Means of model parameters calibrated on four environments.

About 11 degree days (°Cd) is equivalent to 1 day. SE = Standard error of the mean; * = significant P<0.05; ** = significant P<0.01; *** = significant P<0.001; F0: initial fraction of light interception; R0: rate of relative increase of light interception in °C−1d−1; d: twice the duration from t0.5 to the end of the light interception in °Cd; t0.5: time when the fraction of light intercepted is reduced to 50% of its maximum value attained at MCC (t0.5); TIO: tuber initiation onset in °Cd; and (TM): tuber growth cessation or maturation in °Cd.