This research work was carried out at Pindamonhangaba Experimental Station - Instituto Agronômico - State of São Paulo - Brazil, aiming to evaluate several transplanting seedling ages on subsequent rice development. In the 91/92 and 92/93 growing seasons six seedling ages (25, 32, 39, 46, 53 and 60 days after emergence) were tested in four rice cultivars (IAC-4440, IAC 100, IAC 101 and IAC 102) while in the 93/94 growing season IAC 100, IAC 101 and IAC 102 cultivars had their plant cycles checked by using 21, 28, 35, 42, 49 and 56 day-old seedlings. In general, the older the seedlings at the transplanting stage, the longer the flowering cycles. Also thirty-five day and older seedlings caused reduced rice grain yields as compared to earlier ones; the best yield results were achieved with the use of 28 day-old seedlings. IAC 102 revealed to be the less affected of all rice cultivars tested as to the several seedling ages used.
rice; cultivars; seedling ages; transplanting