Effect of NaCl on Biochemical Changes and Endophytic Fungal Assemblages in the Leaves of a Mangrove, Ceropsis roxiphorguna Arn

One of the universal protective responses of plants to any type of stress is the accumulation of low-molecular organic substances such as amino acids, sugars and proteins. In this study, the effect of salinity on leaf pigments, proteins, free amino acids, proline, polyphenols, sugars and starch content was investigated. Status on endophytic fungal assemblages in the salt treated leaves of a mangrove, C. roxburghiana was studied under hydroponics pot culture. The photosynthetic pigments, sugars and protein concentrations of leaves were reduced by salinity and that the effect was aggravated by the long duration of salinity. Total contents of both chlorophyll and carotenoids decreased significantly by the treatment of NaCl. Total amino acid pool decreased by salinity, but the proline content increased only marginally. In the control, proline level did not change during the entire period of the study. The significant increase of accumulation of proline in leaves is implicated in osmotic adjustment to salinity. The endophytic fungal assemblage was also investigated. Among the 7 species, isolated Phyllosticta sp. was found frequently more when compared to other fungi. The results show that the endophytic fungi like Pestalotiopsis sp. and Phyllosicta sp. can be sustained and regenerated at low salinity condition in halophytes.