Shandong Rice Research Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China.
Sci Rep. 2017 Oct 26;7(1):14072. doi: 10.1038/s41598-017-14672-7.
Delayed transplantation frequently occurs in mechanically transplanted rice in China, leading to a significant reduction in grain yield. Thus, determining how to compensate grain yield loss is crucial for improving rice cultivation technology. A field experiment was conducted to investigate the effects of cultivation density and seedling age on agronomic traits and grain yield of mechanically transplanted rice. With increasing seedling age, rice tiller number, pre-anthesis dry matter accumulation, remobilization efficiency and contribution to grain yield, as well as post-anthesis photosynthesis amount decreased, causing reductions in the number of effective panicles, the total number of grains per panicle, the sink capacity per tiller, and grain yield. In rice transplanted at 30- and 35-day seedling ages, increasing cultivation density significantly enhanced the number of effective panicles and grain yield. Additionally, there existed strong, positive correlations between sink capacity per tiller and pre-anthesis dry matter remobilization efficiency and pre-anthesis dry matter contribution to grain yield. We conclude that in addition to cultivation density, enhancing the amount of pre-anthesis dry matter and the remobilization efficiency could be feasible for mitigating grain yield loss caused by delayed transplantation.
在中国，机械移栽的水稻经常会出现移栽延迟的情况，导致稻谷产量显著下降。因此，确定如何弥补稻谷产量损失对于提高水稻种植技术至关重要。本田间试验研究了种植密度和秧龄对机械移栽水稻农艺性状和稻谷产量的影响。随着秧龄的增加，水稻分蘖数、开花前干物质积累量、再生产力效率及其对稻谷产量的贡献以及开花后的光合作用量均降低，从而导致有效穗数、每穗粒数、每穗分蘗的库容量以及稻谷产量减少。在 30 天和 35 天秧龄的水稻移栽中，增加种植密度显著提高了有效穗数和稻谷产量。此外，每穗分蘗的库容量与开花前干物质再生产力效率以及开花前干物质对稻谷产量的贡献之间存在很强的正相关关系。我们的结论是，除了种植密度外，增加开花前干物质的量和再生产力效率可能是减轻移栽延迟导致的稻谷产量损失的可行方法。
