Parental lines (A and R lines) of rice hybrids ADTRH 1and CORH 2 were given four fertilizer dose treatments and the results indicated that the application of recommended dose of fertilizer (RDF) @ 150:60:60 kg NPK ha^-1, + 25 kg N and 15 kg K each at PI and 10 days after PI increased the plant height, total tillers, productive tillers and seed weight of both A and R lines. This additional fertilizer dose advanced the days to 50 per cent flowering, improved the panicle exsertion and seed set in A line. Though, there was a progressive increase in most of the growth traits due to progressive increase in fertilizer dose, the stage of application was most critical and specific to certain growth traits. This additional N and K dose exerted an increase of 13.7 and 12.3 per cent hybrid seed yield in ADTRH 1 (2,061 kg ha^-1) and CORH 2 (1,663 kg ha^-1) respectively. The increase in grain yield was 15.0 and 11.5 per cent in R lines of ADTRH 1 (1,623 kg ha^-1) and CORH 2 (1,488 kg ha^-1) respectively.