Can optimizing seeding rate and planting density alleviate the yield loss of double‐season rice caused by prolonged seedling age?

Abstract

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.

Evaluation of agro-morphological and molecular characters of 22 rice landraces of East Timor

“…Other factors affecting the number of tillers were planting distance, growing season, and the use of fertilizers. Wide planting, supported by a good environment, will increase the number of tillers (Asmamaw 2015;Huang et al 2021). The grains' length ranged from 6.42-9.86 mm (CV=12.73%), and Ale kalaha dikar has the longest grain of 9.86 mm and Hare mean 14, the shortest of 6.42 mm.…”

Delayed Sowing under the Same Transplanting Date Shortened the Growth Period of Machine-Transplanted Early-Season Rice with No Significant Yield Reduction Caused

“…At the same time, the adverse effects of prolonged seedling age are also worthy of attention. A long seedling period not only leads to the deterioration of seedling quality but also inhibits plant growth and yield formation after transplanting [18]. Moreover, studies have indicated that when the seedling age exceeds 40 days, it can result in premature heading, affecting the double-cropping rice yield [19].…”