| A field experiment with two factors was carried out at the Rice Research station in Al-Mishkab during 2008 and 2009 seasons to study the effect of seedling age on yield of some rice cultivars.The design was split plot with RCBD arrangement in four replicates. The statistical analysis showed that the early seedlings ages i.e.(20 and 27)day led to a significant increase in number of panicles/m2 , number of grains/ panicle , paddy yield compared with two late ages (34 and 41) days, Treatment of seedling ages (20 and 27) gave highest value than other treatments ,at number of panicles/m2 (214.9 , 221.7) panicle in first season , (237.1 , 220.9) panicle in second season , number of grains/ panicle (164.0 , 167.8) grains in first season , (153.8 , 158.3) grains in second season, paddy yield (4.833 , 4.945)t.ha-1 in first season , (4.340 , 4.290) t.ha-1 in second season respectively . However a significant reduction of sterility percentage (11.65 , 11.69) in first season ,and (7.79 , 8.30) in second season respectively, was found in these two early ages .Seedlings ages had no significant effect on, weight of 1000 grain and harvest index in both seasons. Cultivars showed significant differences in most studied characters. local cultivar Anber33 gave highest values paddy yield (4.759 t.ha-1) due to its highest number of grains/panicle(192.3). While fourat1 was superior in paddy yield.hectare-1(4.526 t.ha-1) due to its highest number of panicles(208.8). m2, weight of 1000 grains(23.66) gm in first season while in the second season , Cultivars showed not significant differences in paddy yield . It could be concluded that seedlings transplanted in the ages of (20 and 27) day gave highest paddy yield due to the increases in the yield components |