Dataset Information

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

ABSTRACT: 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 < 0.01). Shaded leaves in the wet season had higher specific leaf area (19.9 m² kg^-1 in full-sun and 23.1 m² kg^-1 in shade), but in the dry season they did not differ from those in full sun (7.5 m² kg^-1 and 7.2 m² kg^-1). In the wet season, the expansion of the adaxial epidermis and mesophyll lead to larger and thicker photosynthetic area of leaves. Furthermore, chloroplast thickness, length and area were also significantly larger in full sunlight (2.1 μm, 5.1 μm, 15.2 μm²; respectively) and shaded plants (2.0 μm, 5.2 μm, 14.8 μm²; respectively) during wetter months. Croton blanchetianus exhibits seasonal plasticity in leaf structure, presumably to optimize water use efficiency during seasons of water abundance and deficit. These results suggest that the species is adaptable to the increased drought stress projected by climate change scenarios.

SUBMITTER: Mendes KR

PROVIDER: S-EPMC8770520 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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

Mendes Keila Rêgo KR Batista-Silva Willian W Dias-Pereira Jaqueline J Pereira Marcos P S MPS Souza Eliane V EV Serrão José E JE Granja João A A JAA Pereira Eugênia C EC Gallacher David J DJ Mutti Pedro R PR da Silva Duany T C DTC de Souza Júnior Rogério S RS Costa Gabriel B GB Bezerra Bergson G BG Silva Cláudio M Santos E CMSE Pompelli Marcelo F MF

Scientific reports 20220119 1

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 ...[more]

PMID: 35046463

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Dataset Information

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

Publications

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

Similar Datasets

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