关键词: “四特”晚籼稻, 秧龄, 播种期, 产量

Abstract: The “four special”late indica rice series combinations has short heading date,poor elasticity of seedling age,and easy to early spike when the seedling age was long,so the yield advantage was difficult to give full play.In order to prevent early ear of “four special”late Indica rice series combinations in production,experiments were carried out with different seedling age and sowing date using three “four special”late Indica rice combinations.The results showed that the highest yield was found in the treatment with 20-day-old seedling age.The most effective panicles per unit area was found in the treatment with 15-day-old seedling age,which was not significantly different with 20-day-old seedling age and 25-day-old seedling age,but significantly higher than 35-day-old seedling age(P<0.05).The seed setting rate and 1 000-grain weight had no significant difference between 30-day-old seedling age and 35-day-old seedling age,but most were significantly lower than 15-day-old seedling age and 20-day-old seedling age(P<0.05).The early ear had already occurred when the seedling age reached 25 days,and was serious when the seedling age more than 30 days.The suitable transplanting seedling age was 15 to 25 days and the most suitable transplanting seedling age was 20 days for “four special”late Indica rice series combinations.According to the safe full-ear and maturity date and the accumulated temperature required for growth period,the sowing of “four special”late Indica rice series combinations could be delayed until June 30 to shorten the seedling age and minimize the effect of seedling age on yield.

Key words: “four special” late Indica rice, seedling age, sowing date, yield