Synergies or Trade-Offs Between Rice Yield and Grain Quality? A Meta-Analysis of Paired Field Experiments Mainly in China

Although numerous studies have evaluated the effects of agronomic practices on either rice yield or grain quality, a comprehensive assessment of potential synergies and trade-offs between these traits across multiple management strategies remains limited, which is of great importance to simultaneously improving rice yield and quality in the future. In the present study, a meta-analysis was conducted with paired observations of rice yield and quality when various agronomic practices, including altering sowing date, alternate wetting and drying, growth regulator application, nitrogen application, potassium application, organic fertilizer application, increased planting density, silicon application, variety selection and zinc application, are employed. We found that applications of growth regulator and potassium fertilizer can improve rice yield, milling and appearance quality simultaneously. Enhanced rice yield and milling quality can be achieved through variety selection and organic fertilizer application. Additionally, enhanced rice yield and appearance quality can also be achieved through silicon application. However, though increased planting density and altered sowing date can improve rice yield and milling quality, they cause lower appearance quality. By contrast, though nitrogen application can improve rice yield and milling quality, it comes at the expense of appearance and eating quality. Therefore, our results indicate that there are indeed complex synergistic relationships and trade-offs between rice yield and various aspects of grain quality. Integrated agronomic technique packages should be employed to simultaneously improve rice yield and grain quality in the future.