| It is so important for food security in China to successful breeding of Super hybrid rice and extensive promotion, but the yield potential of super hybrid rice is difficult to full play in real production, and the yield is not the same in different ecological area. In order to further prove the high-yield mechanism of Super hybrid rice and achieve stable high yield of large area, between 2007 and 2009, we have designed 3 comparative tests in this study, such as cultivation pattern, mulching modes and water managements, researched of high-yielding population characteristics, canopy characteristics and yield formation mechanism of super hybrid rice. The major results were summarized as follows:1 Plastic film mulching dry-land cultivation and irrigation in the middle and late contributed to high yield of Super hybrid rice 88S/1128. Under different cultivation pattern, total spikelet number increased 7.4～16.00%, seed setting rate increased 3.94%-10.08%, and thousand-grain weight improved 0.10g～0.79g in plastic film mulching dry-land cultivation mode. Dry matter accumulation of aerial part and Underground area had obvious advantages in all periods, and its' yield were increased 167.2kg/hm2,843.9kg/hm2 and 1125.9kg/hm2 than plastic film mulching waterland cultivation, nude field dry cultivation and conventional cultivation. Under different water managements, the yield of whole growth period irrigation treatments was the highest in the film and nude field cultivation and whole growth period no-water treatments was the lowest. Effective panicle number, total amount of spikelet and thousand-grain weight of 88S/1128 under plastic mulching, straw mulching and liquid film covering were higher than nude field, and its'yield were increased 16.81%, 9.59% and 3.65%.2 Plastic film mulching dry-land cultivation and irrigation in the middle and late increased coverage index, the average leaf angle and direct radiation penetration coefficient, and improved canopy structure of Super hybrid rice. Plastic film mulching much better than the conventional cultivation in different cultivation pattern, and plastic film mulching waterland cultivation and nude field dry cultivation in between, and their canopy coverage index of very poor up to 0.28. Under different water managements, canopy structure of whole growth period irrigation treatments much better than no-water cultivation, the medium-term and late irrigation in between, and leaf inclination angle of plastic film cultivation was greater than nude field cultivation in different treatment, and full heading time is greater than 20 days after heading, but contrary to effective coverage index. Under dry-land conditions, canopy structure of 3 mulching modes are better than nude field cultivation, plastic film is better than covered with rice straw and liquid membranes.3 Plastic film mulching dry-land cultivation had high photosynthetic rate and transpiration rate, in particular, NET photosynthetic rate of plastic film mulching cultivation were higher 11.84%,19.92% and 14.90% than nude field dry cultivation, plastic film mulching waterland cultivation and conventional cultivation, and its' transpiration rate were higher 12.1%～25.1% than their, and as the growth stages of promoting the difference increased. On the other hand, compare with CK mulching cultivation enhanced fluorescence dynamics parameter-Fv/Fm and Yield, it's beneficial to potential activity of PSⅡand actual capture rate of luminous energy. Among the treatments of mulching film, straw and liquid film, mulching film was the best one. Otherwise, different water manage has little effect on fluorescence dynamics parameter of super hybrid rice.4 Film mulching cultivation could significantly improve canopy microenvironment of Super hybrid rice 88S/1128, lowered canopy temperature, and increased humidity in the canopy. Canopy temperature and humidity monitoring showed that canopy-air temperature difference and crown-air humidity difference had the same trend. The average daily temperature range of plastic film water cultivation was the most, up to 2.07℃, and diurnal variation appeared the first small cooling humidification peaks around 9 o'clock am, canopy-air temperature difference up to 2.27℃and improved 10.93%. It appeared the second cooling humidification peaks at 8 o'clock pm, canopy-air temperature difference was 2.86℃, crown-air humidity up to 20.39%.5. Calcium absorption characteristics of upland rice were different under different water management. The treatment of later stage irrigation enhanced the content of calcium in leaf, middle stage humidification and later stage irrigation favored calcium absorption of stems, later stage humidification was favorable for spic absorpting calcium. On the other hand, tillering stage to heading stage irrigation was not propitious for calcium absorption of stems and leaf. The treatment of heading stage to maturation stage irrigation enhanced calcium content of stems and leaf obviously, but the spic calcium content was reduced. The research showed that, more SiO2 tansfer to stems at full-heading stage under the treatment of mulching and irrigation,so the stems was more strong and had positive significance for insect resistance and lodging. Otherwise, mulching cultivation enhanced the absorption ability to N, P and K, among them, the treatment of plastic film mulching was most obvious.6. Analysis showed that the effects of yield factors on yield from big to small was total grains per panicle, the grain number per spike,1000-grain weight. At full heading stage the second leaf's photosynthetic rate effect the grain number per spike, at milk ripe stage flag leaf's photosynthetic rate effect the 1000-grain weight. Humidity difference and temperature difference between air and canopy were important factor for photosynthetic rate at in late growth stage, among them temperature difference was direct effect, humidity difference was indirect effect. The humidity of canopy increased significantly when second leaf's transpiration rate was improved. At the same time, transpiration promoted dry matter and SiO2 accumulation of spike, calcium transport to stems and leaf, it was dvantageous to high yield.
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