Adaptive mechanism in Quercus brantii Lindl. leaves under climatic differentiation: morphological and anatomical traits

Leaf traits, which vary across different climatic conditions, can reveal evolutionary changes within a species made to adapt to the environment. Leaf traits play major roles in a plant functions under varying climatic conditions. To examine adaptive modes and mechanisms applied by plants in different climates, we analyzed leaf morphology and anatomical structures in Quercus brantii in the Zagros forests, Western Iran. The plants adapted to the environmental differences with increased dry matter content in a Mediterranean climate, and increasing leaf length, specific leaf area, stomata length (SL), stomata width, stomatal density (SD), stomatal pore index (SPI), trichome length, and width in a sub-humid climate; trichome density was increased in a semi-arid climate. There were strong, positive correlations between SPI with SL and SD. Correlations for other leaf traits were weakly significant. Such morphological and anatomical plasticity probably leads to lower transpiration rates, control of internal temperature and water status, and improved photosynthetic capability under stressing conditions. These findings provide new insights into the adaptive strategies of plants to environmental changes at the morphological and anatomical levels.

Automated summary

Leaf traits vary across different climatic conditions and can reveal evolutionary changes within a species made to adapt to the environment. In this study, leaf morphology and anatomical structures were analyzed in Quercus brantii in Western Iran to examine the adaptive strategies of plants in different climates. The plants showed increased dry matter content in a Mediterranean climate and increased leaf length, specific leaf area, stomata dimensions, trichome dimensions, and trichome density in different climatic conditions. Strong correlations were found between stomatal pore index and stomata dimensions. These findings provide insights into the adaptive strategies of plants to environmental changes at the morphological and anatomical levels.