Modelling Leaf Temperatures during Parabolic Flights*

A code was generated in MATLAB to model the temperature of plant (Arabidopsis) leaves (T) during 25 s periods of hypo- (μg) and hyper- (2g) gravity (g) produced by parabolic flights. Temporal data T(t) vary inversely with g(t) and are reproduced by a model that accounts for heat transfer across the boundary layer (BL) between the leaf and air [1,2], conduction through the stem into the growth media, and heat from the plant metabolism. While the BL and stem conduction terms are analytically known, the metabolic power is approximated as a function of T to simulate the T(t) data. Extending the metabolic power term to include time dependent dose-response mechanisms requires comparison of model predictions to T(t) data from longer periods of low-g. Thus, analysis of T(t) data from parabolic flights simulating lunar gravity over longer times will check the fully adaptive T(t) at low-g. Sub-orbital flights with 5 min periods of μg will test further extensions of the model.
[1] Y. Kitaya et al., Plant, Cell & Environment 26 (2003) 497.
[2] M. Sandreau et al., FSPM-2013 Proceedings (2013), https://ojs.silvafennica.fi/index.php/fspm2013/article/view/724.