Scalon, Silvana de Paula Quintão creator Kodama, Flávia Mitsuko creator Dresch, Daiane Mugnol creator Pereira, Zefa Valdivina creator Mussury, Rosilda Mara creator Scalon, Lourenço Quintão creator text periodical abstract or summary bl. continuing eng Abstract In this study, we assessed the gas exchange in Caryocar brasiliense seedlings in water deficit conditions and their capacity to recover after rehydration. We assessed plant photosynthetic rates, internal carbon concentrations, stomatal conductance, transpiration rates, water-use efficiency, instantaneous carboxylation efficiency, chlorophyll index, and photosystem II quantum efficiency. All gas exchange parameters were reduced after the suspension of irrigation. Seedling photosynthetic rates approached zero after 12 days. The equilibrium was reestablished in all variables 11 days after re-initiating irrigation, with the exception of internal CO2 concentration and stomatal conductance. Exposure of seedlings to water stress resulted in drastically reduced photosynthetic processes. This reduction occurred due to the limitation of stomatal conductance and low rubisco carboxylation efficiency but not to irreversible damage photosystem II. All of these parameters demonstrated recuperation with rehydration, but only the photosynthetic rates reached initial control values. Keywords: hydric stress, native fruit, Pequi, Caryocaceae Publicação on-line; 27 ref.; 3 illus.; Summary (En) CARYOCAR BRASILIENSE PEQUI DEFICIÊNCIA HÍDRICA Rio de Janeiro-RJ Instituto de Florestas - UFRRJ 1994 2025-0456 1415-0980 / ISSN 2179-8087 0nline BR2026001261 v. 27(2) p. 1-8; (2020) https://www.scielo.br/j/floram/a/zTZ9R5cgfGLDk9QKrjYTSHw/?format=pdf&lang=en https://www.scielo.br/j/floram/a/zTZ9R5cgfGLDk9QKrjYTSHw/?format=pdf&lang=en BR-BrBNA 260520 20260520193154.0 eng