RESELECTION HELPS GROWERS GET BEST SEED
ST. ANTHONY, Idaho—Dirk Parkinson adds an extra step to producing seed potatoes, believing it improves yields, tuber size and uniformity and may even hold the potential to limit the spread of diseases.
After row closure in his first-generation fields, the St. Anthony grower flags the 500 hills that look healthiest and best fit his criteria. From that pool, Parkinson singles out an ideal individual tuber to parent a new line of the same variety.
Re-selecting is intended to maintain performance while minimizing gradual drift away from a variety's desirable attributes. Parkinson also uses reselection to whittle out genetic problems that tend to surface in specific varieties.
University of Idaho heats the chosen seed to kill diseases, and it's screened for pathogens by Idaho Crop Improvement Association. UI then produces plant tissue cultures from the tuber—exact clones of the parent increased exponentially through stem cuttings.
Parkinson re-selects annually for Russet Burbank, Ranger Russet and Alturas, raising the university-supplied plantlets in an isolated greenhouse near Challis to produce his own pre-nuclear mini-tubers, which are planted again as nuclear seed. The following three seasons of re-plantings are considered generations 1, 2 and 3.
Parkinson estimates 2–3 percent of seed growers use re-selection programs, and much of the seed material on the market hasn't been re-selected in decades.