Abstract: The indica super rice cv. Zhongjiazao17 was used to study the tiller dynamics, dry matter production characteristics, yield component characteristics and the effects of different amount of nitrogen fertilizer and planting density on yield were investigated. The results showed that when the amount of nitrogen fertilizer was applied from 0 to 195 kg·hm^-2 and the planting density was from 24×10⁴ to 30×10⁴ hills·hm^-2, the yield of rice increased with the increasing planting density. The yield was the highest when the amount of nitrogen fertilizer was 105 kg·hm^-2 in high-density planting pattern, and the yield was the highest when the amount of nitrogen fertilizer was 150 kg·hm^-2 in low-density planting pattern. The stem and sheath weight and the whole dry matter weight at heading stage increased under optimal nitrogen fertilizer application and planting density, which was beneficial to maintaining higher leaf SPAD value during late growth stage, delaying leaf senescence and enhancing the dry matter production after heading stage, thus the new assimilation products (direct supply quantity of assimilates) and apparent export percentage of leaf and stem and sheath increased after heading. The nitrogen agronomic efficiency and partial factor productivity could be improved under appropriate nitrogen application amount and planting density．

Key words: nitrogen fertilizer, density, late indica super rice, yield, yield component, material component