Bulbophyllum weddellii (Orchidaceae) demonstrates foliar water uptake plasticity along Brazilian campos rupestres

Phenotypic plasticity can facilitate species survival in a variety of conditions that are not possible with a fixed phenotype. Foliar water uptake (FWU), defined as the absorption of water through leaf surfaces, is an important mechanism contributing to plant water balance and drought tolerance in many species. It is known that FWU varies within species at the landscape scale, showing phenotypic variability. Here, we investigated the plasticity of FWU capacity across Bulbophyllum weddellii populations and its potential adaptive value using a common garden experiment. FWU was higher in plant populations from more humid environments, but leaves from the same plants grown in a greenhouse show no difference regarding FWU. Thus, this study confirmed that B. weddellii leaves have physiological plasticity in relation to FWU. This plasticity may enable establishment in distinct environments and explain the wide distribution of this species. More broadly, our findings suggest that FWU plasticity can contribute to plant persistence in seasonally and climatically variable ecosystems, with important implications for species responses to ongoing climate change.