Prolonged seedling age (PS) caused by delayed transplanting frequently occurs in double-season rice (Oryza sativa L.), leading to a significant grain yield loss. However, it is not clear whether optimizing the seeding rate in the nursery and planting density in the field could compensate for this yield loss. Field experiments with two seedling age, two planting density, and two seeding rate treatments were conducted in the early and late growing seasons of 2013 and 2014 in Wuxue County, Hubei Province, China. Increasing the planting density significantly increased grain yield but couldn't completely alleviate the negative effect of PS on grain yield in both early and late growing seasons. Reducing the seeding rate in the nursery significantly increased the grain yield in both seedling age treatments in the late season with an average of 4.4% across treatments and years. There was a significant interaction effect between seedling age and seeding rate on grain yield in the early season, suggesting that yield loss could be significantly mitigated by reducing seeding rate. In conclusion, optimizing seeding rate and planting density could partially compensate for the yield loss caused by PS.

中文翻译：

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优化播种量和种植密度能否缓解双季稻延长苗龄造成的产量损失？

双季稻（Oryza sativaL.)，导致显着的粮食产量损失。然而，目前尚不清楚优化苗圃播种量和田间种植密度是否可以弥补这种产量损失。2013年和2014年生长期早、晚，在湖北省武雪县进行了2种苗龄、2种种植密度、2种播量处理的田间试验。增加种植密度显着提高了籽粒产量，但不能完全缓解PS对生长前期和后期籽粒产量的负面影响。降低苗圃播种率显着增加了晚季两种苗龄处理的谷物产量，处理和年份平均为 4.4%。苗龄和播种量之间对早季粮食产量有显着的交互作用，表明降低播种量可以显着减轻产量损失。总之，优化播种量和种植密度可以部分补偿PS造成的产量损失。