Mineral nutrient analysis of three halophytic grasses under sodic and saline stress conditions

Present study was carried out to assess the effects of soil salinity/sodicity on mineral nutrient status of Urochondra setulosa, Leptochloa fusca and Sporobolus marginatus at ICAR- Central Soil Salinity Research Institute, Karnal, Haryana during 2016-19. Treatments of salinity/sodicity (pH similar to 9.5, pH similar to 10, ECe similar to 30 dS/m, ECe similar to 40 dS/m and ECe similar to 50 dS/m) were created in microplots (2.5 m x 1.5 m x 0.5 m) using saline/sodic water. Na+ and Cl- content (% DW) significantly increased with increasing sodicity/salinity stress condition in all three grass halophytes, whereas K+ content decreased. These grass halophytic species showed relatively less reduction in Ca, Mg and Fe contents up to sodic stress of pH similar to 9.5 and salinity level of ECe similar to 40 dS/m. Zn, Cu and Mn content decreased with increasing stress conditions but higher decrease was observed under sodic stress. The Na+/K+ and Na+/Ca2+ ratio was considered as indicators for measuring salt tolerance in plants. Na+/K+ ratio increased with increasing stress condition in all the three grasses but Leptachloa maintained their Na+/K+ near pH 1.0 under sodic stress condition and also maintained their Na+/Ca2+ below 1.0 up to pH - 9.5 and ECe similar to 40 dS/m. Higher sodic stress of pH-10.0 caused significant increase in Na+/Ca2+ in Urochondra and Sporobolus, whereas under highest salinity level, Leptachloa showed highest value for Na+/Ca2+. Changes in the accumulation patterns of nutrient in response to salinity is an important aspect and study showed highest positive correlation between Ca - Mg & Zn and negative between Na - Ca and K.