Abstract

                                An investigation was carried out during Kharif season of 2014-15 at Department of Rice, Tamil Nadu Agricultural University, Coimbatore-3 to study the influence of sowing dates on phenology and yield traits of some rice genotypes. Among the three sowing dates (9th June, 23rd June and 7th July) and twelve rice genotypes were used in this study revealed that, rice genotypes sown on 9th June and the long duration rice genotype (CB-05-022) consumed more number of days to reach different growth stages viz., active tillering, panicle initiation, 50 per cent flowering and physiological maturity stages 42, 87, 126, 141 days where it took longer vegetative growth duration to produce more productive tillers and provided higher grain yield. The GDD (Growing Degree Day) was accumulated more in rice genotypes sown on June 9th at active tillering, panicle initiation, 50 per cent flowering and physiological maturity stages where it can efficiently utilize the available natural resources for its growth and development. The maximum grain yield of 9764 kg ha-1 was registered by the genotype CB-05-022 sown on 9th June with an increase of 16.4 per cent over other sowing dates. To conclude, sowing date (9th June) favoured better growth and yield in rice genotypes and the long duration genotype, (CB-05-022) showed desired phenological characters which utilize heat units efficiently under favourable environment to provide better yield than other genotypes used.

Key words : Rice, Phenology, Growing degree days, Yield