Salinity tolerance in rice varieties at different growth stages

Abstract

The salt tolerance of several Australian and overseas rice varieties was studied at germination, early vegetative growth, and reproductive development in a temperature controlled glasshouse to determine the reliability of screening at any particular stage. At all 3 stages, varieties differed in their degree of tolerance, but the order of tolerance varied considerably between stages. Of the varieties used, the Australian long grain variety Pelde was tolerant for germination but most intolerant during early vegetative growth and reproductive development. The Japanese variety Somewake was intolerant during germination and vegetative growth but most tolerant during reproductive development. Linear regressions showed inverse relationships (r2 = 0.97-0.73) between sodium concentration in the shoots during early growth and shoot dry weight for most varieties. For Pelde, dry matter production was most closely related to potassium concentration in the shoots (r2 = 0.92).