关键词: 中熟粳稻, 超高产, 生长发育, 调控途径

Abstract: 【Objective】Rice is one of the most important food crops in China. The realization of its super-high-yielding has a great significance for food security of the country. This study investigated the growth and development characteristics of the super-high-yielding (grain yield >11 t·ha-1) of rice.【Method】Four mid-season japonica rice cultivars (including lines), Lianjiajing 2, Huajing 5, 0026 and 9823, were grown in a paddy field. Growth analysis was performed during the growth period, and yield and yield components were determined at maturity.【Result】Super-high-yielding rice had more sipkelets per panicle and higher filled-grain percentage than the high-yielding rice (CK, grain yield 8.98～9.16 t·ha-1). There was no significant difference in 1000-grain weight between the super-high-yielding and the CK. Super-high-yield rice exhibited fewer tillers at the early growth stage (from transplanting to jointing), while a higher ratio of productive tillers to total tillers, as compared with the CK. The leaf area index, photosynthetic potential and dry matter accumulation of the super-high-yielding rice were lower than those of the CK at the early growth stage, and their differences were not significant between the two rice types at heading, and were greater for the former than the later after heading. The root-shoot ratio at each growth stage, root bleedings from heading to maturity, grain-leaf ratio, translocation percentage of the matter from stems and sheaths and harvest index of super-high-yielding rice were greater than those of CK. 【Conclusion】 The indexes for the growth and development of super-high-yielding mid-season rice population were suggested, i. e., total spikelets > 4.5 × 104·m-2, filled-grain percentage > 90%, 1000-grain weight > 26 g; ratio of productive tillers > 80%, leaf area index at heading 7.5-8.0, photosynthetic potential during whole growth period > 5×106 m2·d·ha-1, total dry matter weight at maturity >22 t·ha-1, harvest index > 0.51; grain-leaf ratio (No of spikelets per cm2 leaf area) > 0.58; root-shoot ratio at heading stage >0.25 and the amount of root exudates > 5 g·m-2·h-1. The regulation approaches and key cultivation techniques for raising the super-high-yielding population were discussed.

Key words: Mid-season japonica rice, Super-high-yielding, Growth and development, Regulation approach