Abstract
In a farm-oriented enhancing aquatic system (FOEAS) paddy field and a conventional heavy-clay paddy field, we investigated the effect of high temperature during the ripening period on the yield and appearance quality of rice. The groundwater level of the FOEAS paddy field during the ripening period was maintained at 10–30 cm below the soil surface, while in the conventional paddy field, surface water was completely drained, remaining 30–50 cm below the soil surface, in late July. The sap bleeding rate of the plants in the FOEAS paddy high-temperature field was significantly higher than that in the conventional high-temperature paddy field. The difference was caused mainly by the increase in water uptake from soil below a depth of 12 cm in the FOEAS paddy field. Panicle temperature in the FOEAS paddy field was significantly lower than that in the conventional paddy field. The incidence of cracked, milky-white, and white-based rice kernels in the FOEAS paddy high-temperature field was significantly lower than that in the conventional high-temperature paddy field. In addition, the yield of rice in the FOEAS paddy field was higher than that in the conventional paddy field due to increases in the ripening rate and the thousand grain weight. The soil penetration resistance value in the FOEAS paddy field was equal to that in the conventional paddy field, confirming that the bearing capacity of the soil is suitable for machine harvest.
The results indicated that FOEAS in heavy-clay large-scale paddy fields is effective for conducting both large-scale mechanical work and maintaining the appearance quality of rice under high air temperature during grain filling.
