Figure 3.

Polynomial temperature profiles (grey line) in cold-treated (left) and warm-treated (right) plant cylinders calculated during measurements of RERs. Data of the three cold water baths were averaged. Boxplots display the hourly temperature readings for each sensor depth. Boxes comprise the 25–75 % quantiles with the median as vertical line, dots indicate outliers. The deepest temperature sensor was located at −140 mm depth. Similar polynomial regressions were made for each RER 12 h⁻¹ to estimate root tip temperatures.