The objective of this work was to evaluate the effect of eucalyptus biochar on the transpiration rate of upland
rice 'BRSMG Curinga' as an alternative means to decrease the effect of water stress on plant growth and development.
Two‐pot experiments were carried out using a completely randomized block design, in a split-plot arrangement, with
six replicates. Main plots were water stress (WS) and no‐water stress (NWS), and the subplots were biochar doses at 0,
6, 12 and 24% in growing medium (sand). Total transpirable soil water (TTSW), the p factor – defined as the average
fraction of TTSW which can be depleted from the root zone before water stress limits growth –, and the normalized
transpiration rate (NTR) were determined. Biochar addition increased TTSW and the p factor, and reduced NTR.
Consequently, biochar addition was able to change the moisture threshold (p factor) of the growing medium, up to 12%
maximum concentration, delaying the point where transpiration declines and affects yield.