Characteristic of Dry-Matter Accumulation and Nitrogen-Uptake of Super-High-Yielding Early Rice in China

Chinese super-high yield rice (Oryza sativa L.) breeding project has developed many new varieties with high yield capacity. But there is a lack of information about the dry matter and N accumulation and translocation promoting grain yield of super-high yield early rice (SER). This study was conducted to compare grain yield, and the association of dry matter and N accumulation and translocation between super-high yield early rice and ordinary early rice (OER). Three SER varieties Lingliangyou268, Jinyou458, and Luliangyou996, and two OER varieties Zhuliangyou09 and Jinyou463 were grown in Yujiang County, Jiangxi Province, China, in 2008 and 2009. Grain yield, yield components, dry matter and N accumulation, and dry matter and N translocation related parameters were measured for each variety. A significant difference in grain yield was observed among the varieties and varietal groups. The SER varieties increased rice yield by 20.2% compared with OER varieties. The higher yield of SER varieties was attributed to larger panicle size, which resulted in large sink size. Differences between SER varieties and OER varieties in translocation-related parameters were found. Dry matter and N accumulation and translocation-related parameters were greater for SER varieties compared to OER varieties. Grain yield was positively and significantly correlated with dry matter and N translocation-related parameters, suggesting that the sink strength could be involved in the translocation-related parameters.