Abstract

                                A pot culture experiment was conducted at Agricultural College and Research Institute, Trichy during 1998 to 1999 with three levels of salinity viz. EC < 1, 1-4, > 4 dSm with four rice varieties viz. TRY1 and Co43. (Tolerant) and IR20 and ADT 39 (susceptible) to find out the effect of soil salinity on certain enzymatic activities, physiological attributes and yield. Growth and yield reductions were more at EC 4 dSm' than other treatments. Leaf soluble protein and chlorophyll content at flowering decreased with salinity and the reduction was more in the susceptible varieties than the resistant varieties. Proline content was increased with level of salinity and was higher in tolerant than the susceptible varieties. Amylase and ATPase activities increased toward salainity. Nitrate reductase activity was stimulated more at high salinity level in tolerant varieties than the susceptible varieties.

Key words : Salt tolerance, Rice, ATPase, NRase, Soluble protein and Proline content