Maximisation of seed production by aditionaJ dose of N and K in hybrid rice

摘要

Parental lines (A and R lines) of rice hybrids ADTRH land 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 kgK each atPI 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 Nand 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.