Common population characteristics of direct-seeded hybrid indica rice for high yield

Changchun Guo, Xiaojuan Yuan, Yanfang Wen, Yonggang Yang, Yangming Ma, Fengjun Yan, Bo Li, Zhonglin Wang, Mengwen Xing, Rongping Zhang, Zhiyuan Yang, Jun Ma, Yongjian Sun

Agronomy Journal，Volume115，Issue4，2023（IF=2.65）

https://doi.org/10.1002/agj2.21359

Abstract

Direct seeding of rice has attracted attention because of its simplicity and rapidity compared with traditional cultivation methods. However, the geographical location of the rice region in Southwest China is complex, and the common characteristics of high yield of direct seeding hybrid indica rice and the law of nutrient absorption and accumulation are still unclear. This study results demonstrated that the mean yield of high-yield varieties (HYV) in the two ecological points increased by 17.68%–19.98% and 17.37%–27.06%, respectively, compared with low-yield varieties (LYV). The high tillering ability and effective tillering rate of HYV promoted a large leaf area index (LAI) and a strong photosynthetic capacity and stimulated the accumulation of aboveground biomass and nitrogen, phosphorus, and potassium nutrients in rice plants, which were finally transported and allocated to the grains to maintain high yields. Correlation analysis indicated that yield and its components were closely related to spatial population structure and nutrient accumulation and allocation. In particular, LAI at the full heading stage, net photosynthetic rate, aboveground biomass from jointing to maturity stage, and nitrogen, phosphorus, and potassium accumulation and distribution from jointing to full heading stage have the strongest correlation with yield and its components. Therefore, improving the effective tillering rate and LAI, as well as the accumulation and distribution of aboveground biomass, nitrogen, phosphorus, and potassium of rice plants from jointing to full heading stage, are the common laws for the formation of high yield of direct seeding hybrid rice in different ecological areas.