Principles and practices of intelligent fertilizer recommendation based on yield response and agronomic efficiency

Irrational application of chemical fertilizers is common in small scale agricultural production due to the lack of handy fertilizer recommondation method. The Institute of Agricultural Resources and Agricultural Planning of the Chinese Academy of Agricultural Sciences, together with 39 soil-fertilizer research teams across the country, developed a crop fertilizer recommendation system based on yield response and agronomic efficiency that is applicable to small scale farmlands under different agro-ecological conditions and cropping systems in China. The development of the fertilizer recommendation based on the large datasets from fertilizer field trials conducted in China’s main cropping production areas in multiple years, including crop yield response, agronomic efficiency, nutrient uptake and utilization. The QUEFTS (quantitative evaluation of the fertility of tropical soils) model was used to calculate the optimal nutrient uptake, and the correlation between soil indigenous nutrient supply, crop yield response and agronomic efficiency of applied nutrient was calculated, and a fertilizer recommondation model was established in this way. Based on the model, a user-friendly Nutrient Expert (NE) system was developed by means of information and intelligent cloud computing technology to facilitate technology application. Users can have the tailored fertilizer application strategy by only inputing some basic information such as crop yield, fertilizer application history, organic and inorganic fertilizer inputs, and whether straw returning, etc. From the above the soil fertility level, the NE system takes into account the residual nutrients from previous season, crop rotation system, and organic fertilizer application, etc., and proposes a fertilizer application recommendation in line with 4R nutrient management strategy (right source, right rate, right time, and right place), while trade-off the agronomic, economic, and environmental impacts. Multi-site field validation trials have confirmed that the NE system, as a science based and easy to grasp tool, can synergize both fertilizer use efficiency and environmental protection, is an important fertilizer recommendation method to ensure higher crop yield and profitability.