Flooding depth and duration concomitantly influence the growth traits and yield of rice*

Abstract

AbstractFood security concerns regarding decreased rice yields due to flooding are growing, especially concerning those due to the frequent occurrence of floods caused by extreme climate events, which pose a severe threat to the growth and yield of rice. While rice planting is widespread and gradually expanding worldwide, the effect of flooding stress on the growth traits and yield of rice has not been fully elucidated. To assess the effect of flooding stress on the growth traits and yield of rice, a pot experiment was conducted with three flooding depths and three flooding durations. The effects of flooding stress at the panicle initiation stage on plant height, leaf area index, photosynthetic rate, transpiration rate, biomass accumulation, and yield components were explored. Following the application of flooding stress, compared to that of the non‐flooding stress application, 1/3‐hr–7‐day, 2/3‐hr–7‐day, and 3/3‐hr–7‐day flooding stress levels led to significant increases in plant height by 10.5%, 11.7%, and 14.8% in 2019 and by 9.9%, 10.3%, and 13.0% in 2020, respectively (p < .05). Compared to the non‐flooding stress treatment, the 1/3‐hr–7‐day, 2/3‐hr–7‐day, and 3/3‐hr–7‐day flooding stress treatments led to 14.98%–21.16%, 35.11%–46.85%, and 81.26%–84.49% decreases in rice yield, respectively. Taken together, the results of this study indicate that flooding stress has a negative influence on the growth traits and yield of rice. Therefore, the variations in growth traits and yield loss should be explored when rice is flooded.