-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2025
End Date: Aug 31, 2026
Objective:
Identify diploid potato breeding clones that have resistance to common scab (Streptomyces sp.) and/or tolerance to heat stress. Calculate breeding values and conduct a genome-wide association study to determine regions of the diploid potato genome associated with common scab and heat resistance.
Approach:
At USDA-ARS and the University of Florida, diploid potato breeding is a focus of ongoing research efforts. This is part of a national effort to develop uniform true potato seed, which can replace seed tubers at the early stages of commercial seed tuber production. To determine the response to heat stress, seed tubers from the selected diploids will be planted at the Hastings Agricultural Extension Center in Hastings, Florida. The trial will include planting during the typical planting season in January, and a late planting in February. The late planting will likely experience higher heat stress during the later growing season. The typical and late planted plots will be harvested and traits such as yield, specific gravity, and the frequency of internal defects will be collected to compare performance in normal and heat stress conditions. ARS diploid potato breeding clones that were assessed for heat tolerance will be genotyped on the Illumina SNP array V4. The scab resistance data will be analyzed together with the genotype data to calculate genomic prediction models and breeding values for heat tolerance.