Study of growth and antioxidant enzymes in Andrographis paniculata (Burm f.) wall ex nees. as influenced by salinity and alkalinity

An attempt was made to study the influence of salinity (100mM, 150mM, 200mM and 250mM NaCl) and alkalinity (50mM, 100mM, 150mM and 200mM NaHCO₃) on Plant height, Number of Leaves, Leaf Area, Relative Water Content, Catalase and Peroxidase activity of Andrographis paniculata. Untreated plants were kept as control. The plant samples were analyzed for 100 DAS at every 20 days interval. The results indicated that the reduction in growth parameters were abrupt in Andrographis and decreased in above mentioned growth parameters at high salt concentrations (250mM NaCl and 200mM NaHCO₃) were observed. Similarly, alteration in the antioxidant enzymes viz. catalase(CAT) and peroxidase (POD) activity was observed in all the treatment. The maximum increment in CAT and POD activity was recorded at 200mM NaCl and 150mM NaHCO_3. The results revealed that the extent of alkaline stress induced changes was higher than saline stress and alkaline conditions impose more deleterious effect on Andrographis plant.

Andrographis paniculata is an important medicinal plant belongs to family Acanthaceae commonly called “King of Bitters” or “Kalmegh”.

Salinity and Alkalinity both decreased the growth of Andrographis parallels to increasing concentrations. However, the maximum reduction in growth was observed under alkalinity as compared to salinity.

An increment in Antioxidative enzymes viz. CAT and POD was observed under both saline and alkaline stress. The maximum increment in CAT and POD activity was recorded at 200mM NaCl and 150mM NaHCO₃. However, at high level of salt concentrations (250 mM of NaCl and 200 mM NaHCO₃) it was significantly decreased.