| Rice is one of the most important food crops in China. The realization of its super-high-yielding (SHY) has great significance in ensuring food security and society stability. The elucidation of the characteristics of population and nutrient absorption plays an important role in realization of SHY. This study investigated the population characteristics, nutrient absorption and key cultivation techniques. The main results are as follows:1. Population Characteristics of SHY rice Super-high-yielding rice (grain yield>12 t hm-2) had more spikelets per panicle and higher filled-grain percentage than the high-yielding rice (grain yield 8～9t hm-2, CK). There was no significant difference in 1000-grain weight between the SHY and the CK. SHY rice exhibited fewer tillers at the early growth stage (from transplanting to jointing), while a higher ratio of productive tillers to total tillers, when compared with the CK. The leaf area index,photosynthetic potential and dry matter accumulation were lower for the SHY rice than those for the CK at the early growth stage, and their differences were not significant between the two 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, and translocation percentage of the matter from stems and sheaths, and harvest index of SHY rice were greater than those of CK. The leaf area index (LAI), chlorophyll content (SPAD value), photosynthetic rate (Pr) and PS II electron transport efficiency (Fv/Fm) of SHY rice were greater than those of CK, while nonphotochemical quenching coefficient (qN) was lower than that of CK. The indexes for the growth and development of SHY (grain yield > 12 t hm-2) mid-season rice population were suggested, i. e, total spikelets > 5.2×104 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 the whole growth period > 5×106 m2 d hm-2, total dry matter weight at maturity > 22 t hm-2, harvest index > 0.50, grain-leaf ratio (No. of spikelets per cm2 leaf area) > 0.58, root-shoot ratio at heading > 0.25, and amount of root exudates > 5 g m-2 h-1.2. Characteristics of nutrient absorption and accumulation for SHY rice Compared with high-yielding cultivation (CK), plants of SHY rice absorbed and accumulated less nitrogen (N) before the critical stage of productive tillers and more N after the jointing stage, especially at later growth stages. There was no significant difference in potassium (K) absorption and accumulation between the SHY and the CK before the critical stage of productive tillers, whereas SHY plants absorbed more K than in the CK from jointing to maturity. The amount absorbed of N, P, and K for producing 1000 kg grains was 21.6～21.9 kg,6.7～7.2 kg, and 24.8～25.6 kg, respectively, in SHY rice,and 23.8～24.3 kg,6.8～7.3 kg,and 27.4～29.0 kg,respectively,in the CK.3.Cultivation approaches and techniques for SHY Rice The main approaches to realizing super-high-yielding of rice included enlarging sink size through stabling panicle number and increasing spikelets per panicle, improving population quality through increasing the percentage of productive tillers and grain-leaf ratio, enhancing sink (grain) strength through increasing sugar-spikelet ratio or sugar-grain ratio, increasing matter production capacity through fostering a healthy and strong root system during the grain filling period, and increasing harvest index through enhancing remobilization of assimilates from vegetative tissues to grains. The key techniques were nursing strong-seedlings, site-specific nutrient management, precise and quantitative water-saving irrigation.
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