Adaptability of Typha domingensis to environments with high pH and salinity.

MUFARREGE, M. M.; DI LUCA, G. A.; HADAD H. R.; MAINE, M. A.

Miramar

Congreso; 11th International Conference on Salt Lake Research.; 2011

International Society for Salt Lake Research (ISSLR), PROMAR-Ctro. de Zoología Aplicada (UNC), Fundación Mar

To succesfully grow in a saline environment, hallophyte plants must be able to acquire water and avoid accumulating excess salt. Althoug Typha domingensis is a glycophyte species, we observed a healthy state in plants growing under high salinity and pH conditions in a constructed wetland (CW). The aim of this work was to compare the adaptability of two different populations of T. domingensis exposed to high pH and salinity. The plants were sampled from an uncontaminated natural wetland (NW) and a constructed wetland (CW) for the treatment of an industrial effluent with high pH and salinity. The plants from each population were exposed to the following combined treatments of salinity (mg L-1) and pH: 8,000/10 (values found in the CW); 8,000/7; 200/10 and 200/7 (typical values found in the NW). Relative growth rates (RGR) and chlorophyll concentration were measured. Images of roots and leaves by scanning electronic microscopy (SEM) were obtained. In all treatments, the RGR and chlorophyll increase were significantly lower in the plants from the NW than in the plants from the CW. Evident damage in roots and leaves tissues were observed when the plants from the CW were exposed to treatment 200/7. In treatment 8,000/10 the tissues of the plants from the NW showed severe damages. The CW population already possesses physiological and morphological adaptations due to the extreme conditions of pH and salinity. Although T. domingensis is not a halophyte species and does not possess anatomical structures to tolerate and excrete salts, it is capable of modifying its morphology in order to adapt to extreme conditions, such as the exposition to an industrial effluent. These results denote that a suitable acclimation is necessary to favour the adaptability of T. domingensis to survive in saline environments.