Peanuts are highly vulnerable to aflatoxin contamination. Based on the Balanced Sampling-Random Forest early warning model for aflatoxin contamination in peanut established previously, this study aimed to analyze the main technical parameters and practical application effects of the model through systematic application research, which could provide a critical technical support for risk prediction of aflatoxin in post-harvest peanuts in China.

The model was used to predict the aflatoxin contamination risk of 153 main peanut producing cities in China from 2019 to 2020 by selecting the data of one month before the peanut harvest, including one geographical variable (latitude) and three climatic variables (precipitation, average air pressure, and daily average temperature of 8:00-20:00) as the key input parameters of the model. The immunoaffinity chromatography-high performance liquid chromatography-fluorescence detection method was used to determine the aflatoxin content of 2 164 peanuts to obtain the aflatoxin contamination data areas. The accuracy, precision, sensitivity, and false-positive rate of the model were analyzed to clarify the application effect according to the predicted risk and the actual risk of the model.

A total of 125 areas were predicted as low-risk areas of aflatoxin, of which 116 areas were consistent with the actual measurement results, but 9 high-risk producing areas were misjudged as low-risk areas (False negative). Meanwhile, 28 areas were predicted as high-risk areas of aflatoxin, of which 15 areas were consistent with the actual measurement results, but 13 low-risk producing areas were misjudged as high-risk producing areas (False positive). Therefore, the accuracy of the model was 85.61%, the false-negative rate was 8.49%, and the false-positive rate was 5.88%.

The application of the Balanced Sampling-Random Forest early warning model could predict the risk of aflatoxin contamination in peanuts, which provided the technical support for scientifically guiding the harvesting, storage and utilization in post-harvest peanuts in China, thereby reducing the loss of aflatoxin contamination and guaranteeing the quality and safety of agricultural products.