Predicting the Geographic Distribution of Seville Root-Knot Nematode Based on the Biomod2 Model

The Seville root-knot nematode, Meloidogyne hispanica (Nematoda: Meloidogynidae), is a highly specialized plant pathogen nematode, posing a significant threat to global agricultural production. Based on 18 validated global occurrence records of M. hispanica, the biomod2 ensemble model was applied to predict its potential habitat distribution under current and future climate scenarios. The global distribution records of M. hispanica were collected and combined with 19 bioclimatic variables and one environmental variable, while five key environmental factors (i.e., bio15, bio7, bio13, bio2, and elevation) were picked out for model development through principal component analysis (PCA) and correlation screening. The results indicated that the biomod2 ensemble model chooses from 13 individual algorithms (ANN, CTA, FDA, GAM, GBM, GLM, MARS, MAXENT, MAXNET, RF, RFd, SRE, and XGBoost), of which seven high-performing models were retained for the TSS-weighted ensemble that balances coverage, stability and explanatory capability, with a cross-validated TSS of 0.724 ± 0.144 and AUC of 0.892 ± 0.059 (calibration TSS = 0.923, AUC = 0.976). The current potential suitable habitats of M. hispanica are primarily concentrated in the low-latitude region between 15° N and 30° N, including the Gulf of Mexico, the Caribbean Islands, the South Asian subcontinent, and the coastal areas of Southeast Asia. Under future climate scenarios, the potential suitable habitat range of M. hispanica in China was projected to expand northward, contract westward, and remain absent from plateau regions. The North China Plain and the southern Loess Plateau would likely become new expansion areas, whereas the southwestern plateau would show a reduction in suitability. Given the limited number of occurrence records, this study should be interpreted as a preliminary, climate-based risk assessment to guide surveillance and quarantine prioritization.