Abstract: 【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.

Key words: hybrid indica rice (Oryza sativa. L) , highland mountain area , accurate fertilizer model (AF) , population quality , yield