Tropical Plant Research

Farzana Akter Jake, Md. Habibur Rahman, Md. Abul Kashem and Mohammad Zabed Hossain*

*Department of Botany, University of Dhaka, Dhaka 1000, Bangladesh

DOI: https://doi.org/10.22271/tpr.2020.v7.i2.053

Abstract:
Plant traits are often studied to understand the mechanisms of adaptation to their environment. The present study examined whether leaf traits (e.g. specific leaf area, leaf size, leaf breadth, leaf length, chlorophyll content, water content, relative water content, dry matter content and stomatal size, density, open-close behavior and pore index) of Sal (Shorea robusta) differed between Singra and Madhupur Sal forests those were situated in two different geographical locations in Bangladesh. Fully expanded leaves were collected from five different locations within each forest type during May and December. Soil samples were collected at 0–10 cm depth and analyzed for moisture, pH, conductivity, organic carbon, nitrogen, phosphorus, sodium and potassium. Two-way ANOVA showed that forest type had significant effects on leaf breadth, leaf area, specific leaf area, relative water content and dry matter content where all these parameters showed higher values in Madhupur Sal forest excepting dry matter content which was higher in Singra forest. Season also showed significant effects on open-close behavior of stomata with the highest mean value of open stomata in December in both forests. Principal Component Analysis (PCA) done by using the correlations among the leaf traits showed that both Madhupur and Singra forests were separated from each other during may due to leaf morphological variation and both Madhupur and Singra forests showed a similar trend of seasonal variation due to stomatal behavior. Results obtained in the present study suggested that geographical and seasonal variation of leaf traits of S. robusta might be related to the climatic factors as well as phenological events and such morpho-anatomical variation in leaf traits could be related to their adaptation.