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Core Ideas Nutrient Expert is a new nutrient management approach and is confirmed for use in north‐central China.The continual feasibility of Nutrient Expert was evaluated through multiple‐point field experiments.This is the first report of Nutrient Expert on improving environmental benefits of winter wheat. Over application of N and P and poor nutrient management have become a common practice on the North China Plain, and lead to low nutrient use efficiency (NUE) and serious environmental problems. Thus, nutrient management for crops must be improved. In this study, 315 field experiments were conducted from 2011 to 2014 in major winter wheat domains in north‐central China to validate the continual feasibility of the Nutrient Expert (NE) system for improving NUE and reducing greenhouse gas (GHG) emission. The NE system significantly increased grain yield, profitability, and NUE, and decreased GHG emission. Compared with farmers’ practice (FP), the NE treatment reduced N and P inputs by 41.4 and 30.1% (115 kg N ha−1 and 36 kg P2O5 ha−1), respectively, and increased K input by 51.5% (25 kg K2O ha−1). Compared with the FP and soil testing (ST) treatments, the NE treatment increased agronomic efficiency of nitrogen (AEN) by 70.0 and 13.3%, recovery efficiency of nitrogen (REN) by 73.8 and 13.3%, and partial factor productivity of nitrogen (PFPN) by 58.5 and 22.2%, respectively. Compared with the FP and ST treatments, the NE treatment reduced total N2O emissions by 54.8 and 26.3%, total GHG emissions by 44.8 and 22.9%, and GHG emission intensity by 45.8 and 22.0%, respectively. These results confirmed that NE is an effective method to make fertilizer recommendations for wheat in north‐central China and has the potential to improve yield, NUE, and profitability, with low environmental pollution.

Imbalanced fertilization has caused lower yield and nutrient use efficiency for radish ( Raphanus sativus L.) production in China. Estimating nutrient requirements for radish is crucial in optimizing fertilization to resolve the problem. On-farm experiments in the radish-growing regions of China from 2000 to 2017 were collected to investigate the relationship between fleshy root yield and nutrient accumulation in radish plant using the Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model. The QUEFTS model predicted a linear increase in fleshy root yield if nutrients were taken up in balanced amounts until yield reached about 60%–70% of the potential yield. The balanced N, P, and K requirements in radish plant simulated by the QUEFTS model were 2.15, 0.45, and 2.58 kg to produce 1000 kg of fleshy root, and the corresponding internal efficiencies (IEs, kg fleshy root per kg nutrient in total plant dry matter) for N, P, and K were 465.1, 2222.2, and 387.1 kg kg −1 . The simulated balanced N, P, and K removal by fleshy root to produce 1000 kg fleshy root were 1.34, 0.30, and 1.93 kg, respectively. Approximately 62%, 67%, and 75% of N, P, and K in radish plant were presented in the fleshy root and removed from the soil. Field validation experiments confirmed the consistency between the observed and simulated nutrient uptake values. The QUEFTS model was proven to be effective for estimating nutrient requirements of radish and will contribute to develop fertilizer recommendations for radish cultivated in China.

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