Leaf plasticity across wet and dry seasons in Croton blanchetianus (Euphorbiaceae) at a tropical dry forest

Plant species of the Brazilian Caatinga experience seasonal wet and dry extremes, requiring seasonally different leaf characteristics for optimizing water availability. We investigated if Croton blanchetianus Baill exhibits leaf morphoanatomical traits across seasons and positioning in sunlight/natural shade. Leaves of ten 1-3 m tall plants in full sunlight and ten in natural shade were assessed in May, July (wet season), October and December (dry season) 2015 for gas exchange, leaf size, lamina and midrib cross sections (14 parameters), and chloroplast structure (5 parameters). Net photosynthesis was greater during the wet season (21.6 µm −2 s −1 ) compared to the dry season (5.8 µm −2 s −1 ) and was strongly correlated with almost all measured parameters ( p