| Popis: |
To explore the relationship between cultivated land fertility and corn head smut occurrence, 515 main corn growing counties were selected, and the relationship between corn head smut incidence and cultivated land fertility was modeled using classification and regression tree(CART), random forest(RF) and extreme randomized trees(ERT) models, with organic matter(OM), total nitrogen(TN), total phosphorus(TP), total potassium(TK), available phosphorus(AP), available potassium(AK), and PH as characteristic variables. The classification accuracy of the different models were compared. The comprehensive classification performance of RF and ERT was obviously better than that of CART. The three models had higher Precision(Pr), Recall (Re), and F1 score(F1) values on disease grade 1 (GⅠ), and the classification effect was better than that of disease grade 2(G Ⅱ). Considering the importance of accurately monitoring the high incidence of diseases and reducing leakage rates in classification and prediction for disease prevention and control, the ERT model, with its higher Re value on G Ⅱ was finally determined to be the best classifier. Additionally, importance analysis between the variables characteristic of cultivated land fertility and degree of disease occurrence showed that the incidence of corn head smut correlated appreciably with AP, TK, pH, and TP. The results provide clues and support for further mechanistic research into effects of cultivated land fertility factors on corn head smut. |
