Influence of NaCl Salinity on Growth and Metabolic Status of Protein and Amino Acids in Rice Seedlings

Abstract Seeds of four rice cultivars differing in salt tolerance when grown under increasing level of NaCl salinity and seedling vigour as well as metabolic status of total and soluble proteins, amino acids were evaluated in seedlings at increasing days of growth it was observed that increasing level of salinity caused loss in dry wt. of seedlings as well as reduction in lengths of root and shoot. In both sets of cultivars salt stressed seedlings showed higher levels of total as well as soluble proteins, total amino acids compared to non salinized seedlings. In roots of salt susceptible cvs. Ratna and Jaya increased salinity up to 14 mmhos/cm remarkably increased total as well as soluble protein level whereas in shoots moderate level of salinity increased protein level compared to controls and higher salinity level caused suppression in such increase. Tolerant cultivars always maintained higher levels of total as well as soluble proteins and total amino acids in salt stressed seedlings compared to susceptibles. Amino acids which accumulated greatly in salinized seedlings were arginine, phenylalanine, alanine, leucine, proline, valine and glutamine. Results suggest possible role of proteins and amino acids in confering salt tolerance in rice.