Abstract: To explore the characteristics of dry matter production and photosynthesis of rice under different planting methods in the rice-wheat cropping system in the lower Yangtze River, with early-maturing late japonica rice, late–maturing medium japonica rice and medium-maturing medium japonica rice (including japonica conventional rice and japonica hybrid rice) as materials, we compared the dry matter accumulation, distribution, translocation and leaf area, photosynthetic potential (PP), crop growth rate(CGR) and net assimilation rate (NAR) of rice by using precisionartificial transplanting with middle and strong seedlings grown in dry nursery (ATR), mechanical transplanting with small seedlings (MTR) and direct seeding (DSR). Results showed that: (1) Rice yield by using different planting methods was significantly positively correlated with totaldry matter accumulation at maturity, dry matter accumulationfrom headingto maturity, and dry matter accumulation from jointing to heading under the premise of ensuring the dry matter accumulation appropriate at heading, but not with dry matter accumulation from sowing to jointing and the harvest index. (2) For dry matter weight of population, there was no significant difference among the three planting methods before jointing, after jointing ATR was the highest, followed by MTR, DSR was the lowest, and the difference was increasing with the growing process. However, the dry matter weight per stem of ATR was the highest, while that of DSR was the lowest in the whole growth period. (3) For dry matter accumulation at different stages, there was no significant difference among the three planting methods from sowing to jointing, but ATR was significantly higher than MTR, MTR was significantly higher than DSR at the stages from jointingto headingand from heading tomaturity. The ratio to total dry matter weight increased in turn for ATR, MTR, DSR from sowing to jointing, there was no many difference among them from jointing to heading, and reduced in turn for them from heading to maturity. (4) For dry matter distribution, the dry matter weight ratio of panicle and stem to total plant at maturity reduced in turn for ATR, MTR, DSR, and that of leaf and sheath increased in turn for them. However,the ratio ofleaf at booting, heading and waxy ripe stages reduced in turn for them. (5) For dry matter export and transformation, the export rate and transformation rate of leaf and stem reduced in turn for ATR, MTR, DSR, and the matter was transportedback in stem after waxy stage, the amount of matter transportedback for ATR was most, while that for DSR was least. The export rate in sheath was no many difference in generally, but the transformation rate for ATR and MTR was lower than that for DSR. (6) For photosynthetic production, before jointing, the leaf area index was generally no many difference for three planting methods, the PPreduced in turn for ATR, MTR, DSR, and the CGR and NAR increased in turn. From jointing to heading, the PP also reduced in turn for ATR, MTR, DSR, but there was no significant difference for CGR and NAR. The leaf area rate of productive tillers at heading had no significant difference among different planting methods, but the leaf area rate from flag leaf to 3rd leaf of ATR was significantly higher than that of MTR, and MTR was significantly higher than that of DSR. After heading, the leaf area index, PP, CGR and NAR of ATR were the highest, while those of DSR were the lowest. The results suggested that dry matter and photosyntheticproduction of rice with different planting methods have their own characteristics. Compared to MTR and DSR, ATR has the advantages that the dry matter accumulation is appropriate in the early stage and significantly higher in the middle and late stage, so the total dry matter accumulation is significantly higher and its distribution is reasonable, the export and transformation rate is high, and the photosynthetic production capacity is great after heading.

Key words: Rice, Planting method, High-yielding cultivation, Characteristics of dry matter production, Characteristics of photosynthetic production