Optimized Management Practices Synergistically Improved Grain Yield and Nitrogen Use Efficiency by Enhancing Post-Heading Carbon and Nitrogen Metabolism in Super Hybrid Rice

• 全文链接

优化管理实践通过提高超级杂交稻抽穗后碳氮代谢协同提高籽粒产量和氮素利用效率

关键词：

来源：

Agronomy

全文链接：

//agri.nais.net.cn/topic/downloadFile/e6863998-e4f9-41bc-a18c-722c4992b1b6

来源地址：

//agri.nais.net.cn/topic/downloadFile/e6863998-e4f9-41bc-a18c-722c4992b1b6

资源所属：

杂交水稻专题

类型：

学术文献

语种：

英语

原文发布日期：

2022-12-21

摘要：

The super hybrid rice breeding program in China has raised genetic yield ceilings through morphological improvements and inter-subspecific heterosis. Despite this, little information on the physiological basis underlying this yield transformation exists, and less so on the genotype x environment x management conditions enabling consistent yield gains. Here, we assess grain yield, photosynthetic physiology, and leaf carbon and nitrogen (N) metabolic properties of super rice (Y-liangyou900) under four management practices (i.e., zero-fertilizer control, CK; farmers’ practice, FP; high-yield and high-efficiency management, OPT1; and super-high-yield management, OPT2) using a field experiment conducted over five years. Grain yield and agronomic N use efficiency (AEN) of OPT2 were 15% and 10% higher than OPT1, and 30% and 78% higher than FP, respectively. The superior yields of OPT2 were attributed to higher source production capacity, that is, higher leaf photosynthetic rate, carbon metabolic enzyme activity (i.e., AGP and SPS), nitrogen metabolic enzyme activity (i.e., NR, GS, and GOGAT), soluble protein and sugar content, and delayed leaf senescence (the latter due to elevated activity of protective enzyme systems) during grain filling. The higher AEN of OPT2 was associated with higher activity of leaf carbon metabolic enzyme (i.e., AGP and SPS), nitrogen metabolic enzyme (i.e., NR, GS, GDH, and GOGAT) and protective enzyme (POD) after heading, and lower C/N ratio in grains. We conclude that optimized management (optimized water and fertilizer management with appropriate dense planting) improved grain yield and N use efficiency simultaneously by enhancing post-heading leaf carbon and N metabolism and delayed leaf senescence.