Vol. 12, Issue 8 (2023)

Author(s):
Hari Narayan, Tapas Chaudhary, Sangita Kumari, Ravindra Soni and Upendra Kumar

Abstract:
Salinity is one of the most serious problems to agricultural productivity. The aquatic fern Azolla is used as an effective bio-inoculant in rice paddy production. Result indicated that two species of Azolla chosen based on survivability which is A. microphylla (salt-tolerant) and A. rubra (salt-sensitive) in 80 mM NaCl. Although using standard screening protocol is better than hydroponics condition due to its provide natural condition for screening of Azolla plant. Although the DT was lower in A. microphylla, under salt stress (80 mM NaCl) the total biomass increased as characterized by RFC, RGR, DW and ARL in comparisons with A. rubra which had comparatively higher DT. Similarly, the MC reduced sharply with rise in salt concentration in A. rubra. Under salt stress condition soil pH and EC was reduces by Azolla plant but highly reduces by A. microphylla contrast A. rubra. After 15 days, reductions in chl a and b and carotenoid contents were found to be associated with both the strains, however with rise in salt concentrations, significant increase in anthocyanin content was observed in both the strains. The concentrations of antioxidant enzymes such as SOD, APX, CAT and proline and depicting the antioxidant mechanisms in this species play major role for salt tolerance. MDA content was increased with rise in salt concentration in both strain of Azolla. Presence of NaCl in the nutrient medium Na+ and Ca2+ increased in plant cell at different salt stress, while it reduced the cellular K+ level in both species when rise salt concentration.