Vol. 12, Issue 12 (2023)

Author(s):
Akshara Balachandra, Varanavasiappan Shanmugam, Kumar K Krish, Ravichandran Veerasamy, Kokiladevi Easwaran, Sudhakar Duraialagaraja and Arul Loganathan

Abstract:
Salinity is one of the major abiotic stressors limiting the growth and productivity of crops like rice. Salt stress is due to a higher proportion of sodium ions entering the plants. Excessive sodium ions in soil competes with potassium, the counter ion, affecting the intracellular Na/K ratio which is a vital indicator of plant’s salt tolerant capacity. The Na⁺ and K⁺ concentrations in roots of salt tolerant genotypes (Pokkali and Kuthiru) and salt susceptible elite rice cultivars (ASD16 and IR64) were analysed during the late vegetative stage. A low Na/K ratio in roots of Pokkali and Kuthiru as compared to the salt susceptible genotypes clearly differentiated the salt tolerant and susceptible genotypes. Besides, other physiological parameters such as relative water content, chlorophyll stability index, root and shoot length, root and shoot dry weight also fell in favour of the salt tolerant genotypes. Therefore, understanding the morpho-physiological parameters can help in evaluating the salt stress tolerance ability of rice genotypes.