Effect of NaCl salinity on RNA and RNase were determined in endosperms and embryoaxes at increasing hours of germination in salt sensitive Ratna, Jaya and tolerant CSR-1, CSR-3 rice varieties. In sensitive cultivars increased salinity level caused increase in endospermic RNA whereas in tolerants moderate salinity i.e. 7 dSm-1 did not bring about any alteration in RNA level. In embryoaxes of sensitive cultivars RNA level decreased during 48-120h of germination whereas in tolerants it increased during this period. Salt tolerant cultivars maintained higher RNase activity than sensitives. Unlike endosperms in embryoaxes salinity caused increase in RNase activity with greater increase in sensitive cultivars over tolerants. Two RNase isoenzymes were detected in germinating seeds and seedlings of sensitive cultivars and 3 in tolerants. Results suggest possible roles of RNA and RNase in relation to salt tolerance in rice.
