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    CSU Potato Program Website!
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    • San Luis Valley Research Center: 719-754-3594
    • Potato Certification Service: 719-754-3496

Current Post Harvest Test Results

Current Post Harvest Test Results Home

Current Post Harvest Test Results

Certification of seed lots is completed at the Post Harvest Test (PHT) plots. At harvest, growers sample every seed lot that passes summer inspection and PCS plants those samples in a warm location. Oahu, Hawaii is being used as our PHT plot location. Samples are planted in early December. Plants are inspected in early to mid-January. These inspection results estimate virus spread that happens late in the summer growing season, after summer inspections but before vine killing. The results are used to determine seed sales eligibility of lots already in storage, and recertification eligibility of seed lots for the following growing season.
Based on new regulations in the Colorado Seed Act, only seed potatoes with a total mosaic level of less than 5.0% can be planted in Colorado. Below there are two different PHT lists: the 1st list contains certified seed that can be planted back in Colorado, the 2nd list contains seed that is certified and can be sold out of state.

2016 Post Harvest Test Results (Seed Available for Replant in Colorado)
2016 Post Harvest Test Results (Seed Available for Out of State Sales)