The relationship between dry matter production and yield, dynamics of dry matter accumulation and output and translocation in middle and last stages of three types of populations (High Yield: 8.25–9.75 t ha -1 ; Higher Yield: 9.75-11.25 t ha -1 ; Super High Yield:＞11.25 t ha -1 ) in four japonica super rice (Wujing 15, Huaidao 9, Xudao 3 and Changyou 1) were analyzed. The results showed that yield was significantly positively correlated with weight of dry matter at maturity and the dry matter accumulation from heading to maturity, there were parabolic relationships between yield and weight of dry matter at heading in high yield, higher yield and super-high yield populations. Weight of dry matter from jointing to heading was significantly positively correlated with yield from high yield population to higher yield population and from higher yield population to super-high yield population. Super-high yield population had more biomass at maturity than higher yield and high yield populations, and the harvest index was not significantly higher than that of higher yield population, but was significantly higher than that of high yield population. Weight of dry matter, LAI in heading, rate of leaf area of productive tillers, rate of leaf area from flag leaf to 3rd leaf, spikelets of population and spikelets per square centimeter leaf area in middle stage (from jointing to heading) were significantly higher than these of higher yield and high yield populations. Leaf area decreasing per day of super-high yield population from heading to maturity was significantly less than that of higher yield and high yield populations. Leaf area duration, crop growth rate, net assimilation rate, biomass and grain-leaf ratio (filled grains per square centimeter leaf area, grain weight per square centimeter leaf area) from heading to maturity were significantly higher than these of higher yield and high yield populations. Output and translocation of dry matter in super-high yield population from heading to milky stages were significantly higher than these of higher yield and high yield populations, while these from heading to maturity were significantly lower than these of higher yield and high yield populations. Weight per stem and sheath and total filling in maturity of super-high yield population were significantly higher than these of higher yield and high yield populations.

以超级粳稻品种武粳15、淮稻9号、徐稻3号和常优1号为材料，对高产(8.25~9.75 t hm -2 )、更高产(9.75~11.25 t hm -2 )和超高产(＞11.25 t hm -2 ) 3个产量等级群体的物质生产与产量的关系、干物质积累、输出与转运等方面进行了系统的比较研究。结果表明，4个超级稻品种成熟期、抽穗至成熟期的干物质重与产量呈极显著正相关，抽穗期干物质重均与产量呈抛物线关系，拔节至抽穗期的干物质重与产量呈极显著正相关(高产—更高产、更高产—超高产以及将3个产量等级综合起来)；从高产到更高产再到超高产，4个超级稻品种的生物学产量不断提高(差异显著)，而超高产群体的经济系数则与更高产水平相当(0.5000以上)，显著高于高产水平；较之更高产、高产群体，超高产群体在生育中期(拔节至抽穗期)干物质积累量大，抽穗期叶面积指数高、株型挺拔、群体质量优[有效叶面积率、高效叶面积率、总颖花量与颖花/叶(cm 2 )、基部节间粗、单茎茎鞘重均高]，在生育后期(抽穗至成熟期)，光合能力强(叶面积衰减率小，光合势、群体生长率、净同化率高)、干物质积累量高(占生物学产量的40.0%以上)、茎鞘物质的输出与转运协调[实粒/叶(cm 2 )、粒重(mg)/叶(cm 2 )均高]。

This study investigated the formation rule of super-high-yielding late japonica hybrid rice in the double-cropping rice area. Using Yongyou 8 as material in Shanggao of Jiangxi Province, we analyzed grain yield and its components and the population characteristics in three types of populations (medium yield: 8.25–9.75 t ha -1 , high yield: 9.75–10.50 t ha -1 ; super high yield: >10.50 t ha -1 ). Results showed that supper-high-yielding population had more panicle and spikelets per panicle than medium and high yielding population. There was no significant difference in filled-grain percentage and 1000-grain weight among the three populations. Supper-high-yielding population exhibited more tillers at the transplanting stage and achieved expected number of stems and tillers on time, maximum number of stems and tillers at jointing stage. Then, the number of population stems and tillers began to decrease stably, achieving an expected number again. At last, ratio of productive tillers to total tillers of supper-high-yielding population was about 78.0%, which was higher than that of medium and high yielding population. The leaf area index of supper-high-yielding population was lower than that of medium and high yielding population at the early growth stage, with the maximum leaf area index of about 8.0 at booting, and stably decreasing to above 3.5 at maturity. The photosynthetic potential of supper-high-yielding population was smaller at early stage and larger at middle and late stages, as compared with the medium and high yielding populations, which was above 300 × 10 4 m 2 d ha –1 from heading to maturity, and above 675 × 10 4 m 2 d ha –1 in total. The dry matter accumulation of super-high-yielding population was smaller before jointing, increased faster after jointing, and reached about 10.5 t ha –1 at heading and 19.0 t ha –1 at maturity, which was significantly higher than that of medium and high yielding populations. Its translocation ratio of output was above 14.0%. In the super-high-yielding population the weight of dry matter of root, root-shoot ratio at each growth stage, root bleedings, N content, N uptaking, and utilization were greater than those of the medium and high yielding populations. Based on the results of this study, we discussed the regulation approaches and key cultivation techniques for raising the super-high-yielding population.

本研究旨在明确传统双季晚籼稻地区双季杂交晚粳稻超高产产量构成及其群体特征，阐明双季杂交晚粳稻超高产形成规律。以 江西省上高县 6.77 hm 2 连片双季杂交晚粳稻高产攻关示范方为依托，选用杂交粳稻甬优 8 号为材料，对中产 (8.25~9.75 t hm -2 ) 、高产 (9.75~10.50 t hm -2 ) 和超高产 (>10.50 t hm -2 ) 3 个产量水平群体的产量构成及群体特征进行系统比较研究。结果表明，与中产、高产水平群体相比，超高产水平群体表现穗数足、穗型大、群体颖花量多 (50 000×10 4 hm −2 以上 ) 的显著特点，但结实率和千粒重略低，差异不显著；群体茎蘖动态上，群体起点较高，可及时够苗；够苗后增长平缓，高峰苗数量较少、下降平缓，成穗率高 (78.0% 左右 ) 。群体叶面积指数前期增长较缓，最大值出现在孕穗期，为 8.0 左右，此后下降缓慢，成熟期仍保持 3.5 以上；群体光合势生育前期较小，中、后期较大，抽穗至成熟期光合势为 300×10 4 m 2 d hm −2 以上，总光合势为 560×10 4 m 2 d hm −2 以上。拔节前干物质量积累速度较慢，拔节后积累速度较快，至抽穗期群体生物量为 10.5 t hm −2 左右，抽穗后积累量亦高，成熟期干物重达 19.0 t hm −2 左右，后期茎鞘物质转运率大于 14.0% 。超高产群体根量多、活力较强；植株吸氮能力强、成熟期氮素累积量高，氮素利用率 40% 以上。根据双季杂交晚粳稻超高产形成特征，我们探讨了培育双季晚粳稻超高产群体的关键栽培技术。

A field experiment was conducted using the representative indica-japonica hybrid rice Yongyou 11 , Yongyou 12, Yongyou 13, Yongyou 15, Yongyou 17 to compare between super-high and high yield populations formed by the regulation of cultivation measures. The results showed that the spikelets of the super-high yield population was higher than that of high yield population, with difference very significant, but the seed-setting rate and 1000-grain weight of the super-high yield population were lower than those of high yield population. The average spikeletsper panicle was significantly higher than that of high yield population, meanwhile the number of the primary and secondary branches and total grains were higher than those of high yield population, showing a significant or very significant difference. The dry matter accumulation of the super-high yield population was a little lower than that of the high yield population at the jointing stage, but higher at heading and maturity stages. From the critical leaf-age for productive tillers to jointing stage, the super-high yield population had a steady growth with less ineffective tillers and lower peak number of tillers after jointing stage, the super-high yield population had a steady decline in number of tillers and had higher productive tillers rate, leaf area index, photosynthetic potential and dry matter accumulation, compared with the high yield population. The super-high yield population had higher culm diameter and culm wall thickness in the basal first , second and third internodes, as well as higher bender moment and anti-broken strength, and lower lodging index than the high yield population.

以籼粳杂交稻有代表性的品种甬优 11 、甬优 12 、甬优 13 、甬优 15 、甬优 17 为试材 , 通过栽培措施的调控 , 形成超高产 ( 产量 ≥12.0 t hm -2 ) 和高产 (10.5 t hm -2 ≤ 产量＜ 12.0 t hm -2 ) 群体。比较研究其特征表明 , 与高产群体比，超高产群体的总颖花量极显著提高 , 而结实率和千粒重略降低；平均每穗粒数极显著提高 , 并且一、二次枝粳数以及粒数显著或极显著提高；拔节期的干物重略低 , 但抽穗期和成熟期的干物重均显著或极显著提高；其有效分蘖临界叶龄期至拔节期的生长平稳 , 无效分蘖发生少 , 高峰苗低 , 拔节期以后茎蘖数下降平缓 , 成穗率、叶面积指数、光合势、干物质积累量等均较高；基部第 1 、第 2 、第 3 节间的茎秆粗度和茎壁厚度及基部第 1 、第 2 、第 3 节间的弯曲力矩、抗折力均显著或极显著提高 , 且倒伏指数减小。

【Objective】In order to provide a scientific basis for high water-fertilizer use efficiency of rice, the objective of this experiment was to study the effects of water and nitrogen (N) management patterns on population quality and yield of hybrid rice.【Method】Gangyou 527, an elite indica threeline hybrid rice cultivar widely planted in rice production in China, was used, which has high grain yield, extensive adaptability, and pest-resistance with growth duration of 145-150 days from sowing to maturity. The experiment was conducted to optimize N application, understand how different combinations of water and N management affect population quality of hybrid rice and yield, and study the correlations of population quality index and grain yield. Three irrigation regimes including submerged irrigation (W1), controlled alternate irrigation (W2), and dry cultivation (W3) combined with four N application managements at 180 kg?hm-2 of total N conditions were designed in the study. The four N application ratios were applied on different splits: (a) 2 splits: 70% basal and 30% 7 d after transplanting (DAT) (N1), (b) 3 splits: 50% basal, 30% 7 DAT, and 20% panicle N-fertilizer according to different leaf ages when 4th leaves emerged from the top (N2), (c) 4 splits: 30% basal, 30% 7 DAT, 40% panicle N-fertilizer equally when 4th and 2nd leaves emerged from the top (N3), (d) 4 splits: 20% basal, 20% 7 DAT, 60% panicle N-fertilizer equally when 4th and 2nd leaves emerged from the top (N4), in addition, no N application (N0) was designed as control. 【Result】 The results showed that there was an obvious interaction between irrigation regime and N application on dry matter accumulation and leaf area index (LAI) at the mainly growth stages, grain-leaf ratio at heading stage, net photosynthetic rate and yield. Decomposition analysis of water and nitrogen interaction effects showed that appropriate increase of N application ratio of later stage or W2 treatment had a positive effect on yield, the N application treatments had significant differences, and ranked as N3＞N2＞N1, and N4 treatment or W3 treatment resulted in a negative effect of water-nitrogen interaction. Compared to irrigation regimes, the results of water and nitrogen interaction showed that W2 treatment promoted the efficiency of N fertilizer, and achieved the purpose of promoted fertilizer by water. W2 treatment with suitable treatment of N3 application (30% basal, 30% tillering, 40% panicle N-fertilizer equally at 4th and 2nd leaves emerged from the top) was the best model in this paper and referred as the water-nitrogen coupling model, which could control the number of rice tillering, improve the rate of tiller panicle, guarantee the appropriate LAI and grain-leaf ratio at filling stage, increase the efficient leaf area ratio and population light transmission rate, and thus improving photosynthetic capacity at filling stage and the accumulation of photosynthetic products, and on the premise of effective panicle and seed-setting rate, the yield increased significantly. However, the other combinations of irrigation regimes and N application managements resulted in weakened advantages, or even resulted in the negative effects of water-nitrogen interaction and decreased of grain yield. Especially, either W3 treatment or high N application ratio of later stage (N4 treatment) resulted in yield reduction, and aggravated negative effect of water-nitrogen interaction. According to yield performance under W3, the proper decrement of panicle N-fertilize ratios could ease the negative effect of water-nitrogen interaction to some extents, and suitable panicle N-fertilizer should account for 20%-40%. Under W1, however, on the basis of 40%-60% base tillering N fertilizer, panicle N-fertilizer should account for 40%-60%. Correlation analysis indicated that there existed significantly or highly significantly positive correlations (r=0.589*-0.978**) between index of population quality and yield under water-nitrogen interaction, especially had positive correlations between yield and increasing amount of dry matter at filling stage and decrement of population light transmission rate from full-heading stage to 20 days full-heading stage.【Conclusion】The results suggest that rice plant growth could be improved and high grain yield could be achieved through integrating and optimizing water-fertilizer regulating techniques in rice production. W2 and suitable N3 combined application was considered to be optimum under the experimental conditions, optimum N management pattern was also N3 for W1. However, under W3 treatment, the ratio of panicle N-fertilizer application should be decreased, and N management patterns (50% basal, 30% tillering, and 20% panicle N-fertilizer at 4th leaves emerged from the top) were considered to be optimum for W3.

【目的】研究水氮管理模式对杂交籼稻群体质量及产量的影响，为水稻水肥高效利用提供依据。【方法】以杂交籼稻冈优527为材料，通过淹灌（W1）、控制性交替灌溉（W2）和旱种（W3）3种灌水处理及4种氮肥运筹处理（基肥﹕分蘖肥﹕穗肥分别为7﹕3﹕0、5﹕3﹕2（穗肥于倒4叶龄期施入）、3﹕3﹕4（穗肥于倒4、2叶龄期分2次等量施入）、2﹕2﹕6（穗肥于倒4、2叶龄期分2次等量施入），分别记为N1、N2、N3、N4），并设置不施氮处理，记为N0，分析水氮管理模式对杂交籼稻群体质量和产量形成的影响，并探讨水氮互作下群体质量指标与产量间的关系。【结果】水与氮对水稻主要生育时期干物质累积、叶面积指数（LAI）、抽穗期粒叶比、剑叶净光合速率、群体透光率及产量均存在显著的互作效应。互作效应分解分析表明，适当的氮肥后移处理、W2处理对产量均表现为正效应，且氮肥运筹效应大小表现为：N3＞N2＞N1，氮肥后移比例过大至N4处理水平、W3处理均会加重灌水处理的负效应；而水氮的交互作用结果表明，W2处理相对于其他灌水处理能促进氮肥肥效，达到以水促肥的目的，且W2模式下氮肥后移量可占总施氮量的40%，与基肥﹕分蘖肥﹕穗肥（倒4、2叶龄期分2次等量施入）为3﹕3﹕4氮肥运筹模式（N3处理）相配套，其水氮交互正效应不同程度的高于其他处理，能及时对群体分蘖数进行调控，提高成穗率，保证抽穗期水稻适宜的LAI及粒叶比，适当降低了上3叶叶倾角，提高了高效叶面积率及保持了群体透光率，有利于提高结实期群体光合产物的积累，并在保证一定数量有效穗及结实率的前提下，显著提高穗粒数及千粒重，最终促进了产量的增加，为本试验条件下最佳的水氮耦合运筹方式。而其他各水氮处理出现交互优势减弱，甚至出现负效应，均不利于产量的提高；尤其W3处理和氮肥运筹的互作效应对产量的影响均为负值，且氮肥后移比例过重会导致负效应加重；本试验旱作模式下，结合产量表现，应减少氮肥的后移量，氮肥后移量可占总施氮量的20%—40%为宜，以缓解水氮互作下的负效应，而淹灌模式下，氮肥后移量可占总施氮量的40%—60%为宜。相关分析表明，水氮互作下各群体质量指标与产量间显著或极显著正相关（r=0.589*—0.978**），尤其以抽穗后群体干物质增加量、齐穗至齐穗后20 d群体透光率的减少量与产量相关性较高。【结论】本试验条件下，W2N3为最优的水氮调控模式，在一定程度上调节并优化水稻群体质量指标体系，提高稻谷产量，W1模式与N3氮肥运筹为宜，而W3模式下可适当减少氮肥的后移量以基肥﹕分蘖肥﹕穗肥（倒4叶龄期一次性施入）为5﹕3﹕2的氮肥运筹模式（N2处理）为宜。

A high quality of population is necessary to achieve high grain yield in rice, but little information is available on understanding how cultivation patterns affect population quality. In this study, two japonica hybrid rice cultivars Changyou 3 and Changyou 5 were grown in the field, with six cultivation patterns including no nitrogen application (0N), local high yielding cultivation (control), cultivation for high yielding and high efficiency(CHYHE), super high yielding cultivation (SHY), cultivation for super high yielding and high efficiency (SHYHE) and cultivation for high use efficiency of N （ HUEN ） . The results showed that, the average yields of two cultivars under SHY and SHYHE were 12.0 t ha -1 and 10.9 t ha -1 , respectively, and 41.6% and 29.1% higher than these of control. Compared with the control, the SHY and SHYHE also significantly increased percentage of productive tillers, biomass from heading to mature, efficient and high efficient leaf area, grain-leaf ratio, leaf photosynthetic rate and SPAD values after anthesis , root-shoot ratio, and root bleeding after heading. The results indicated that the population quality of rice could be improved and higher yield could be achieved through integrating and optimizing cultivation techniques in rice production.

以杂交粳稻常优 3 号和常优 5 号为材料，设置未施氮处理 (0N) 、当地高产栽培 ( 对照 ) 、高产高效栽培、超高产栽培、超高产高效栽培和氮肥高效利用栽培等 6 种不同栽培模式，并观察上述栽培模式对水稻产量和群体质量的影响。结果表明，两品种超高产栽培和超高产高效栽培的产量平均分别达 12.0 t hm -2 和 10.9 t hm -2 ，较当地常规高产栽培分别高出 41.6% 和 29.1% 。与当地常规高产栽培相比，超高产栽培和超高产高效栽培等 处理的茎蘖成穗率明显提高，抽穗至成熟期的干物质积累增加，有效叶面积和高效叶面积比率增加。上述两处理还提高了水稻粒叶比，改善了源库关系，并提高了剑叶的光合速率和叶绿素含量以及抽穗后的根冠比和根系伤流量。这些结果表明，通过栽培技术的集成与优化，可以改善水稻群体质量，获得更高产量。

【Objective】The characteristics of yield formation and population dynamics and mechanisms of high-yielding formation were identified in pot seedling of mechanical transplanting japonica rice.【Method】Twenty-four japonica rice cultivars which have different weights of single panicle were grown by unified high-yielding cultivation in 2010, and were divided into three panicle types by clustering analysis with average single panicle in maturity. Three panicle types of japonica rice cultivars including large panicle type (LPT, Yongyou 2640 and Yongyou 8) and medium panicle type (MPT, Wuyunjing 24 and Ningjing 3) and small panicle type (SPT, Huaidao 5 and Huaidao 10) were field-grown from 2011 to 2012 in Diaoyu town, Xinghua county, Jiangsu province, China. By setting carpet seedling of mechanical transplanting rice (CS) as CK, the yield and yield formation, number of population stem and tiller, leaf area index (LAI) and dry matter accumulation of pot seedling of mechanical transplanting rice (PS) were investigated, and high-yielding formation mechanisms of PS were also explored in respect of seedling quality, matter accumulation after transplanting, plant type, staged photosynthetic matter production, photosynthetic potential (PP), crop growing rate (CGR) and net assimilation rate (NAR), matter transport in stem and sheath and root activity. 【Result】 Yield was significantly or very significantly higher in PS than CS. The range of increased yield was 8.71%-11.11% in large panicle-type variety, medium panicle-type variety was 6.85%-7.89%, and small panicle-type variety was 5.30%-6.34%. The increased yield was mainly attributed to higher total spikelets in PS, which owning to sufficient panicle and expanding spikelets per panicle. Compared with CS, PS had earlier tiller, suitable peak seedling tillers, slower reducing rate of tillers after jointing, enough effective panicles and higher ratio of productive tillers to total tillers at maturity. Leaf area index and dry matter accumulation in PS was significantly higher at the critical stage for effective tiller and very significantly greater at and after booting stage, and higher 5.17%-11.00% and 5.36%-9.20% at maturity than CS. The mechanisms of high-yielding formation in PS was that: After transplanting, there had strong seedling, better population started quality, earlier seedling establishment, faster tiller, more tillers of low position and greater dry matter weight of aboveground and root; They formed higher photosynthetic efficiency and quality population at heading, which had tighter plant type, better canopy, bigger leaf area, higher specific leaf weight, stronger stem and sheath, greater grain-leaf ratio; At the late growing stage, there had stronger root activity, slower decreasing rate of leaf area, higher photosynthetic potential and crop growing rate and net assimilation rate, greater dry matter accumulation, more coordinated matter export and translocation of stem and sheath.【Conclusion】With better population started quality and earlier tiller, pot seedling of mechanical transplanting rice had obvious advantages, especially, higher photosynthetic matter production and greater dry matter accumulation at the middle and late growing stages, which the yield formation characteristics were sufficient panicle, larger panicle type and more spikelets per panicle

【目的】旨在阐明钵苗机插水稻产量构成特征和群体动态特征以及高产形成机制。【方法】2010年选用24个不同单穗重粳稻品种统一高产栽培，以成熟期平均单穗重聚类分析划分3种穗型，并每种穗型筛选2个具有代表性品种。2011—2012年采用大穗型品种甬优8号和甬优2640，中穗型品种武运粳24号和宁粳3号，小穗型品种淮稻5号和淮稻10号为试验材料，在江苏省兴化市钓鱼镇进行大田试验，以毯苗机插水稻为对照，系统研究钵苗机插水稻产量及其产量构成、群体茎蘖动态、叶面积指数动态和干物质积累动态特征，并从秧苗素质、栽后物质积累、阶段光合物质生产、光合势、群体生长率、净同化率、株型特征、茎鞘物质输出与转运、根系活力等方面深入探讨钵苗机插水稻高产形成机制。【结果】钵苗机插水稻产量显著或极显著高于对照，大穗型品种增产8.71%—11.11%，中穗型品种增产6.85%—7.89%，小穗型品种增产5.30%—6.34%。钵苗机插水稻产量的提高主要原因是在足够穗数的基础上，显著或极显著增加每穗粒数，进而提高群体颖花量，同时保持稳定的结实率和千粒重。与对照相比，钵苗机插水稻群体茎蘖数栽后增长快，高峰苗适宜，拔节后群体茎蘖数消减缓慢，最终有效穗数足，成穗率高；群体叶面积指数和干物质积累量，有效分蘖临界叶龄期钵苗机插水稻显著高于对照，拔节期两者相当，孕穗后钵苗机插水稻显著或极显著高于对照，成熟期叶面积指数钵苗机插水稻较对照高出5.17%—11.00%，干物质积累量钵苗机插水稻较对照高出5.36%—9.20%。钵苗机插水稻高产形成机制为带土带蘖栽插，秧苗素质高，群体起点质量优，活棵早，分蘖快，低位分蘖多，栽后地上和地下部物质积累多，为争足穗、促壮秆和攻大穗奠定生物学基础；抽穗期株型紧凑，叶系配置优，叶面积大，比叶重高，基部茎秆粗壮，粒叶比高，形成高光效高质量群体；生育后期根系活力强，叶面积衰减慢，光合势大，群体生长率和净同化率高，干物质积累多，灌浆充实量大，茎鞘物质输出与转运合理。【结论】钵苗机插水稻群体起点质量高，栽后分蘖早生发快，群体生长优势明显，特别是生育中后期光合生产能力强，物质积累多。钵苗机插水稻产量构成特征表现为“穗数足、穗型大、粒数多”。

【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.

【目的】水稻是中国最重要的粮食作物，实现水稻超高产对保证国家粮食安全有重要作用。本研究旨在探讨超高产水稻（产量>11 t·ha-1）的生长发育特性。【方法】4个中熟粳稻品种（含品系）连嘉粳2号、华粳5号、0026和9823种植于大田，对其物质生产和产量形成进行了观察分析。【结果】与高产水稻（CK，产量为8.98～9.16 t·ha-1）相比，超高产水稻每穗颖花数多，结实率高，千粒重与CK无显著差异；超高产水稻移栽至拔节期的茎蘖数较CK少，但分蘖成穗率较高；超高产水稻的叶面积指数、光合势和干物质积累，生育前期较CK低，抽穗期与CK无显著差异，抽穗后则显著高于CK。超高产水稻各生育时期的根冠比、抽穗至成熟的根系伤流量以及粒叶比、茎鞘物质运转率和收获指数均显著高于CK。【结论】提出了中熟粳稻超高产群体的生育诊断指标：总颖花量>4.5万/m2，结实率>90%，千粒重>26 g；茎蘖成穗率>80%，抽穗期叶面积指数7.5～8.0，全生育期光合势>5×106 m2·d·ha-1，成熟期总干重>22 t·ha-1，收获指数>0.51；抽穗期粒叶比[颖花/叶(cm2)]>0.58，根冠比>0.25，根系伤流量>5 g·m-2·h-1。对培育超高产水稻群体的调控途径与关键栽培技术进行了讨论。

[Objective] The yield performance, the growth characteristics and the ecological adaptability of super hybrid rice were ascertained under different fertilizer application conditions in different tested sites. [Method] Field experiments with three fertilizer rate treatments (135, 180, 225 kg N/hm2) and two combinations (Zhunliangyou-527 and Liangyou-293) were conducted in ChangSha, GuiDong, HengYang, NanXian and YongZhou of Hunan province in 2004 and 2005. [Results] The significant differences of the dry matter accumulation, the harvest yield and its components were founded among the five tested sites and between two years, but no significant differences were founded among three fertilizer rate treatments. The yield components of super hybrid rice performed multifarious properties, of which the harvest yield showed the significantly positive correlations with the productive panicles, the grain filling percentage and 1000 grains weight, and the significantly negative correlation with grain number per panicle and no correlation with spikelet number per unit area. [Conclusion] The harvest yield of super hybrid rice was mainly influenced by the temperature and sunshine conditions of the tested sites and years. The fertilizer rate in the range from 135 kg N/hm2 to 225 kg N/hm2 was not the factor of harvest yield limited. And to increase panicle number was the possible path to increase harvest yield.

【目的】探明超级杂交稻在不同种植地点和不同施肥量条件下的产量表现及干物质生产特点。【方法】于2004～2005年在湖南省桂东、长沙、衡阳、南县和永州5个地点进行大田试验，按照N﹕P2O5﹕K2O为1﹕0.5﹕1的比例，设置3种施肥量处理（135、180、225 kg N•ha-1），田间采用随机区组排列，4次重复，以超级杂交稻组合准两优527和两优293为试验材料。【结果】超级杂交稻收获产量以桂东点产量最高，地点间差异显著，其中准两优527平均为7 492.3～12 209.2 kg•ha-1，两优293为6 984.0～11 679.5 kg•ha-1。产量构成因子和干物质生产量的地点间变化与收获产量一致，但在同一地点的不同施肥量处理间收获产量和干物质生产量差异均不显著。收获产量与单位面积穗数、结实率和千粒重表现为正相关，而与每穗粒数表现为负相关。【结论】超级杂交稻存在适宜的种植区域，且在施肥量为135～225 kg N•ha-1的范围内，施肥量不是超高产栽培的限制因子。超级杂交稻的库容量大，提高结实率和粒重是获得超高产的可能途径。

 In order to study the characteristics of super high yielding (yield ≥ 12.0 t ha -1 ) of mid-season indica hybrid rice cultivars in nutrition absorption, dry matter production and yield formation, we grew five rice cultivars (including lines), Yangliangyou 6, P88S/747, Luoyou 8, Luoyou 234 and Tianliangyou 2 in paddy fields. The leaf area index (LAI) at panicle initiation stage, heading stage and grain filling stage of super-high-yield rice was significantly higher than that of the high-yield rice (CK, Yangliangyou 6, grain yield ≥9.0 t ha -1 ), which was in the range of 6.5–7.2, 8.5–8.9, and 6.5–7.0, respectively. The ratio of high effective leaf area to total leaf area at the heading stage was higher than that of CK, which was in the range of 60.0%–66.5%. Super high yielding rice had more dry matter accumulation than CK at the heading stage, grain filling stage and maturity stage, which was in the range of 13.5–15.0, 15.0–16.0, and 25.0–28.0 t ha -1 , respectively. Super-high-yield rice did not show any advantage in the absorption of N, P and K at mid-tillering stage compared with CK, however, had noticeable advantage in that at panicle initiation stage, heading stage and maturity stage. Furthermore, super high yield rice had more productive panicles, higher seed setting rate and grain weight in comparison with CK, which were in the range of 250×10 4 –290×10 4 panicles per ha, 88.2%–92.3% and 29.0–31.0 g, respectively.

以5个杂交中籼稻品种(含品系)扬两优6号、P88S/747、珞优8号、珞优234和天两优2号为材料，研究大田条件下超高产水平(产量≥12.0 t hm -2 )的物质生产、产量构成及养分吸收特性。试验结果表明，与高产水稻(产量≥9.0 t hm -2 )相比，超高产水稻具有以下特征，幼穗分化期、齐穗期和灌浆结实期(齐穗后10 d) LAI大，分别为6.5~7.2、8.5~8.9和6.5~7.0；齐穗期的高效叶面积比率高，为60.0%~66.5%；齐穗期、灌浆期和成熟期积累较多的干物质，分别为13.5~15.0、15.0~16.0和25.0~28.0 t hm -2 ；分蘖盛期对氮(N)、磷(P)、钾(K)吸收利用优势不明显，而幼穗分化期、齐穗期和成熟期对N、P、K 吸收利用高而且积累速度快。此外，具有穗数多(有效穗数介于250×10 4 ~290×10 4 穗 hm -2 )、结实率高(88.2%~92.3%)、千粒重大(29.0~31.0 g)的特点。

以 18个不同穗重型籼稻品种为材料 ,研究了重穗型水稻的光合作用及物质运转。结果表明 ,重穗型水稻在齐穗后的剑叶净光合速率明显高于中、轻穗型品种。其机理是剑叶的Rubisco活性提高及叶绿素含量增加 ;有在高、低光强、高温和低CO2 浓度下对CO2 较强的同化能力的优势 ,光合“午休”现象较轻 ,能保持较高的净光合速率 ,显示其对环境有较强的适应性 ;气孔性状优良、气孔开度积 (单位面积气孔密度×气孔开度 )大 ,也是重穗型水稻净光合速率高的重要气孔因素。重穗型水稻抽穗后物质积累的优势明显 ,且茎鞘物质向穗部的转运量、转运率和转化率也远高于中、轻穗型品种。

【Objective】In order to research the mechanism of grain yield increase of rice by Quantitative Intensifying & Controlling Cultivation (RQICC, RP), which is a new cultivation for grain yield increase by less cost, in Yunnan Province, where there is an erect ecology, and divided into 6 environments for rice production. 【Method】 Field experiments were carried out in areas where the elevations are 750 and 2700 m above the sea level in Yunnan Province in 2008 and 2009. The contrast tests between RP and conventional cultivation of the main rice varieties, whose covering area was more than 1000 hm2 in the county, were carried out in six environments. The leaf age and tiller number were counted per week after transplanting. And the grain yield and its components were measured at mature stage. 【Result】 Grain yield increased by 16.0% and 15.8% for Indica and Japonica by RP in 2008, respectively, and by 18.3% and 15.3% in 2009, respectively. More spikelet per m2 was the main factor for grain yield increase as the number of panicle per m2 or number of spikelet per panicle increased by RP cultivation. And there was no difference in seed setting rate and grain weight between two cultivations. The crop population values of 12 t?hm-2 grain yield rice under different environments were listed. 【Conclusion】 Enough spikelet per m2 land was the base of high grain yield rice under different environments. This is a right way to increase grain yield by increasing spikelet number per m2, through increasing panicle-maximum tiller rate and using more nitrogen as panicle fertilize to initiate and keep more spikelet.

【目的】检验水稻定量促控栽培技术（RP）的适应性，并探索其增产机理。【方法】于2008—2009年在云南省6个生态区，以当地的主栽品种为材料，设置RP技术与常规栽培技术的对比试验，调查叶龄、茎蘖数、产量及其构成因素。【结果】在6个生态区RP技术显著增产，2008年籼、粳稻分别增产16.0%和15.8%；2009年分别增产18.3%和15.3%；与常规栽培技术相比，RP技术增加穗肥的用量促进了颖花的分化并降低了颖花的退化，从而促进大穗的形成，提高了穗粒数。【结论】RP技术通过降低基本苗和高峰苗提高茎蘖成穗率，获得更多的有效穗，通过重施穗肥促进大穗的形成，显著扩大库容量，最终获得高产。基于此提出了不同生态区12 t•hm-2水稻高产的群体指标。

【Objective】Rice yield is largely affected by many factors including environment and cultivation. Therefore, targeted use of cultivation techniques according to the climate characteristics can fully exploit the potential of rice yield and improve grain yield significantly. Experiments were conducted to study the effects of accurate fertilizer model (AF) on population quality and yield formation of hybrid indica rice cultivars in high mountain area. 【Method】 Field experiments were conducted in several rice growing areas(Huangping, Suiyang, Yuqing, Xingyi) of Guizhou province in 2010 and 2011. The local high-yielding potential hybrid indica cultivars were separately grown in every rice area, and the population quality and yield formation were studied through the comparison of accurate fertilizer model (AF) and conventional fertilizer model (CF). AF was designed based on Stanford equation, calculate the total N-fertilizer application based on three parameters including the nitrogen demand for the designed grain yield, nitrogen provided by soil, and N-fertilizer use efficiency(NUE). And the nitrogen applied at different growth stages were determined by nitrogen demand of corresponding stage. The total N fertilizer amount was divided into four sections and was applied 1 day before transplanting (30%), 7 days after transplanting (20%), panicle ignition (35%) and at the 2nd leaf from top stretching (15%), respectively. The total nitrogen application amount was identical for the two nitrogen ferltilizer models, and for the CF, nitrogen was applied 1 day before transplanting (20%), 7 days after transplanting (60%), panicle ignition (20%), respectively. Leaf area index (LAI) and dry matter production were measured at N-n, elongation, heading and maturity. Productive panicles, spikelets per panicle, filled grain ratio, grain weight were also measured at maturity.【Result】Compared with CF, AF increased average grain yield of rice by12.4%-48.0% in Huangping, Suiyang, Yuqing and Xingyi, spikelets per panicle increased by over 8.1%, seed-setting rate increased by over 2.5%, population spikelets amount increased by over 14.3%, but seed setting rate and 1000-grain weight was changed insignificantly. Judging from the panicle size, the percentage of small panicle (spikelets per panicle from 0 to 100) decreased by 36.7%-100%, the percentage of big panicle (spikelets per panicle from 100 to 250) increased by 2.2%-11.4%, and huge panicle (spikelets per panicle above 250) increased by 23.3%-94.9%. As for leaf area index (LAI), LAI at elongation stage of the AF rice was 4.2%-11.8% lower in comparison with CF rice. The LAI at heading stage increased by 4.2%-13.9% when LAI of top three leaves and spiklets per leaf area (total spikelets per leaf area, filled grain per leaf area, grain weight per leaf area) of AF rice compared with CF rice. The ratio of spikelet to leaf increased by 9.3%-132.7%, the ratio of grain to leaf increased by 12.8%-35.7%, and the ratio of grain weight to leaf increased by 10.1%-36.3%. The dry matter accumulation decreased at elongation, and increased by 9.8%-50.8% during the period from elongation to heading, and increased by 26.9%-62.7% during the period from heading to maturity.【Conclusion】 The AF management can increase the hybrid rice yield significantly, resulting from controlling the population growth before jointing, promoting group development after jointing, especially increasing LAI and dry matter accumulation in the period from heading to maturity, also including decreasing small panicle formation and developing large panicle.

【目的】水稻产量在很大程度上受环境、栽培技术等多种因素的影响。根据各地的气候特点有针对性地采用栽培技术，可以充分挖掘水稻产量潜力，大幅度提高单产。论文旨在探明精确定量施肥对贵州高原山区杂交籼稻群体质量及产量形成的影响效应。【方法】于2010—2011年在贵州省黄平、绥阳、余庆、兴义4个不同生态稻区，以当地具有高产潜力的杂交籼稻品种为试材，设计精确定量施肥模式（accurate fertilizer，AF）与常规施肥模式（conventional fertilizer，CF），通过对两种施肥模式的比较，研究不同施肥模式的群体质量及产量形成的差异。精确定量施肥模式以斯坦福（Stanford）方程为基础，根据目标产量需氮量、土壤供氮量及氮肥当季利用率计算总施氮量，各阶段的施肥量根据目标产量的阶段需氮量确定。精确施肥模式的总氮按照基肥﹕分蘖肥﹕促花肥﹕保花肥为30%﹕20%﹕35%﹕15%施用，常规施肥模式氮素总量按基肥﹕分蘖肥﹕促保花肥为20%﹕60%﹕20%施用。在有效分蘖临界叶龄期、拔节期、抽穗期、成熟期分别取地上部分测定叶面积和干物质量，成熟期考查穗数、穗粒数、结实率和千粒重。【结果】精确定量施肥模式显著提高了黄平、绥阳、余庆、兴义4个点的水稻产量，增产幅度为12.4%—48.0%，从产量构成因素看，穗数和穗粒数均较常规施肥模式有不同程度提高，穗数增加8.1%以上，穗粒数增加2.5%以上，群体颖花量增加14.3%以上，而结实率和千粒重两种施肥模式的差异较小；比较分析两种施肥模式的穗型大小，精确定量施肥模式较常规施肥模式穗粒数小于100粒的小穗比例降低、100—250粒的大穗和250粒以上的特大穗比例增加，小穗比例减少了36.7%—100%，大穗比例提高了2.2%—11.4%，特大穗比例提高了23.3%—94.9%；在叶面积指数与粒叶比方面；精确定量施肥模式比常规施肥模式的群体叶面积指数拔节前有所降低（4.2%—11.8%）、抽穗期显著提高（4.2%—13.9%）；粒叶比明显增大，其中颖花/叶为9.3%—32.7%、实粒/叶为12.8%—35.7%、粒重/叶为10.1%—36.3%；干物质积累量表现为精确定量施肥模式比常规施肥模式拔节前有所降低，拔节至抽穗期提高了9.8%—50.8%，抽穗至成熟期提高了26.9%—62.7%。【结论】精确定量施肥模式显著提高了贵州杂交籼稻产量，其途径主要通过控制拔节前的群体生长，促进拔节后的群体发展，适度减小拔节前群体叶面积和干物质积累，扩大拔节后尤其是抽穗后群体叶面积和干物质积累，在稳定提高穗数的基础上，控制晚生小穗数量、促进大穗形成，提高穗粒数和粒叶比，实现抽穗后群体干物质的高积累，从而获得高产。

针对贵州省已经实现的水稻12t/hm2超高产典型田块,在分析自然条件及主要栽培技术措施的基础上,着重阐述现有杂交稻组合高产个体,群体变化数量、质量及有关生理主要指标,根据这些指标,提出了贵州水稻育种目标是12.5～13t/hm2,实现这一目标的关键是拓宽遗传基础,利用优良基因资源,创造新种质、新材料,改良现有品种(组合)的株叶型结构及源--库--流关系,提高光能利用率.

Grain filling is the final growth stage in cereals when fertilized ovaries develop into caryopses. The degree and rate of grain filling in rice spikelets differ largely with their positions on a panicle. In general, earlier-flowering superior spikelets, usually located on apical primary branches, fill fast and produce larger and heavier grains. While later-flowering inferior spikelets, usually located on proximal secondary branches, are either sterile or fill slowly and produce smaller grains. The poor grain-filling of inferior spikelets is more aggravated in the new bred “super” rice cultivars that have numerous spikelets on a panicle. Poor filling of inferior spikelets not only limits the realization of great yield potential, but also degrades rice quality, especially milling and apparent qualities. There are many explanations to the poor filling of inferior spikelets, including carbon limitation, sink capacity limitation, unbalance in hormone levels, low activities and/or expressions of enzymes involved in sucrose-to-starch conversion, and “flow” impediment. Recent studies have shown that low physiological activities of sink (grains) at the initial grain filling and low conversion efficiency from sucrose to starch during the active grain filling period contribute to the poor filling of inferior spikelets. It is observed that the ratio of sugar to spikelets at the heading stage (amount of non-structural carbohydrate in the stems and sheaths over the number of spikelets at heading) significantly correlats with the physiological activities of sink, and the ratio of abscisic acid (ABA) to 1-aminocylopropane -1-carboxylic acid (ACC, a precursor of ethylene) significantly correlats with the grain filling rate, indicating that increases in the ratios of sugar to spikelets and of ABA to ethylene would be two important regulatory approaches to improve the filling of inferior spikelets. Further studies are essential by investigating how environmental factors (including cultivation techniques), factors of the whole plant, and factors within the spikelets regulate the filling of inferior spikelets. A deep understanding of the regulation mechanism that limits the filling of inferior spikelets would lead to efforts that could greatly enhance grain filling and, consequently, increase the yield performance of rice.

 水稻籽粒充实优劣和粒重高低与颖花在穗上着生的部位有密切关系。通常, 着生在稻穗中上部早开花的强势粒, 灌浆快、充实好、粒重高; 着生在稻穗下部迟开花的弱势粒, 灌浆慢、充实差、粒重低。这种强、弱势粒灌浆的差异在大穗型超级稻品种上表现更为突出。弱势粒充实差和粒重低不仅阻碍了水稻产量潜力的发挥, 而且还会降低稻米品质, 尤其是加工品质和外观品质。关于弱势粒灌浆差的机理有许多假设, 包括同化物供应限制、库容限制、激素间不平衡、蔗糖-淀粉代谢途径关键酶活性或基因表达量低、“流”不畅等。最近研究表明, 灌浆始期籽粒库生理活性低和活跃灌浆期蔗糖转化为淀粉的生化效率低是弱势粒灌浆差的重要原因; 增加抽穗期糖花比(抽穗期茎与鞘中非结构性碳水化合物与颖花数之比)及灌浆期脱落酸与乙烯比值可以显著提高籽粒库生理活性和籽粒灌浆速率。从环境(含栽培)、植株整体水平以及籽粒内在因素等不同层次上深入研究水稻弱势粒灌浆差的机理及其调控途径, 对于破解弱势粒灌浆差的科学难题、挖掘水稻生产潜力具有十分重要的意义。

为探明大穗型水稻品种的穗肥适宜施用时期，促进水稻结实率与产量的提高，对2个大穗型品种（Y两优5845和金优785）进行不同时期穗肥调控研究，分析穗肥施用时期对水稻结实率及产量的影响。结果表明：倒三叶施用穗肥后Y两优5845和金优785一次枝梗退化率比倒五叶施穗肥的降低0．64百分点和2．33百分点，二次枝梗降低5．27百分点和1．78百分点，颖花退化率降低7．88百分点和5．84百分点，结实率达85．62％和83．41％；倒三叶施用穗肥的处理产量显著高于倒五叶施肥的处理，Y两优5854和金优785分别达960．3 kg/667m2和873．21 kg/667m2。结论：大穗型水稻品种适宜的穗肥施用时期为倒三叶期，此期施用穗肥能够保证减数分裂期有充足的营养供应，防止枝梗及颖花退化，增加结实率，从而提高产量。

以中迟熟杂交稻品种黔优18为材料,在总施氮量相同的条件下,研究在水稻生长的前后期(基蘖肥与穗肥,穗肥分别在水稻倒5叶叶龄期与倒3叶叶龄期施用)不同比例氮肥施用量,对水稻吸收利用、群体质量、产量的影响.研究结果表明:水稻产量、氮肥农学利用率、干物质积累量均与前后期氮肥施用比例呈抛物线关系,基蘖肥与穗肥所占总氮比例过高过低均不能获得最高产量、氮素利用率、最优群体结构;其中基蘖肥与穗肥比例为5:5、6:4获得高产,产量分别达836.36 kg/667 m2、813.87 kg/667m2;成穗率高,齐穗期至成熟期的干物质积累量最高,氮素的农业利用率也显著高于其他比例,计算出当地百公斤稻谷吸氮量1.85 kg.