| In order to compare yield formation characteristics under different cultivation patterns, field experiments with early season rice Luliangyou 996 and late season rice Tianyouhuazhan were conducted in Changsha and Liuyang city, China, from 2008 to 2009. The cultivation patterns are designed as:"Sanding" cultivation (A), Seedling broadcasting and no-tillage (B), Traditional cultivation (C), Traditional cultivation and minus fertilizer (D). The field plots with four replications are fixed by using freedom plot arrangement. In each field plot, the tiller number per hill and plant height were recorded once every three days, and the leaf area index (LAI), plant dry matter accumulation and NPK nutrient content were measured at mid-tillering stage, panicle initiation stage, heading stage and maturity stage, and some enzyme activity of flag leaf, root/shoot ratio, oxidation ability of root were determined after heading, and the grain yield and its components are measured at maturity stage. The results were showed as follows:1. Tiller number increased with the advancement of growth at first, and gradually decreased after reaching maximum tiller number until it become stable. Generally, the tiller number of fertilizing treatments (patterns A, B and C) was significantly higher than that Traditional cultivation and minus fertilizer (pattern D). The maximum tillering stage of pattern A and C was 30 days after transplanting, which was 10 days earlier than that of pattern B. Plant height increased with the advancement of growth, and there was no significant different observed in the plant height among the fertilizing treatments. Moreover, the growth of rice plant under pattern C was faster at early stage and slower at late stage.2. The yield of super rice was significantly affected by cultivation patterns. The highest yield was observed in pattern A, which produced 7.21-7.41 t/hm2 and 8.61-9.28 t/hm2 in early and late rice, respectively. For early rice, the average yield of pattern A was 2.81% and 13.95% higher than that of patterns B and C, respectively. For late rice, the average yield of pattern A was 9.34% and 7.50% higher than that of patterns B and C, respectively. However, there was no significant difference between patterns B and C in the yield.3. The yield components were significantly affected by cultivation patterns. The highest panicle number per unit land area was observed in B pattern, which produced 310.29-339.11 panicles/m2 and 279.00-376.04 panicles/m2 in early and late rice, respectively. Compared with pattern A, the panicle number per unit land area of pattern B increased by 7.72-12.20% and 6.50-31.99% in early and late rice, respectively. Compared with pattern C, the average panicle number per unit land area of pattern B increased by 22.37% and 24.83% in early and late rice, respectively. There was a large difference in grain-filling percentage among different cultivation patterns. In Changsha, the highest grain-filling percentage was observed in pattern D, and pattern C taken the second place. Differently, in Yongan, the lowest grain-filling percentage was observed in pattern D. Grains per panicle were difference among different cultivation patterns. Compared with pattern C, the grains per panicle of pattern A increased by 3.53-13.62% and 1.91-8.06% in early and late rice. There was no significant difference in grain weight among different cultivation patterns.4. Root characteristics of super rice were significantly affected by cultivation patterns. The bleeding potential in neck of per spikelet, and oxidation ability of root at full heading stage of pattern A were 9.51-14.05% and 7.05-19.18% higher than those of pattern C in early and late rice, respectively. Moreover, the root/shoot ratio of pattern A were higher than pattern C in early rice by 8.06-25.71% and in late rice by 20.41-21.28%.5. Physiological characteristics were significantly affected by cultivation patterns. LAI increased with the advancement of growth for all of the four cultivation patterns. For early rice, the highest LAI was observed in pattern A (5.07-5.33) at full heading stage. For late rice, the highest LAI was observed in pattern B (5.73-6.91). The SPAD readings in flag leaves decreased initially at 10 days after full heading and decreased sharply at 20 days after full heading in both early and late rice. From 20 days after full heading to maturity, the SPAD reading of pattern C decreased by 39.82% in early rice and 126.27% in late rice, which were the sharpest decline observed among the four cultivation patterns. The highest photosynthesis rate was observed in pattern A (18.82 umolCO2 m-2·s-1) in early rice and in pattern B (20.77 umolCO2 m-2·s-1) in late rice.6. Dry matter accumulation and grain-filling were significantly affected by cultivation patterns. Dry matter accumulation and translocation of pattern A was less and lower in early growth stage. From transplanting to panicle initiation, the matter accumulation of pattern A was 113.74-179.99g/m2 in early rice, and 296.28-437.46g/m2 in late rice, the dry matter translocation was 13.99-15.09% in early rice, and 6.86-14.52% in late rice. However, there was more dry matter accumulated after heading stage in pattern A. The initial grain-filling rate (GRo), maximum grain-filling rate (GRmax) and mean grain-filling rate (MGR) of pattern A were 1.50,2.70,1.74 mg.grain-1.d-1 in early rice, and 1.02,1.78,1.15 mg.grain-1.d-1 in late rice, respectively.7. N, P and K uptake amounts in aboveground plants and agronomic nitrogen use efficiency were significantly effected by cultivation patterns. At early stage, compare with the other patterns, N, P and K uptake amounts in aboveground plants of pattern C was higher, which were 2.43g/m2,0.285 g/m2 and 1.99 g/m2 in early rice, and 5.01 g/m2, 0.727 g/m2 and 5.52 g/m2 in late rice, respectively. However, at maturity, the agronomic nitrogen use efficiency of pattern A was higher than that of pattern C by22.00-84.29% in early rice and by 32.38-71.80% in late rice. Moreover, the agronomic nitrogen use efficiency of early rice was higher than late rice in both 2008 and 2009.High yield of pattern A was mainly attributed to higher grain number per panicle and' harmonious relationship among yield components. There was no significant difference in grain yield between patterns B and C. However, the pattern B could yet be regarded as an efficient cultivation pattern in labor-shortage regions as it has potential benefits including time-saving, labor-saving and energy-saving.
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