Low-temperature stress induces transient oscillations in sucrose metabolism in Solanum tuberosum.

Exposure to low but nonfreezing temperatures induces the net breakdown of starch and the accumulation of sucrose, glucose and fructose in potato tuber tissue, a complex phenomenon known as low-temperature sweetening (LTS). When transferred to 4 degrees C storage, tissue sucrose levels in LTS-sensitive potato tubers (Solanum tuberosum cv. Norchip) did not change monotonically to a new steady state, but rather transiently oscillated about the trajectory to the new steady state. The dynamic patterns observed in sensitive tubers grown in 1993 and 1994 were qualitatively similar. Quantitatively, however, the transient oscillation had a period of 11.5 days in 1993, whereas a period of 80 days was observed in 1994. In contrast, the sucrose levels of the LTS-tolerant potato tubers (Solanum tuberosum seedling ND860-2) increased monotonically to a higher level upon exposure to low temperatures.