REDUCTION OF ROOT-LESION NEMATODES (PRATYLENCHUS PENETRANS) IN TUBERS OF POTATO (SOLANUM TUBEROSUM) DURING COLD STORAGE

The effect of storage duration at low temperatures on numbers of the nematode Pratylenchus penetrans harbored within potato tubers of cvs. Superior, Monona, Saginaw, Saginaw Gold, Yukon Gold, and Kennebec were studied from 1992 to 1995. Numbers of P. penetrans in potato tubers held at 1-5?°C for 8 months decreased to nearly zero, regardless of cultivar. The number of nematodes decreased at different rates when stored at 3-5°C than when stored at 1-3°C and decreased most rapidly during the first 2 months of storage at 1-3°C; at 3-5°C storage, it took 4 months for the numbers to decrease substantially. The number of live nematodes in potato tubers after 8 months of storage below 5°C was too low to pose a significant threat at planting to already infested fields, but would still be a source of a new infestation.