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Studies that simulate recurrent drought events with subsequent episodes of rehydration better reflect natural conditions and allow visualization of differential acclimatization responses resulting from memory and tolerance mechanisms. Piper aduncum and Piper tuberculatum were grown in a greenhouse and were subjected to three successive cycles of drought and subsequent rehydration. After suspending irrigation, gas exchanges were measured daily with IRGA. When stomatal conductances close to zero were obtained, the plants were rehydrated and kept irrigated. In P. tuberculatum, stomatal conductance was always higher after periods of rehydration compared to the period before the drought, while the transpiration rate was lower only during the drought. The damage to the photosynthetic apparatus was caused by the influence of the interception of the flow of electrons in the transport chain. We came to the conclusion that the dehydrated plants showed an alert signal, which triggered response mechanisms to prevent or deal with the water stress situation.

This study investigates how cocoa rootstocks respond to flooding and post-flooding conditions, offering insights for cocoa plantation sustainability in flood-prone areas due to climate change. We studied Theobroma cacao L. rootstocks for 60 d of flooding and 30 d post-flooding, grafting PS-1319 scions onto five rootstocks (TSH-1188, Cepec-2002, Pará, Esfip-02, SJ-02). Photochemical performance remained stable across rootstocks, while flooding progressively reduced electron transport efficiency. Photochemical damage emerged after 7 d, worsening occurred at 19 d. Although post-flooding efficiency improved, recovery time was insufficient for full restoration. Stem diameter increased less in Esfip-02. TSH-1188 had the highest stem dry mass during flooding and the most root and total dry mass during post-flooding. SJ-02 had the lowest stem dry mass and post-flooding total dry mass. Principal component analysis revealed stem and root development as a key for recovery. SJ-02 and Esfip-02 showed lower flooding tolerance and recovery, while TSH-1188 and Pará exhibited higher resilience.